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BakingProblemsSolved
RelatedTitles
SteamedBreads:Ingredients,ProcessingandQuality
(ISBN:978-0-08-100715-0)
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BakingProblems
Solved
SecondEdition
StanleyP.Cauvain
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PrefacetotheFirstEditionxxxi
PrefacetotheSecondEditionxxxiii
WoodheadPublishingSeriesinFoodScience,TechnologyandNutritionxxxv
Introductiontoproblemsolvingtechniques
1.1Howtoproblemsolve
1.1.1Low-breadvolume3
1.1.2Keyholing4
1.2Therecord
1.3Theanalysis
1.4Modellingtechniques
1.5Matchingpatternsandvisualisingchanges
1.6Theinformationsources
1.6.1Personal17
1.6.2Written17
1.6.3Constructingknowledgetreesandknowledgefragments23
1.6.4Knowledge(computer)-basedsystems26
1.6.5TheWeb27
1.7Newproductdevelopment
1.7.1Concept28
1.7.2Productdevelopmentinvestigation
prototypeproduct29
1.7.3Scale-uptocommercialisationassessment30
1.7.4Prototypetrialsontheplant30
1.7.5Pre-launchtrials30
1.7.6Launch30
1.7.7On-goingproductmaintenance/handover31
1.8Conclusions
References
Rawmaterials
Wheatandgrains
2.1.1Canyouexplainthefunctionsofthedifferentcompo-
nentsinthewheatgrainand,aftermilling,their
contributionstothemanufactureofbakedproducts?33
2.1.2Weunderstandthatmillersoftenuseamixtureof
differentwheatstomanufacturethefloursthatthey
supplytous.Canyouexplainwhytheydothis?36
wepurchase.Whatcharacteristicsshouldwelookfor
Fats
2.3.1Whatarethecriticalpropertiesoffatsformaking
bread,cakesandpastries?77
2.3.2Canyouexplainthedifferenttermsusedtodescribe
bakeryfats?Whatarethefunctionalitiesofthe
differentformsinbaking?79
2.3.3Ourbreaddoughsprovesatisfactorilybuttheydo
notriseintheoven.Onsomeoccasions,theymay
evencollapseandblistersformonthedoughsurface
inthecornersofthepans.Whatisthecauseofthese
problems?81
2.3.4Whatistheroleoffatinthemanufactureof
puffpastry?83
2.3.5Ourpuffpastryfailstorisesufficientlyeventhough
webelievethatweareusingthecorrectleveloffat.
Areweusingthecorrecttypeoffat?84
2.3.6Whatistheroleoffatincakemaking?85
2.3.7Wearemakingall-buttercakesbutfindthatafter
bakingtheylackvolumeandhaveafirmeating
character.Whyisthisandisthereanywayto
improvethecakequality?86
2.3.8Wehavebeenusingoilintheproductionofour
spongecakesbutwewishtochangetousingbutter.
Canyouadviseonhowtodothis?87
2.3.9Wewishtoproduceasoftereatingspongecakeand
2.5.14Whatislecithinandhowisitusedinbaking?117
2.5.15Wehavebeenhavingsomeproblemswiththe
qualityofourbread,pastriesandbiscuitsandone
solutionthathasbeenrecommendedtousisthat
weshouldaddareducingagenttoourrecipes.Canyou
tellusmoreaboutreducingagents,andhowthey
functioninbakedproducts?118
2.6.1Ihaveheardthatyeastrequiresoxygenbefore
itcanworkcorrectly,isthistrue?121
2.6.2Howdoesbakersyeastproducecarbondioxide
inbreadmaking?122
2.6.3Arethereanyparticularprecautionsthatweshould
takeinhandling,storingandusingbakersyeast
inthecompressedform?123
2.6.4Whatarethecausesofthedarkbrownpatcheswe
2.7.6Whyareemulsifiersusedinbreadimprovers?
AndhowdoIdecidewhichoneIshouldbeusing?141
2.7.7Whatis
-cysteinehydrochloride,andwhatisitused
forinbreadimprovers?142
2.7.8Canweaddareducingagentduringdoughmaking
sothatwecanreducetheenergyinputrequired
duringthemixing?143
2.7.9Whatisdeactivatedyeastandhowisitused?144
isparticularlynoticeablewithourwholemealproducts.
Whatisthecauseofthisproblemandarethereany
remedieswecanapplytopreventitsoccurrence?158
4.1.5Whenviewingthecrumbappearanceofoursliced
bread,wenoticetheappearanceofdarkstreaksand
patcheswhichhaveacoarsercellstructureandfirmer
texturethantherestofthecrumb.Isthisaproblem
withunevenmixing?159
4.1.6Periodically,weobservetheformationoflargeholes
inthecrumbofourpanbreadsandsuspectthatthe
adjustmenttothepressureboardonourfinalmoulder
isfaulty;canyouconfirmoursuspicions?161
4.1.7Wehavebeenhavingproblemswithholesappearing
indifferentplacesinourpanbreads.Canyouexplain
wheretheycomefromandhowtoeliminatethem?
4.1.14Wehavebeenexperiencingsomevariationincrust
colouronourbreadproducts.Whatcausesbread
crustcolourandwhyshoulditvary?179
4.1.15Whyisthesurfaceofsomebreaddoughscut
beforebaking?180
4.1.16Whatarethebestconditionstouseforproving
breaddough?182
4.1.17Canwefreezeourunproveddoughpiecesandstore
themforlateruse?184
4.1.18Whathappenswhendoughbakes?185
Otherfermentedproducts
4.2.1Canyousuggestwhatstepscouldbetakentoprevent
ourrounddoughnutsshrinkingorcollapsingwithin
afewminutesofleavingthefryer?210
4.2.2Thefermenteddoughnutswearemakingtendtobe
quitegreasytoeat.Canyouadviseonhowwecan
reducethisproblem?212
4.2.3Wehaverecentlybeenexperiencingdifficulties
withtheproductionofourbreadrolls.Thefinished
rollshavepoorvolumewithlargeholesinthecrumb.
Canyousuggestmeasureswemighttaketoeliminate
thesefaults?213
4.2.4Wehavebeenreceivingcomplaintsthatoursmall
fermentedproducts,suchasrolls,teacakesandbaps,
arestalingtooquickly.Canyouadviseonhowwe
canimprovetheproductsoftness?214
4.2.5Ourfruitbreadsriseveryslowlyintheproverandfail
toriseanyfurtherintheoven.Wemakesomeunfruited
productswiththesameformulationandtheyare
satisfactoryinallrespects.Canyouexplainwhy?216
4.2.6Ourfruitedbunsfrequentlycollapsewhentheyleave
theoven.Wehavetriedbakingthemforlongerbut
thisdoesnotcuretheproblem.Ourfruitedloaves
madewiththesamedoughdonothavetheproblem.
Canyouadvise?217
4.2.7Wearemakingafruitedbunproductandfromtime
totimeexperienceproblemswiththeproductflowing
outduringproofandbaking.Canyouidentifythe
causeandsuggestaremedy?218
4.2.8Whenwecutopenbreadrollsandhamburgerbuns
whichhavebeenstoredinthedeepfreezefor
aperiodoftimeweobserveawhiteringjustinside
thecrustwhichhasahardeatingcharacter.
Wheredoesthisproblemcomefrom?219
4.2.9Wearenotalargebakerybutareplanningto
part-bakeandfreezebreadproductsforbake-offat
somelatertime;whatpointsshouldwebeawareof?221
4.2.10Whenwereheatpar-bakedproductswefindthatthey
remainsoftforonlyashortperiodoftime,typically
anhourorso,buttheyquicklygohardandbecome
inedible.Ifwedonotreheatthemwefindthat
par-bakedproductscanstayfreshforseveraldays.
Whatcausesthechangeintherateoffirming?Isit
theadditionalmoisturelostonthesecondbake?223
4.2.11Whilereadingaboutthemanufactureofhamburger
buns,weseereferencestothepHandTTAofthebrew.
Whatdothesetermsmean?Whenarethey
usedandwhatisthepurposeofcontrollingthem?224
Cakes,spongesandmuffins
5.16Oursmallcakesoftenshrinkexcessivelyduringcooling.
Howcanweavoidthis?
5.35Wehavebeenmakingarangeofdifferentcakesizesusing
5.47Wehavebeenmakingcakemuffinsandfindthatwhen
wecutthemopen,theyhavelargeverticalholes
inthecrumb.Whyisthisandhowdoweeliminatethem?
5.48Whydosomeofourcakemuffinsleantooneside
duringbaking?
5.49WhatisBaumkuchenandhowisitmade?
Biscuits,cookies,crackersandwafers
6.1Howimportantarethedoughandbattertemperatures
inbiscuit,cookie,crackerandwafermaking?
6.2WhatisVolandwhatisitsfunctioninbiscuitsdoughs?
6.3Abatchofourbiscuitscontainingoatmealhasdevelopeda
soapyafter-tastewhichmakesthemunpalatable.
Whyisthis?
6.4Fromtimetotime,wehavenoticedawhitediscolouration
onthesurfaceofourall-buttershortbread.Canyouexplain
whythisoccurs?
6.5Weproducebiscuits-containingpowderedfructosewhich
wecreamwiththefatandsucrosebeforeaddingtheother
ingredients.Recently,wehaveseentheappearanceofbrown
spotsontheproduct.Doyouknowwhatcausesthiseffect?
thanothers.Canyousuggestanyreasonswhyweshouldbe
7.1.16Wehavebeentryingtofreezefullyprovedcroissant
forlaterbake-off.Canyouidentifytheimportant
criteriafortheirsuccessfulproduction?355
7.1.17Wearemakingpuffpastry,Danishpastriesand
croissantusingallbutterandoftenhaveproblems
withtheprocessingofthepastesandfeelthatwedo
7.2.8Wearehavingproblemswiththecustardtartsthatwe
make.Thepastryshellisverypalecoloured,butifwe
increasethebakingtime,wefindthatthecustardfilling
isnotverystableandshrinksawayfromthecaseduring
storage.Ifweraisethebakingtemperature,thecustard
fillingboilsandbreaksdownduringstorage.Canyou
8.7WestandourfinishedchouxbunsonU-shapedcardboard
andwraptheminacellulose-basedfilm.Recently,wehave
observedthegrowthofmouldcoloniesontheproducts.
Whyisthis?
8.8Oursconesaremadefromfrozendoughbutfrequentlylack
volume.Wealsofindthatthecrumbcolourisratherbrown.
Canyouoffersuggestionstoimproveourproductquality?
8.9Someofoursconeshaveacoarsebreakatthesideandan
opencrumbcellstructurebuttheresultsarenotconsistent.
Canyoupleasesuggeststepswemighttaketoobtain
8.20Afterstoringourcoatedproductsovernight,wefindthat
cracksforminfondantcoating.Canyousuggestwaysto
overcomethisproblem?
8.21Wemakesugarpasteshapesandstoretheminplastic
containersforlateruse.Inafewdays,theshapessoften
andareinclinedtodroop.Canyousuggesthowwemight
overcomethisproblem?
8.22Wewouldliketostoreourheavilyfruitedweddingcakes
aftercoatingwithmarzipanforsometimebeforeweice
thembutfindthatthemarzipanhardens.Whyisthisand
howcanweachieveouraims?
8.38Whyisasmallamountofbicarbonateofsodaadded
8.56Whatarecorn(Maize)tortillas?Andhowaretheymade?
8.57Whatistrencherbreadandhowwasitused?
8.58WhatistheproductknownasaGrantloaf?
Processesandequipment
whichareveryhardeating.Aretheproblemsrelatedtothe
performanceofourfreezer?
9.12WehaveseenreferencestotheMiltonKeynesProcessbut
canfindverylittletechnicalinformationontheprocess
Canyoutellmewhatitis(was)itandhowitis(was)used?
9.13Canyouexplaintheprinciplesofvacuumcoolingofbaked
productsanditspotentialapplications?
11.9Wehaveheardpeoplereferringtosynergyintheuseof
ingredientsinbakingprocesses,whatisthisprocessand
canyouidentifyanyexamples?
11.10Whatarepolyolsandhowaretheyusedinbaking?
11.11Whatisacrylamide?Wheredoesitcomefromandhow
dowelimitit?
11.12Whatisosmoticpressureandwhatisitsrelevance
tobaking?
11.13Whatisresistantstarch?
11.14Whataretheoriginsofthecottageloaf?
Index501
PrefacetotheFirstEdition
Fromtimetotimeweallencounterproblemsinthemanufactureofbaked
Thispageintentionallyleftblank
PrefacetotheSecondEdition
IncombiningBakingProblemsSolvedandMoreBakingProblemsSolved
intoasingleeditionitwasimportanttobearseveralthingsinmind.Onewas
thatwhilebakingtechnologycontinuestoevolvemanybakingproblemscan
stillberelatedtotheunderlyingfundamentalprinciplesofbakingandsoin
onesenseremainessentiallyunchanged.Agoodnumberoftheproblems
andsolutionsdescribedinthiseditionwillbefamiliartoreadersoftheear-
lierworks.Someupdatingoftheinformationgivenwitheachquestionand
answerwillbeinevitablebecauseofchangesinrawmaterials,processesand
Becausebakingisacontinuallyevolvingtechnologynewproblems
requiringnewsolutionsemergeandthereareagoodnumberofexamplesin
thisedition.Technicalknowledgemovesonandsoinanumberofcasesitis
possibletoprovidemorerelevantorcomprehensiveanswerstoknownpro-
blems.Newproblemsoftenemergewhenanyoneofthecomponentsofthe
complexingredient-recipe-processbalanceischanged.Weneverusedto
havetheproblemisacommonstatementthatonehearswhichonlyunder-
liestheneedtohaveagoodgraspofunderlyingprinciples.Newproduct
developmentalsothrowsoutitsownchallenges,especiallywhentraditional
boundariesareover-stepped.Inmanywaysthisisgoodnewsforbaking
becauseitgeneratestheneedformoreresearchtounderstandwhatcontri-
butestoproductqualityandloss.
Noneoftheabovecommentsnegatetheneedforasystematicapproach
toproblemsolvingthoughnewideasarealwaysvalued,hopefullysomeof
theadditionsto
Chapter1
,IntroductiontoProblemSolvingTechniques,fall
andnewinformationwasuppermostinmymind.IhopethatIhave
succeeded.
Finally,Iwouldliketotakethisopportunitytothanktwopeoplefortheir
contributionstothissecondedition.First,thelateLindaYoung,my
co-authoronbothpreviousworks,whosesupportisgreatlymissedbut
whoseinspirationliveson.Secondly,myspecialthanksgotomycolleague
andfriendRosieClarkforhersterlingeffortsinbringingtogetherandrecon-
cilingthecontentsofthetwoprevioustitles;herinputtothissecondedition
hasbeeninvaluable.
S.P.Cauvain
xxxiii
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Emergingtechnologiesforpromotingfoodsecurity:Overcoming
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Innovationandfuturetrendsinfoodmanufacturingandsupply
chaintechnologies
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Integratingthepackagingandproductexperienceinfoodandbev-
erages:Aroad-maptoconsumersatisfaction
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Chapter1
IntroductiontoProblem-
SolvingTechniques
Youcantsolveaproblemwiththesametypeofthinkingthatcausedit.
Einstein
ThequotefromEinsteinmayseemlikeastatementoftheobvious,butafter
manyyearsofexperienceinthebakingindustry,Ihaveseenthattheobvious
isconstantlyoverlookedwhenitcomestotryingtosolveproblemsor
developnewproductsandprocesses.Indeed,thereisrelativelylittlediffer-
youarerequiredtousedifferentthinkingtothatyouwouldnormallyusefor
establishedproductsandprocesses.Inessence,bothscenariosarevindica-
tionsofEinsteinsview.
Problemsthatshowasunexpectedvariationsinbakeryproductquality
dooccurfromtimetotime.Oftenconsiderabletime,effortandmoney
arerequiredtoidentifythecausesandsolutionsconcerned.Unexpected
qualityvariationsarenottheexclusiveprovinceofanyparticularsizeof
manufacturingunit:theycanoccurinbothlargeandsmallbakeries.Norare
theyexclusivetotheproductionbakery:Eventhebest-controlledtestbakery
orlaboratorycanexperienceunexpectedfluctuationsinintermediatesorfinal
productquality.Becausetheoutcomeofabakingoperationdependsoncom-
oftenthecasethatitisonlywhenthefinalproductleavestheoven
intermediateproducts(e.g.,dough,batter,paste)exhibitqualitydefects
whichrequireanimmediatechangetobemade.
Manybakeryoperationsstillhaveartisanorcraft(small-scale)roots.Even
withthearrivalofindustrial-scalebakingmanyyearsago,themanufacturing
principlesstillrelyonunderstandingheuristicrulesandrelativelylimiteddata
analysis.Thelevelofautomationandtheabilitytocollectandanalyse
datafromanindustrialbakerystilllagsalongwaybehindthatofother
1
BakingProblemsSolved.DOI:
http://dx.doi.org/10.1016/B978-0-08-100765-5.00001-1

2017ElsevierLtd.Allrightsreserved.
manufacturingenvironments.Thereissomeroutinedatacollectionand
analysisforproductionandbusinessmanagementpurposes(e.g.,yieldfroma
givensetofrawmaterials),orforlegislativereasons(e.g.,bakinglossesto
determinepoint-of-saleweightorproductmoisturecontent),butthecollection
andintegrationofdataon-linefortheoptimisationofbakeryofbakery
processesandproductsremainsmeagre(
Cauvain,2015
).Thechallengeliesas
muchwithknowingwhattomeasureandwhatdatatocollect,asitdoeswith
theanalysis.Insuchcontexts,theemphasisondeliveringtheappropriate
productqualitywillinevitablyoncombiningamethodicalapproachwith
relevantknowledge.
Thereisnomagictoproblemsolving.Itisnormallyachievedthrough
criticalobservation,structuredthoughtprocessesandaccesstosuitable
odsthatmightbeemployedwhentryingtosolvebakery-relatedproblems.
Indoingso,asnotedabove,wemustrecognisethatbakingisacomplex
mixtureofingredientandprocessinteractions,sothatthesolutionstoour
problemsmaynotalwaysbeinstantinnatureandbecauseingredientsand
processeschange,newsolutionsarealwaysbeingdiscovered.Thecomplex
interactionswhichunderpinbakingdictatethatthereareseldomunique
solutionstoindividualproblems.Inthemajorityofcases,individualquality
defectsareovercomebychanginganumberofingredientandprocess
factorssomeofwhichwillbeapparentlyunrelatedthoughcarefulstudywill
oftenrevealthatrelationshipsdoexistevenwheretheyaremaskedbymore
prominenteffects.
Itwouldalsobeappropriateatthisstagetodealwiththesomewhat
amorphoustermquality.Ultimately,thedecisionofwhatistheright
productqualitylieswiththeconsumer,whatisacceptableorgoodforone
consumermaybeunacceptableorbadforanother.Forthebakerperhaps
thebestbasisfordecidingwhattherightproductqualityisdependson
tobakeryproductionwhichfollow,thereisanimplicitunderstandingthata
particularqualitydefectisdeliveringunacceptable(bad)finalproduct
quality.Inprovidingpotentialsolutionstoparticularproblem,itisrecog-
nisedthatthechoiceofaparticularsolutionwilldependonmanyfactors,
includingcostandpracticalityofapplication.Theanswersgivenshould
beseenasaguideastopossiblesolutionsandsoareoftengivenwitha
degreeofflexibilityastoapplication.
1.1HOWTOPROBLEMSOLVE
perfectlypossibletostumblequicklyontherequiredsolutionbychancebut
moreoftenthannotahaphazardapproachtoproblemsolvingiswastefulof
time,resourcesandmoney.Inaddition,stumblingonthesolutionbychance
2
BakingProblemsSolved
oftenmeansthattherootcauseoftheproblemremainsunidentifiedandthe
opportunityislostforthesystematicassemblyofinformationwhichmay
bevaluableforavoidingorsolvingsimilarproblemsinthefuture.Notall
problemsaresolvedusingexactlythesameapproachbutthecritical
elementsoftheproblem-solvingprocessarelargelycommon.
Inpracticalproblemsolving,wenormallymovefromthe
problem
tothe
cause
andfinallytothe
correctiveaction
.However,wemustrecognise
thatonmanyoccasions,themanifestationofaparticularproblemdoesnot
necessarilyhaveauniqueandidentifiablecauseandsotheremaybeother
problem.Thissituationcanbedescribedschematicallyasfollows:
Problem
-
primarycause
-
contributingfactors
-
correctiveaction
Orinmoresimpletermsas:
Whatisseen
-
why
-
becauseof
-
correctiveaction
Thebasicprocessbecomesapparentifweconsidertwoexamplesof
problemsinbreadmaking;thefirstlow-breadvolumeandthesecond
collapseofthesidesofanopentoppanloaf,oftenreferredtoaskeyholing
(seepage4).
1.1.1Low-breadvolume
Externally,weobservethatthebreadissmallerthanweexpect,andthis
mayalsohaveledtoapalercrustcolourduetothepoorerheattransferto
thedoughsurfaceduringbaking.Internally,thecellstructuremaybemore
openthanusual.
Asbreadvolumeisaconsequenceoftheexpansionofthedoughbycar-
thedoughmatrix(
Cauvain,2015
),therearetwopotentialprimarycausesof
thisproblem

Lackofgasproduction
and
Toseparate
thetwo,wewillneedmoreobservations,andanimportantonewillbe
whethertherateofexpansionofthedoughintheproverandovenwasnor-
malorlowerthanusual.Iftheformerwasthecase,thentheprimarycause
oftheproblemislikelytobelackofgasproductionandpotentialcontribut-
ingfactorsmayincludethefollowing:

yeastactivityorleveltoolow;

lackofyeastsubstrate(food);

doughtemperaturetoolow;

provingtemperaturetoolow;

provingtimetooshort;

saltleveltoohigh;

provingtemperature/time/yeastcombinationincorrect.
IntroductiontoProblem-SolvingTechniques
Chapter|1
3
Ontheotherhand,ifthedoughprovinghadbeenatanormalrateand
therewasalackofovenspring,thenthiswouldleadustorecognisethatthe
sonsfortheproblemincludes:

improverleveltoolow;

incorrectimproverformulation;

combinationofimproverandflourtooweakforthebreadmakingprocess
beingused;

enzymicactivitytoolow;

energyinputduringmixingtoolow;

mixingtimetooshort;

doughtemperaturetoolow.
Notethatthedoughtemperaturetoolowappearsinbothlistsduetoits
effectonyeastactivityandtheeffectivenessofthefunctionalingredientsin
theimproveratagiventemperature,especiallyifascorbicacidandenzyme
additionsareused.
1.1.2Keyholing
Externally,weobservethatthereisalossofbreadshapebutonlyat
thesidesoftheproduct.Internally,wemayseetheformationofdark-
coloured,denseseams,oftenreferredtoascores(see
Fig.1.1
and
Section
4.1.2
).Thecentrecrumbmaybemoreopenthanwenormallyexpectfor
theproductconcerned.
Whyhasthishappened?Clearly,wehavenoproblemwithgasproduc-
tionsincethereisnoevidenceforslowprovingandthebreadhadgoodvol-
thebreadwouldhavelowvolumeasdescribedabove.Inthiscase,theover-
expansionofthecrumbinthecentreoftheloafleadsustotheviewthatin
Thus,theprimarycauseoftheproblemis
arising
fromanumberofpotentialindividualcausesorcombinations.Thecontribut-
ingfactorsmayinclude:

improverleveltoohigh;

incorrectimproverformulation;

combinationofimproverandflourtoostrongforprocess;

enzymicactivitytoohigh;

energyinputduringmixingtoohigh;

mixingtimetoolong.
Fromtheforegoingexamples,wecanseethatobservationandreasoning
arekeyelementsinproblemsolving.Theformercanbereadilysystematised,
4
BakingProblemsSolved
whereasthelatterwillrelyheavilyontheavailabilityofsuitableinformationto
useasthebasisforcomparisons.Thepotentialsourcesofsuchinformation
arediscussedbelow.
FIGURE1.1
Keyholinginbread.
IntroductiontoProblem-SolvingTechniques
Chapter|1
occasionallywemayjumpfrombranchtobranchratherthangoingbackto
thetrunkbeforecontinuingourinvestigation.
Thelengthoftimethatwetaketoidentifythecauseandthecorrective
actionsneededvariesconsiderablyfromoccasiontooccasionandfrom
individualtoindividual,andismorelikelytoberelatedtoouraccumulated
knowledgeandexperiencesratherthanlogicalreasoning.Ourabilitiesto
recogniseandmatchsubtlepatternsareprobablysointuitivethatweare
seldomawareofthem.
1.2THERECORD
Itiscommonforthemanufactureofbakeryproductstobebasedonsome
mayhavebeenintroducedtocompensateforsomeprocesschange.
Forexample,inbreaddoughtheyeastlevelmaybeadjustedtocompen-
sateforachangeinprovertemperaturesothatfinalprovingtimesdo
notvary.

Theprocessingconditions,suchasmixingtimes,energies,ingredients
andbatterordoughtemperatures.Onceagainthevaluesmayfallwithin
acceptablerangesbutcanstillhaveacumulativeeffectwithothersmall

enceorduetovariationsinotherfactors.Forexample,anunavoidably
higherlaminatedpastetemperaturemayresultingreaterdamagetothe
laminatedstructurewhichmayrequireacompensatoryadjustmentto

Processtimings,suchasbakingorcoolingtimes.

Changesinpackagingmaterials.
Therecordmaybesimplifiedbyusingthestandardrecipeasa
proforma
againstwhichtorecordvariations.Suchtechniqueshavebeencommonly
usedtorecordtheweightsofindividualdoughpiecescomingfromthe
divider(see
Fig.1.2
)andcanbereadilyadaptedforanyaspectofbakerypro-
duction.Therecordmaybeonpaper,byinputtosuitablecomputer-based
programsormaybegatheredandstoredautomatically.
Inadditiontotherecipeandprocessrecords,itisveryimportanttohave
aformalrecordoffinishedproductquality.Onceagain,itwillbecommon
tohavesomeformofproductspecificationwithappropriatetolerances
againstwhichtomakeanassessment.Suchtechniquesarecommonlythe
willvary.Manyexamplesofapproachestoqualitycontroltechniquesforthe
bakingindustryareknownandthereaderisreferredelsewhere(e.g.,
1991
;
Manley,2000
).Theroleofqualitycontrolshouldbemorethanthatof
thefinalgatekeeperforproductquality,itshouldprovideanimportantlink
Product
unit weight
(g)
Dough
temperature
(C)
Time to dividerDough
consistency*
S/SS/N/SF/F*
Divider
* Dough consistency codes:
S = softer than normal
SS = slightly softer than norm
al N = normal consistency
SF = slightly firmer than norm
al F = firmer than normal
FIGURE1.2
IntroductiontoProblem-SolvingTechniques
Chapter|1
7
quality.Alltoooften,thequalitycontrolfunctionisdivorcedfromthis
integratedchainofinformationandcommonlyrelegatedtoacheckingrole.
Themanufactureofbakeryproductsissomewhatdifferentfromthatofmak-
ingmanynon-fooditemsinthatisoftenimpossibletoreuseproductwhich
calforefficientandcost-effectiveproduction.Datagatheringisanessential
partoftheinformationchain,integrationoftheinformationiscriticaland
analysisofthedata(seebelow)isvital.
Foruseinproblemsolving,theformalproductspecificationorquality
controlrecordmayrequiresomeadaptationandenlargementassmall,but
commonlyaccepted,variationsmayholdthevitalcluetotheparticularcause
ofaproblem.Inboth,thequalitycontrolandproblem-solvingcontexts
relevantdataonthefinishedproductmayincludethefollowing:

Productsizebasedonheightorvolume.Devicesformeasuringproduct
dimensionsmaybeusedoff-oron-line.Theymaybeassimpleasusing
aruletomeasureloafheightormeasuringproductvolumebyseed
displacementinasuitableapparatus(
Cauvain,2015
)orwithlasersensors
(
Cauvain,2017
).

Shapemaybeassessedsubjectivelyandcomparedwithanaccepted
standard.Theintroductionofimageanalysisoffersopportunitiesfor
recordingproductshape,evenon-line(DipixTechnologiesInc,
www.
dipix.com
).

Theexternalappearanceoftheproductandtherecordingofanyspecial
featuresthatmaybepresentorindeedtheabsenceofexpectedfeatures,
e.g.,lackofovenspringinbread.

Surfaceblemishes,theirsizeandlocationontheproduct.

Thecolourationofallexternalsurfaces.Descriptivetechniques,compari-
sonwithstandardcolourcharts,e.g.,Munsell(Munsell,nodate)or
tristimulusinstruments(
Anderson,1995
)maybeused.Deviationsfrom
thenormshouldbeclearlynoted.

Theappearanceoftheinternalstructure,ifthereisone.Mostbaked
productshavesomeformofinternalstructurethatisanintrinsiccompo-
nentofproductquality.Assessmentofthatinternalstructuremaybe
subjectiveanddescribethesize,numbersanddistributionsofthecells
(openspaces)whichgotomaketheinternalstructure.Cellstructures
maybeunevenlydistributedintheproductcross-sectionorforma
patternthatischaracteristicindifferentproducts.Deviationsfromthe
normmaybenoted.Imageanalysisisnowbeingusedforobjectively
assessinginternalcellstructures(
Cauvain,2013;Cauvain,2017
).

Theinternalcolourmaybeassessedusingtechniquesdescribedabovefor
surfacecolour.Itisworthnotingthatthepresenceofacellularstructure
hasanimpactontheperceptionofcoloursoitisoftencommonpractice
8
BakingProblemsSolved
toincludesomeformofvisualassessment,e.g.,brightness,whichis
differentfromthetruecolourofaproduct.Someobjectiveimageanalysis
systemsofferameasurementofcrumbbrightness,e.g.,C-Cell(
www.
c-cell.info
).

Thephysicalcharacteristicsthatcontributetoeatingqualitymaybe
assessedsubjectivelywith
adhoc
ortrainedpanels.Alternatively,some
formofobjectivetestdesignedtomimicaspectsofsensoryanalysismay
beemployed,e.g.,textureprofileanalysis(
Cauvain,1991
),squeezeand
puncturetests(
CauvainandYoung,2006a;Cauvain,2017
).

Productodourandflavourmaybeassessedsubjectivelyonan
adhoc
basisorwithtrainedpanels.Thedevelopmentoftheso-calledelectronic
sensitivity.
withblankspacesinwhichtoentertheappropriatedataorcomments.
Whereaproductattributecannotbemeasured,anattributescoringsystem
mightbeusedtoprovideamoreobjectivebasisforanalysisoftheproblem.
Anynumberofscoringsystemsmaybeemployed.Oneexampleisgivenin
Fig.1.3
,andothersaregivenintheliterature(e.g.,
Kulp,1991
;
Bent,1997a
;
CauvainandYoung,2006a
).
1.3THEANALYSIS
specificationandinwhatdirection.Theeffectsofanychangescanthenbe
comparedwithexistingknowledgebases(inwhateverform)toprovide
thebasisofadiagnosis.Sadly,fewbakeryproblemsaresolvedwithsucha
simplisticapproach.
Almostallbakeryprocessesincludeanelementofelapsedtime,
e.g.,proving,bakingandlamination,whichmustbetakenintoaccountwhen
analysingthecausesofproblems.Manylargerbakeryoperationsinvolve
continuousproduction,eventhoughtheyarebatchfed,andthisaddsa
furthercomplicationtotakeintoaccountintheanalysis.
Anexamplefrommyownexperienceisthatofaplantmanufacturing
bakedpuffpastryshellswheredeviationsintheproductdimensionswere
identifiedattheendofthebakingprocess.Inthisinstance,theplanthadto
runcontinuouslytobeefficientandnotcompromiseproductquality(i.e.,no
leavingtheovenhadtobeestablishedfirst.Whenthiswasdone,itthen
IntroductiontoProblem-SolvingTechniques
Chapter|1
9
becamepossibletoidentifythecontributionthatanyvariationinthemix
batchcontributedtotheproblem.
Afterestablishingthisrelationship,itbecameclearthatbatch-to-batch
variationwasnottheprimecauseoftheproblemobservedassimpleplotsof
doughpropertiesex-mixer(e.g.,temperatureorrheology)didnotcorrelate
withvariationsinproductqualityevenwhentheelapsedtimeelementhad
beentakenintoaccount.Thesolutiontothisparticularproblemlayinaplot
ofchangesinproductcharacterwithtime(see
Fig.1.4
),whichuponanalysis
showedthatthevariationwasmoreregularthanfirstthought.Atfirstglance,
itappearedtobethewell-knownshiftchangeeffectandtosomeextent
thatwastrue:Notentirelyinthiscaseduetotheoperatoreffectonprocess
addtothevirginpaste.Asthereworkaged,theeffectsonbakedproduct
characterdiminished.Inthiscase,asimpletrendanalysisprovidesthebasis
forthesolutionoftheproblem.
Product .......................................................................................................................
.......
Recipe code ...................................................................................................................
....
Date manufactured ...........................................................................................................
Date evaluated ................................................................................................................
..
Evaluated by ..................................................................................................................
...
Product weight (g) ....................................................................... Notes on key attributes
Product height (mm or max. 10) .................................................................High Low
Volume (cm
3
or max. 10) ............................................................................ High Low
Internal appearance
Crumb cell structure (max. 10) ............................................................... O
pen Close
Crumb uniformity (max. 10) ................................................................... Even Uneven
Crumb colour (max. 5) ..................................................................................................
A
dditional comments ....................................................................................................
..............................................
Total score (max. 100)
................................................................................
Sensory qualities
Aroma (max. 5)
............................................................................................... Off-
odour
Flavour (max. 10)
.........................................................................................Off-f
lavour
Eating qualities (max. 10)
........................................................................
Crumb firmness/softness/crispiness (max. 10)
.......................................
External appearance
Uniformity of shape (10 max.) .......................................................... Collapsed Peaked
Crust colour (5 max.) ............................................................................... Dark Light
Crust break (5 max.) ................................................................................ Even Uneven
FIGURE1.3
10
BakingProblemsSolved
Oneanalysistechniquethathasbeenappliedtocerealscienceand
technologyisrootcauseanalysis(
Stauffer,2000
).Notallbakeryproblems
arelikelytobepotentialsubjectsforthistypeofanalysisasakeyelement
inthistechniqueisthebrainstormingsession.Brainstormingusuallyimplies
thatmorethanonepersonisinvolvedandalltoooftenmanyofusconfront
bakeryproblemsaloneoragainstatimescalethatisinsufficienttogather
togetherthenecessaryteamofexperts.Inmanufacturingprocessesbased
onbatchproduction,stoppingthelineuntiltheproblemissolvedisan
option;however,formanybakeryprocesses,anythingotherthanashort-
termstoppageisseldomanoption.Iftheproblemisapersistentoneorofa
catastrophicnature,thenroot-causeanalysiscanbeasuitabletechniqueto
apply.Theroleofateaminemployingroot-causeanalysisisinvaluable
insolvingintractableproblemsormakingchangestoproductquality.Inthe
lattercase,thetechniquewouldbetotreattherequiredchangeasthoughit
wereaproblem;e.g.,ifIwantgreatervolumeinacake,thenbydiagnosing
thecauseofexcessvolume,Imaywellobtaincluesastohowtoincrease
astopossibleroutestoimprovement.
ThemethodologyknownasSixSigmahasbeenusedtoquantifyhow
bakeryprocessesareperforming.Attheheartoftheoperationistheimple-
mentationofameasurementstrategybasedonnomorethan3.4defectsper
millionopportunities,withaSixSigmaopportunitybeingbasedonthenumber
ofchancesofgettingadefect.Forreasonsalreadydiscussed,theopportunities
forobtainingobjectivemeasurementsinmanybakeriesarelimitedwhich
meansinturn,soarethechancesofusingstatisticalapproacheslikeSix
Sigmaasaroutineproblem-solvingtool.Nevertheless,thedisciplineneeded
toimplementtheSixSigmamethodologyhaspotentialrelevanceforbaking.
TheSixSigmaDMAICapproachisbasedondefine,measure,analyse,
improveandcontrol,allessentialelementsinanymanufacturingprocess.
25
30
35
40
45
50
55
60
024681012
Dough batch number
Pastry height (mm)
Fresh re-work
Stored re-work
FIGURE1.4
Effectofreworkonliftinlaminatedproducts.
IntroductiontoProblem-SolvingTechniques
Chapter|1
11
1.4MODELLINGTECHNIQUES
offoodandnonfoodmanufacturingscenarios,oneexampleisthatofSix
Sigmadiscussedabove.Thedifferenttechniquescanbeusedinproblem
solvingandqualityoptimisation,thoughinthemanufacturingenvironment
simplegraphsasdiscussedintheexampleaboveforalaminatedproduct.
Moresophisticatedstatisticalandmodellingtechniquescanplaytheirpartin
helpingtobuilduptheinformationbaseonwhatthecriticalingredientand
fied,thesecriticalfactorscanbeloggedandmatchedwithproblemswhen
theyoccur.Examplesofmodellingprocessesassociatedwithbakingareoften
associatedwithproductionorfinancialplanning,andenergymanagement
ratherthanproductquality.
Todeveloppredictivemodelswhichdealwithproductquality,itis
commonlynecessarytocarryoutexperimentsinatestbakeryortrialsonthe
plant.Althoughtrialsontheplantarepreferred,theycanbewastefulofraw
materials,energyandtimesothatthemostcommonpracticeistocarryout
evaluationsinthetestbakeryandtranslatetheresultstotheplant.Itis
veryimportanttoestablishanyclearchangesthatarerelevantwhentranslat-
ingtestbakeryresultstoaplantenvironment.Asimpleexampleencountered
bytheauthorwasthedevelopmentofaspongecakerecipeinatestbakery
preparethesamerecipebatter.Inthiscase,itisnecessarytorememberthat
lesscarbondioxidegaswillbelostduringcontinuousmixing(duetothe
thatbakingpowderlevelsshouldbeadjusteddownwardstocompensatefor
thisdifference.Atypicaladjustmentwouldbetoreducethebakingpowder
mixertoachievethesamespongecakevolumeinboththetestbakeryand
ontheplant(
CauvainandCyster,1996
).
Thereareanumberofexamplesofmodellingtechniqueswhichmightbe
appliedtobakeryproducts.
providesareviewofsuitabletech-
niquesthatmaybeappliedtothemodellingofbakedproducts,andthereare
anumberofexamplesinthescientificandtechnicalliterature.Theconcept
behindthedevelopmentofsuchmathematicalmodelsisthatarelatively
limitednumberofexperimentsmaybeusedtobuildmodelsthatcanbeused
topredictchangesinbakeryproductqualityasaconsequenceofchangesin
combinationsofingredientsandprocesses.
Onceapredictivemodelhasbeenestablished,thentheinformationcould
alsobeusedforproblemsolving.Forexample,supposethatweshowby
thelevelofascorbicacidinthedoughandmixingtime.Atsomelaterstage,
12
BakingProblemsSolved
wemayencounteraproblemwithlow-breadvolume,andthenwewouldbe
Chapter|1
canbeusedtohelpseparatesuchnoisefromunderlyingeffects,trendsand
relationships.Inmanymanufacturingprocesses,thespecifiedproductchar-
acteristicscanbeachievedbymanydifferentcombinationsofformulation
aticallyandefficientlyforcombinationsofcontrolfactorsthatminimise
productvariabilityinthefaceofvariationsinnoisefactorssuchasambient
bakeryproducts,inparticularinastudyofthefactorsthataffectthequality
ofpuffpastry(
DTI,1993
).
Insomecases,effectiveproblemso
lvingcanbeinitiatedbystudying
theeffectsofsmallperturbationsonth
eplant.Amajorissuewithcarrying
outtrialsontheplantisthepotentia
llossofproductionarisingfrom
themanufactureofout-of-specificationproducts.However,thereisa
distinctadvantagetoplanttrialsinth
atlargenumbersofsamplesarebeing
madewhichincreasesthepotentialforstatisticalandpracticalanalysis.
Mostproductspecificationshaveadegreeoftoleranceassociatedwiththe
finalproductsothatsmallvariatio
nscanbeaccommodatedwithoutlossof
production.
Thevalueofstatisticsinidentify
theeffectsofingredientorprocesschangesisnotdoubted.However,as
discussedintheexampleabovewhere
acidlevelandmixingtimewasconside
red,therearerelativelyfewsimple
relationshipinbaking.Oneoftenhearsthecommentwithregardtoexperi-
mentsinbakingthatwewillchangeonethingatatime.Sadly,thisissel-
domifever,trueforbaking.Supposethatwanttoconsidertheeffect
ofreducingthebasedoughtemperatureinthemanufactureofcroissant
andwethereforemaketwodoughs,oneat20

Candtheotherat15

C,
thatsimplechangeintemperaturewillaffectgasproductionbythe
yeast,theactivityofascorbicac
idandenzymeifadded,andmost
importantlytherheologicalpropertiesofthedoughduringprocessing.
productqualitybutduetotherangeof
interactions,therelevanceofthe
differenceswithrespecttoproductio
nrequirementsisnotclearandsocare
mustbetakenwhenimplementingact
ionsormodelsbasedexclusivelyon
statisticalsignificancealone.
1.5MATCHINGPATTERNSANDVISUALISINGCHANGES
Sometimeswhendealingwithcomplexproblems,itisanadvantageto
salientinformationonaboard(likeastoryboardforthecreationofafilm).
Asimpleexampleisillustratedin
Fig.1.4
inwhichthepotentialroutes
forthemigrationofmoistureincompositebakeryproductsareidentified
annotatedwithrelevantdataonmoisturecontentsandproductmasses.
14
BakingProblemsSolved
Thedrawingofdiagramssuchasthatshownin
Fig.1.5
helpstoensurethat
calculationsandinvestigations.
Humanbeingshaveasignificantcapabilityforbeingabletomatch
patternsindata,andinmanyways,whenweareproblemssolvingwespend
alotoftimecomparingwhatweseewiththepatternswhichweallholdin
ourminds.Subconsciously,welookforapatternofinformationinacurrent
problemandcomparethatwithpreviouspatternsofeventsandinformation
toseeiftheyprovidecluesforsolvingthecurrentqualityproblem.There
aremanydifferentwaysofcreatingpatterns.Thecreationofknowledge
treesandknowledgefragmentsisoneexampleandisdiscussedinmore
similartothatcreatedbyengineerstoshowthemovementofrawmaterials
throughitsvariousstagesenroutetobecomingafinishedproduct.Thesame
basicprincipleisusedbysystemsanalystswhentheyareconstructingdia-
gramstoshowtheflowofinformationwithdifferentsymbolsrepresenting
differenttypesofactivityordecisionswhichneedtobemade.
CauvainandYoung(2006a)
illustratedpossibleexamplesofpattern
matchingforthebakingindustryusingaseriesofspiderdiagramstorelate
certaincharacteristicsofwheatwiththatofthesubsequentflour,doughand
bread.Aswellasprovidingarelativelysimplemeansofdevelopingpatterns
relatingrawmaterialsandfinishedproductstheprocessofdecidingwhich
characteristicstoincludeinthevariousdiagramsisanimportantfirststepin
understandingthecauseofqualityproblems.
Whenitcomestoidentifyingthekeyrolesofdifferentingredientsand
Aw = 0.6, Moisture = 3%
Mass = 4% of product
Topping
Aw = 0.93, Moisture = 40%
Mass = 10% of product
Filling
Aw = 0.85, Moisture = 25%
Mass = 43% of product
Top cake
Aw = 0.85, Moisture = 25%
Mass = 43% of product
Bottom cake
FIGURE1.5
Schematicidentifyingthecharacteristicsofthedifferentcomponentsofacom-
positecakeproductandthepotentialroutesofmoisturemigration.
IntroductiontoProblem-SolvingTechniques
Chapter|1
15
usefultobeabletoidentifytherelativeimportanceoftheindividualchanges.
Itmaybepossiblethroughmathematicalmodellingtoidentifytherelative
importanceoftheeffectdifferentingredients,recipesandprocessorprocess
changes,butitcansometimesbesufficientinproblemsolvingtouseasimple
diagramtounderstandthedifferentcontributions(
CauvainandYoung,
2006a
).Anexampleofthistypeofapproachisgivenin
Fig.1.6
which
examinestheimpactofsomeprocessandingredientfactorsonthehardness
doughisnotusuallyconsideredtobedesirable,andifthisshouldhappen,
e.g.,throughover-mixing,theresultantproductwillbehardereating.Asthe
sugarlevelinacookieformulationincreases,theresultantproductgradually
losesitsinitialcrumblinessandbecomeharder(e.g.,asseenwithgingernuts)
whileincreasingadditionsoffatgiveincreasinglycrumblinessasthefat
interfereswiththedevelopmentoftheglutenstructure.Theangleatwhich
theindividualvectorsproceedfromtheoriginin
Fig.1.6
givesanindication
oftherelativeimpactofanychangessothatthisrelativelysimplediagram
canprovideafirstindicationofthepotentialinteractionsthattakingplacein
aparticularbakingenvironment.Forexample,from
Fig.1.6
,ifwewishedto
reducethefatlevelinacookieformulationbutdonotwishtoendupwith
aharderbiscuitthenwewouldconsiderareductioninglutendevelopment
byadjustingmixingconditionsormethodsorchangingingredients,suchas
flourtype,whichcontributetoglutenformation.
1.6THEINFORMATIONSOURCES
Notmanyoftheproblemsthatwemayencounterinthemanufactureof
bakeryproductsarelikelytobesounusualthattheyhavenotbeenencoun-
teredandrecordedbefore.Evenwhereanapparentlynewproblemarises,
accesstosuitableinformationsourcesoftenrevealsaproblemandsolution
sosimilarthatitcanbereadilyadaptedtoourparticularneeds.Forexample,
Harder
Crumblie
r
Flour protein
Gluten development
Sugar
Fat
FIGURE1.6
Theimpactofsomeprocessandingredientfactorsonthehardnessandcrumbli-
nessofcookies.
16
BakingProblemsSolved
mostoftheproblemsthatwearelikelytoencounterintheproduction
ofcakeswithheat-treatedcakeflours(see
Section2.2.17
)willhavesimilar
solutionstothosethatwouldapplyifwewereusingchlorinatedcakeflours
(see
Section2.2.17
).Eventhoughitmaybethefirsttimethatwehaveused
aheat-treatedflour,wethereforehaveasuitablebaseforidentifyingthe
solutiontoourproblem.
Theavailabilityofsuitableinformationisafundamentaltoolforour
abilitytoproblemsolvesuccessfully.Traditionally,suchinformationsources
couldbeclassifiedaspersonalandwritten.Morerecently,computer-based
othercasesinformsthatwouldnotbeclassifiedasanelectronicequivalent
ofthewrittenword.
1.6.1Personal
Evenintodaysfast-movingelectronicage,thereisnosubstituteforpersonal
experiencewhichbuildsonesownportableinformationsource.However,
fewofuswillspendlongenoughinpositionsthatallowthesystematic
buildupoftheappropriateknowledgethroughtrialanderrorstudies.
Aspectsofproblemsolvingmaybetaughtinouryearsofacademicstudy,
informationbaserequired.
Personalcontactswithexpertsandconsultantscanbeusedtosupplement
ourindividualinformationbase.Contactswithotherprofessionalbakersand
professionalbakingorganisationsareinvaluablebecauseitallowsaccesstoa
widerrangeofexperiences.Thus,membershipofprofessionalbodiessuch
indevelopingonesownknowledgebase.Attendanceatsuitableconferences,
information.
1.6.2Written
Thescientificandtechnicalliteratureprovidesthemostobvioussource
forwrittenmaterialwhichaidsinprob
lemsolving.Startingacollectionof
usefularticlesandsomeformofin
dexisveryhelpfulinestablishing
yourowninformationbase.Included
inthewrittenformarepictorial
librariesoffaultsandassociatedte
xtrelatedtotheir
identifiedcauses.
Suchlibrariesmaybebuiltforoneselformaybepurchasedfroma
suitablesource.
Overtheyears,manyoftherulesrelatedtoproblemsolvinginbaking
havebeensummarisedandpublished(e.g.,
;
Bent,1997b
;
CauvainandYoung,2006b
).Thesegenerallytaketheformoflistsoffaults
IntroductiontoProblem-SolvingTechniques
Chapter|1
17
andassociatedcauses.Inmanyways,suchrulesareoflimitedvaluebecause
theyseldomconsiderorassignalikelihoodvalueandsoapersonaldegree
ofjudgementastowhichofthecausestoinvestigatefirstisrequired.Such
liststendtodealonlywiththemorecommonproblemsandseldomconsider
causesoffaultsaregivenequalweighting;thus,thereisnoexpressionasto
whetheraparticularcauseismorelikelythananother.
Thevaluesofapersonalrecordcanbesignificantlyincreasedbysystem-
isingtheknowledgerecord.Aseriesofchecklistscanbeconstructedto
identifycontributionsofingredientsandprocessestofinalproductsandtheir
appropriateintermediates(e.g.,dough,batter,paste).Anexampleofsuchan
approachisillustratedforpastryin
Tables1.1

1.6
.Checklistsmaybepopu-
latedwiththetypeofinformationidentifiedin
Chapter3,KeyRelationships
.
Afirstlevelchecklist(
Table1.1
)identifiestheingredientsthatmay
beusedinthemanufactureofpastryandconsidersthepotentialimpactof
theironthevariousfinalproductcharacteristics.Fillinginthisfirstchecklist
TABLE1.1
ExampleofLevel1ChecklistforRecordingthePotentialEffects
ofIngredientsandTheirQualitiesonPasteandPastryCharacteristics
(Level1Checklist

Pastry/IngredientQualities)
PasteConsistency
PasteExtensibility
PasteElasticity
Height/Lift
Shape
Colour
SurfaceAppearance
Mouthfeel
Aroma
Moisture
Firmness/Tenderness
Flourprotein
content
XXXXXX
Flourwater
absorption
XXX
FattypeXXXXX
Fatmelting
point
XXXXX
Sugarparticle
size
XX
ReworkXXXXX
Milk
Egg
18
BakingProblemsSolved
TABLE1.2
ExampleofLevel1ChecklistforRecordingthePotential
EffectsofIngredientLevelsofPasteandPastryCharacteristics(Level1
Pastry/Formulation(IngredientLevel))
PasteConsistency
PasteExtensibility
PasteElasticity
Height/Lift
Shape
Colour
SurfaceAppearance
Mouthfeel
Moisture
Firmness/Tenderness
FatXXXXX
SugarXXXXX
Addedwater
XXXXXX
MilkXXXXXXXXX
EggXXXXXXXXX
ReworkXXXXX
TABLE1.3
ExampleofaLevel1ChecklistforRecordingthePotential
EffectsofProcessingConditionsonPasteandPastryCharacteristics
(Level1Checklist
Pastry/Processing)
PasteConsistency
PasteExtensibility
PasteElasticity
Height
Shape
CrustColour
SurfaceAppearance
Mouthfeel
Moisture
Firmness/Tenderness
MixingXXXXXX
RestingXXXX
Chapter|1
TABLE1.4
ExampleofaLevel2ChecklistforRecordingthePotentialEffectsofIngredientQualitiesonPasteandPastryCharacteristics
(Level2Checklist
Past/IngredientQualities)
Paste
Paste
Paste
Elasticity
Tenderness
Stiff
Less
Less
Less
TABLE1.5
ExampleofLevel2ChecklistforRecordingthePotentialEffectsofIngredientLevelsofPasteandPastryCharacteristics[Level2
Pastry/Formulation(IngredientLevel)]
Paste
Paste
Paste
Elasticity
Tenderness
Stiff
Less
Less
Less
TABLE1.6
ExampleofaLevel2ChecklistforRecordingthePotentialEffectsofProcessingConditionsonPasteandPastryCharacteristics
(Level2Checklist
Pastry/Processing)
Paste
Paste
Paste
Elasticity
Tenderness
Stiff
Less
Less
Less
aneffectornot;thosethatdohaveaneffectcouldbemarkedwithanX.
In
Table1.1
,thedifferentqualityoftheflour,fatandsugarareknownto
haveaneffectandsoaremarkedforconsideration.Reworkhasbeen
includedasaningredientduetotheprofoundeffectthatithasonboththe
pasteandthefinalproduct;thereworkqualitywouldbecontrolledbyits
age,temperatureandlengthofstoragetime(asnotedabove).
willimpactonpastecharacteristicsandfinalproductquality.Theexample
illustratedin
Table1.2
doesnotincludeflourasitiscommonpractice
toassesstheimpactofingredientswithrespecttoflouratastandard
levelinthebakery(
CauvainandYoung,2006a
).Atthisstage,thereisno
needtoconsiderthedirectionofimpact.Thefinallevel1checklistconsiders
theimpactoftheprocessingstepsappliedinthemanufactureofthebakery
productconcerned.In
Fig.1.3
,someexamplesrelatedtothemixing,
processingandbakingofpastesareincluded.Again,itisonlynecessaryto
Thelevel1checklistshelpfocusthesubsequentlineofreasoningwhich
mightbeappliedinproblemsolvingorproductdevelopment.Thesecond
levelchecklistconsiderstheimpactofthelevelofthedifferentrecipe
thedirectionofchangeforgivenproductcharacteristics(e.g.,larger,smaller)
andlinkthesewithchangesiningredientlevel(e.g.,higher,lower)orprocess
conditions(e.g.,mixingtimelongerorshorter).Examplesoflevel2checklists
areillustratedin
Tables1.4

1.6,
andtheyshowthetypeandrangeofinfor-
mationwhichmightbeincluded.Ifaningredientorprocessparameterwas
identifiedatlevel1thenitiscarriedthroughtolevel2.Entriesatlevel2can
bedirectional(asillustrated)orifharddataexist(e.g.,frommathematical
modelling)thesecanbeenteredinsteadtogivethelevel2checklistsamore
predictivecapability.
Missingfromthechecklistapproachistheabilitytodirectlyrecordcomplex
interactions,buttheycanbeausefulfirststepinassemblingthecomplex
knowledgerequiredforsolvingbakeryproblems.Theycanalsobeusefulfor
gatheringandsystemisingtheinformationrequiredforthedevelopmentof
computer-basedknowledgesystems(see
Section1.6.3
).
1.6.3Constructingknowledgetreesandknowledgefragments
Anotherapproachtorecordingtechnicalinformationinvisualformcan
betheconstructionofknowledgetreesandfragments.Usuallytheconstruc-
tionofthetreestartsatthetopandworksdownwardstotheroots.
Inpractice,theinformationthatitholdscanbeusedfromthebottom-up
forproductdevelopmentandfromthetop-downforproductandprocess
qualityoptimisation.
IntroductiontoProblem-SolvingTechniques
Chapter|1
23
Theconstructionoftheknowledgetree
startswiththeidentification
ofafinalproductorintermediatepro
pertyofinterestandproceedsby
identifyingallthosefactorswhichcont
ributetotheidentifiedpropertyor
characteristic,bothindividuallyan
dcollectively.Anexampleofthis
approachisgivenin
Fig.1.7
forliftinlaminatedpuffpastry.Movingfrom
thetopofthetreedownward,wecanseethattheapproachistoprogres-
sivelybreakdowncomplexinteractions
untilsinglecontributingfactorsare
identified;thesemaybeconsideredas
therootsofthetree,evenifnotall
ofthemareplantedintheground.
CauvainandYoung(2006a)
provide
anotherexampleofaknowledgetreefortheeatingqualityofbreadand
cakeproducts.Ascomplexasthesed
iagramsappear,theyonlypartially
addresstheissuesofthecomplexingredient

recipe-processinteractions
whichunderpinbaking.
Sometimes,itisnotpossibletodevelopafullknowledgetree,andit
iseasiertobreakthestructuredownintoaseriesofknowledgefragments.
Thisisatechniquewhichwehavepioneeredandusedinmanysituations.
Anexampleofaknowledgefragmentisillustratedin
Fig.1.8
andisone
relevanttoascorbicacidoxidationinbreadsmadeusingtheChorleywood
BreadProcess.Thefragmentidentifiesanumberofthekeyinteractions
whichtakeplaceinmixingandhowtheyrelatetothequalitiesofthefinal
product.
Knowledgefragmentsarevisualaidswhichhelpyoutoquicklysee
informationandknowledgeaboutaningredient,atermusedinbakingor
aprocessingsteporaboutanyinformationyoumaywishtostructureso
thatitiseasytouseagain,eitherasanaide-memoireortohelpinyour
Pastry lift
Re-work
Process
conditions
Production
e.g. English
Number of fat
layers
Integrity of
the layers
Rest periods
Temperature
profile
Fat
Mixing time
(energy)
Quality
(SFI)
Ratio
to
dough
Base dough
temperature
Flour quality
Temperature
Age
Level
FIGURE1.7
Partofaknowledgetreeidentifyingthefactorsthatcontributetopastrylift.
24
BakingProblemsSolved
understandingofatopic.Theyareconstructedinasimilarwaytoaflow
FIGURE1.8
Exampleofaknowledgefragmentrelatedtoascorbicacidoxidationinthe
ChorleywoodBreadProcess.
IntroductiontoProblem-SolvingTechniques
Chapter|1
Theycanhelpyoutolinkallthetechnicalinformationthatyouacquire
aboutbaking.Intheexampleprovided,oxidationintheChorleywoodBread
Process(CBP),muchoftherelevantknowledgeaboutoxidationisillus-
trated.Themechanismbywhichascorbicacidtakespartinoxidation,the
linkstomixingandenergyrequirements,andpossibleprocessingissuesare
resultofunder-orover-oxidationfortheproductbeingconsidered,inthis
casegenericplantbread,canbeinserted.Byreferencingsomeofthekey
examinedwhenaproductexhibitsaparticularfaulte.g.,coarsestructure.
Anyfragmentsshowingthisfaultcanbeusedinthetrailtofindthecauseof
thefaultanditscorrection.Suchknowledgefragmentscanhaveconsiderable
ortwoaspectsofalargerandmorecomplexstructure.
1.6.4Knowledge(computer)-basedsystems
Computingtechnologyoffersaspecialopportunitytohelpwithproblem
solving,qualityoptimisationandproductdevelopment.Inparticular,reason-
basedprogrammes,commonlyknownasexpertsystems,thesehavebeen
previouslyusedinfaultdiagnosisandlinkedwithcorrectiveaction.The
FlourMillingandBakingResearchAssociationatChorleywoodwasthepio-
neerinapplyingsuchtechnologytothebakingindustrywithworkbeing
continuedintheCampdenandChorleywoodFoodResearchAssociation
(
CauvainandYoung,2006b;Cauvain,2015
).
Expertorknowledge-basedsystemsastheyarenowcommonlyreferredto
cancombinefactsandrulestosolveproblems.Therulescantakeseveral
formsincludingmathematicalmodels,rulesofthumbandintuitiverules.
ThelattermaywelltaketheformofifIincreasethelevelofingredientX
thenpropertyYintheproductwillchangeinapositivedirection(cf.the
checklistapproachdiscussedabove).Suchrulesmaynotquantifythedegree
ofchange,onlythedirection.
Knowledge-basedsystemscancontainmanyruleswhichshouldbe
capableofvalidation.Theyshouldnotcontainopinionbutratherconcentrate
onfacts.Suchsystemscanperformafaultdiagnosiswithinafewminutes
andarecapableofconsideringlargeinformationbasesveryquickly.They
canconsidermanyinteractionsandareoftenwrittentoprovidedegreesof
likelihoodintheanswerssothattheprocessofidentifyingcorrectiveactions
andassigningprioritiesismorereadilypossible.Imagesandtextcanbeinte-
gratedanddisplayedtoprovidepictorialdisplayofproductcharacteristics.
Insomecases,itmaybepossibletodiagnosefaultswithaknowledge-based
systembasedsolelyonimagesrunusingtouch-screencomputingtechnology
(
Young,1998a
).
26
BakingProblemsSolved
considerallthenecessaryinformation.However,theyarenotperfect
becausetheyrelyonhumanprogrammingandsoareonlyasgoodasthe
informationtheycontain.Nevertheless,theycanplayanimportantrolein
aidingproblemsolving,qualityoptimisationandproductdevelopment
(throughwhatif?questioning)andofferasignificantadvantageoverthe
classicalwrittenfaultdiagnosistextlists.
Knowledge-basedsystemshavebeenappliedforproblemsolvingin
theproductionofbread(
Young,1998a
),cake(
)andbiscuits.Inadditiontotheirapplicationforproblemsolving,
theymaybeusedinproductdevelopment(
Young,1997
),processoptimisation,
e.g.,retarding(
YoungandCauvain,1994;Young,1998b
)andfortraining
(
Young,1998a
).
1.6.5TheWeb
ThedevelopmentoftheWorldWideWebandsocialmediahasincreased
therangeofoptionsavailableforinformationandcontactstohelpwith
problemsolving.Therearemanysitesthatcanbeaccessedforproviding
informationonproblemsinbakingbutitisimportanttotrytoensurethat
theinformationreceivedhassomevalidityandcredibility.Itistherefore
besttodealwithreputableandwell-knownsources.
Developmentsinweb-basedtechnologieswillconsiderablyincreasethe
availabilityofcomputer-basedtoolssuchasknowledge-basedsystems.Work
hasbeenundertakentoprovideaccesstosuchprogramsonanon-linebasis,
linkedwiththetransferofappropriatebakingtechnology(
Young,1999
),but
andalliedindustries.
Anumberofprofessionalbodiesassociatedwithbakingoffertheir
problem-solvingservicesviaweb-basedsystems,andtherearealsocommer-
cialorganisationswhoofferassistancewithproblemsolving,commonlyona
websites.
1.7NEWPRODUCTDEVELOPMENT
Muchoftheinformationandadvicethathasbeengivensofarinthis
chapterisrelatedtoproblemsolving.However,therearesignificantsimilar-
newbakeryproducts.Forexample,itisacommonpracticebeforeundertak-
inganewdevelopmenttoconsiderthepropertiesthataresoughtinthe
newproductandcomparethemwithexistingproductqualities.Ifthequality
theyarequalitydefects,thentheinformationandtechniqueswhichare
IntroductiontoProblem-SolvingTechniques
Chapter|1
27
commonlyusedinproblemsolvingarenowequallyapplicabletonew
productdevelopment.Inthisprocess,thequestionisnotHowdoIsolve
thisproblem?ratheritisHowdoImovetheproductqualityinagiven
direction?Knowledgefragmentsandknowledgetreescanhavesignificant
rolestoplayinnewproductdevelopmentbecausetheywillcontainthe
informationwhichallowstheproductdevelopertomakeinformeddecisions
astowhichingredient,recipeorprocesschangestomaketomanipulate
productqualityandshouldalsocontainsomeidentificationofthekey
productinteractions.
Whennewproductsaredeveloped,thetechniquesdescribedabove
shouldassistinmovingthequalityoftheconceptproductunderdevelop-
Formulation
Engineeringrequirements/equipment
Anylegislationissues
Nutritionalissues
In-housecapability
Preliminaryproductcostings/commercialviabilityofproduct
Consumeracceptance
Go/nogodecisionpoint
1.7.2Productdevelopmentinvestigation
prototypeproduct
Go/nogodecisionpoint
IntroductiontoProblem-SolvingTechniques
Chapter|1
1.7.3Scale-uptocommercialisationassessment
Go/nogodecisionpoint
1.7.5Pre-launchtrials
Specificationandprocurementofingredients
Purchaseofequipmentifrequired
Go/nogodecisionpoint
1.7.6Launch

Handovertoproductionteamasaportfolioproduct

1.7.7On-goingproductmaintenance/handover

Confirmationofproductspecificationdefinitione.g.,archiveofrecipe

Qualitycontrolspecificationsandreports

Schedulingconsiderations

Consumeracceptance

Crisismanagementplanforpotentialdisaster/mishapse.g.,changeof
ingredient,changeinlegislation,plantbreakdowns


Keepingtrials
1.8CONCLUSIONS
Manyofuswillbefacedwiththeneedtosolveproblemsassociatedwith
it.Somewillbeminorandsomeextensiveinnature,buttheywillallbe
important.Toalargeextentidentificationofthecauseoftheproblemwill
bebasedonsoundobservationandtheapplicationofappropriateknowledge
inasystematicmanner.Asbakers,wehavetodealwithamixtureofcomplex
ingredientsandtheirmanyinteractionswithoneanotherandtheproduction
processesweuse.Forpracticalbakersmanyofthecausesofproblemsare
hidden,forexample,achangeinflourpropertiesisseldomobviousuntil
adefectiveproductleavestheoven.
Thereisalwaysaneedtofindthequicksolution,andtraditionally,this
formerandareseldomgiventhetimetoobtainthelatter.Moderninformation
technologiescangosomeconsiderablewayinprovidingsuitableproblem-
solvingtoolsforthemodernbaker.However,thereisnosingleuniquesource
thatcanprovideallofthenecessarysolutionstobakingproblemsbutkeen
alwayshelpidentifycauseandsolution.
References
March.
Bent,A.J.,1997a.Confectionerytestbaking.In:Bent,A.J.(Ed.),TheTechnologyof
Cakemaking,sixthed.BlackieAcademic&Professional,London,UK,pp.358

385.
Bent,A.J.,1997b.Cakemakingprocesses.In:Bent,A.J.(Ed.),TheTechnologyofCakemaking,
sixthed.BlackieAcademicProfessional,London,UK,pp.251

274.
Cauvain,S.P.,1991.Evaluatingthetextureofbakedproducts.SouthAfr.J.FoodSci.Nutri.
3(November),81

86.
IntroductiontoProblem-SolvingTechniques
Chapter|1
31
Cauvain,S.P.,2003.Insidethecellstructuresofbakeryproducts.WorldFoodIngredientsFeb,
24,26,28.
Cauvain,S.P.,2013.Measuringcellstructuretounderstandbreadquality.Redaktion

33.
Cauvain,S.P.,2015.TechnologyofBreadmaking,thirded.SpringerInternationalPublishing
AG,Switzerland.
andApplication,seconded.Destech,Lancaster,PA.
Cauvain,S.P.,Cyster,J.A.,1996.Spongecaketechnology.CCFRAReviewNo.2.CCFRA,
ChippingCampden,UK.
Cauvain,S.P.,Young,L.S.,2006a.BakedProducts:Science,TechnologyandPractice.
BlackwellPublishing,Oxford,UK.
Cauvain,S.P.,Young,L.S.,2006b.)
TheChorleywoodBreadProcess
.WoodheadPublishing
Ltd,Cambridge,UK.
DTI,1993.QualityOptimisationintheFoodIndustry

BakingIndustry,DTIProjectCSA1923.DTI,London,UK.
Kulp,K.,1991.Breadsandyeast-leavenedbakeryfood.In:Lorenz,K.J.,Kulp,K.(Eds.),
HandbookofCerealScienceandTechnology.MarcelDekker,NewYork,pp.639

682.
Manley,D.,2000.
TechnologyofBiscuits,CrackersandCookies
,,thirded.Woodhead
PublishingLtd,Cambridge,UK.
ProceedingsofExpertSystems95,the15thAnnualConferenceoftheBritishComputer

168.
Stauffer,J.E.,2000.Rootcauseanalysis.CerealFoodsWorld45,320

321.
ure.BlackieAcademic&P
rofessional,London,UK.
Whitworth,M.,Cauvain,S.P.,Cliffe,D.,2005.Measurementofbreadcellstructurebyimage
analysis.In:Cauvain,S.P.,Salmon,S.E.,Young,L.S.(Eds.),
UsingCerealScienceand
TechnologyfortheBenefitofConsumers
.WoodheadPublishingLtd,Cambridge,UK.
Young,L.S.,1997.Wateractivityinflourconfectioneryproductdevelopment.In:Bent,A.J.
(Ed.),TheTechnologyofCakemaking,sixthed.BlackieAcademic&Professional,London,
UK,pp.386

397.
Young,L.S.,1998a.Bakingbycomputer

passingontheknowledge.In:Proceedingsofthe
45thTechnologyConferenceoftheBiscuit,Cake,ChocolateandConfectioneryAlliance.
London,pp.63

67.
Young,L.S.,1998b.Applicationofknowledge-basedsystems.In:Cauvain,S.P.,Young,L.S.(Eds.),
TechnologyofBreadmaking.BlackieAcademic&Professional,London,UK,pp.180

196.
Young,L.S.,1999.Educationandtrainingforthefuture.In:Proceedingsofthe86thConference

16.
Young,L.S.,Cauvain,S.P.,1994.Advisingthebaker.In:ProceedingsofExpertSystems94,the
Systems.December,pp.21

33.
Young,L.S.,Davies,P.R.,Cauvain,S.P.,1998.Cakes

andinnovationsinexpertsystemsVI.In:Mackintosh,A.(Ed.),Proceedingsofthe18th
Cambridge,December,SGESPublications,Cambridge,UK,pp.42

55.
32
BakingProblemsSolved
Chapter2
RawMaterials
2.1WHEATANDGRAINS
2.1.1Canyouexplainthefunctionsofthedifferent
componentsinthewheatgrainand,aftermilling,their
contributionstothemanufactureofbakedproducts?
Shapesvaryamongthevariouscerealgrainsthoughtheirmaincomponents
aresurprisinglysimilarinmajorconstituentsthoughnottheirratios.Inthe
preparationofwheatflour,wearedealingwiththeseedoftheplantformed
duringitsgrowingcycle.Theindividualseedgrainsarethenextgeneration
ofplantsandcontainallthenutrientsandspecialistcomponentstostartthe
growingcycleunderappropriateconditions.
Theindividualseedgrainsarecompos
edofaseriesofdifferenttissues,
eachwithitsownspecialfunctioninthelifecycleoftheplant.Inbroad
terms,wedescribewheatasbeingco
mposedofaseriesofouterlayers
variouslyreferredtoastheseedcoatorbranskins,aninnerendosperm
andtheembryo.Unfortunately,there
isconfusionintheuseofthelatter
term,andincommonusage,itisoftenreferredtoasthegermofthegrain.
Thetermgermismostcommonlyusedwithinamillingcontextand
referstoanembryo-richfractiono
fthegrainobtainedduringmilling
processes.
Fortheseed,thefunctionsofthedifferentcomponentsisrelatively
clear;thebranlayersencloseandprotectthefoodreserves(theendosperm)
forthegrowthofthefutureplant,whereasitisfromtheembryothat
theprotorootsandshootswillspringwhenconditionsareappropriate.
Thephysicalstructuresandchemicalcompositionoftheseedsarefartoo
complextodescribeinabookonbaking,sothereaderisreferredelsewhere
Theoverallproportionsofthethreemainwheatseedcomponentsvary
grown,butthevariationsarerelativelysmall.Toaddtotheconfusionthat
commonlysurroundsthedifferentcomponentsofwheatgrains,thedefinitions
33
BakingProblemsSolved.DOI:
http://dx.doi.org/10.1016/B978-0-08-100765-5.00002-3

2017ElsevierLtd.Allrightsreserved.
ofbran,endospermandembryoarefuzzy,butinbroadterms,thegrains
(onadrymatterbasis)arecomposedof15%bran,83%endospermand2%
embryo.Themoisturecontentofgrainswillvarydependingonenvironmental
factors;figuresof12
20%inthefieldarenotuncommon,whereasinthe
mill12
15%aremorelikely.
Inwholegrain,anapproximateanalysis(%drymatter)wouldbe:
Sugars2.5
Starch71.5
Pentosans(solubleproteins)3.5
Protein15.0
Lipids(fats)2.5
Cellulose3.0
Minerals2.0
Thedistributionofthedifferentcomponentsthroughoutthegrainisnot
uniformwiththecelluloseandminerals,morelikelytobefoundassociated
withthebranandgermandmostofthestarchintheendosperm.Thus,in
thedifferentmillingprocessesemployedtomanufacturewhiteflours,
thereisaconcentrationofsomeofthegraincomponentsintothedifferent
millingfractions.
Inthemanufactureofbreadandfermentedproducts,itistheproteins
whichareofgreatestconcernastheyhavetheabilitytoformagluten
Celluloseismostoftenlinkedwiththebrancontentoftheflourwhich
tendstohaveanegativeeffectonflourproperties,especiallydoughgas
Sections2.2.1and2.2.2
)butmakesapositivecontributionto
Thenaturallyoccurringsugarsinwheatgrainsisnotusuallyconsidered
tobeimportant,butitisworthnotingthatinthemanufactureofbreadand
fermentedproducts,theydocontributetosupportingyeastfermentation.The
mineralsandvitaminspresentinwheatgrainscontributetothenutritional
valueofflours.
Thelipidspresentinwheatflouraremostlyassociatedwiththegermand
toalesserextentthebran.Theirroleinbakinghasnotyetbeenclearly
defined,inpartbecausetostudythem,itisfirstnecessarytoextractthem
fromwheatflour,andthismayleadtoamodificationoftheirfunctionality
whichisnotrepresentativeofhowtheywouldworkintheoriginalflour.
Furtherreading
Cauvain,S.P.,2015.TechnologyofBreadmaking,thirded.SpringerPublishingInternational,
Switzerland.
Cornell,H.,2012.Thechemistryandbiochemistryofwheat.In:Cauvain,S.P.(Ed.),BreadMaking:
ImprovingQuality,seconded.WoodheadPublishingLtd,Cambridge,UK,pp.35

76.
Lorenz,K.J.,Kulp,K.,1991.HandbookofCerealScienceandTechnology.MarcelDekkerInc,
NewYork,NY.
RawMaterials
Chapter|2
35
2.1.2Weunderstandthatmillersoftenuseamixtureof
differentwheatstomanufacturethefloursthattheysupplytous.
Canyouexplainwhytheydothis?
theyclassified?
dough.Glutenstrengthisarelativenebuloustermwhichreferstoboth
theproteincontentoftheflouraswellastherheologicalpropertiesofthe
mixeddough.Referencesarethereforecommonlymadetostrong,medium
andweakflours,withthemaindifferentiationbeingmadeonprotein
content.Forexample,astrongflourmayhave12%ormoreprotein(onthe
basisofa14%moisturecontent),medium10

12%andweaklessthan
10%.However,withinsuchcategoriesvariationsofprotein(gluten)quality
maybeexpected(see
Section2.2.5
).
onthebakeryproductareainwhichitmaybeused;thus,wheatsmaybe
classifiedassuitableforbreadmaking,cakecookiesandgeneralpurposes.
Thisisnotreallyausefulclassificationbecausetheparticularflourproper-
tiesrequiredforanybakerypurposearenotuniversalandwillbetailoredto
individualrequirements.
Wheatagronomicsarecomplexandfarmerswillbeseekingwheatscapable
veryspecialrequirementsfromwheat;diseaseresistanceandyield,
andthesetworequirementsareuppermostinthemindsofcompanieswho
breedandcommercialis
differentend-uses.
Withthenewadvancesinbreedingscienceandtechnology,newwheat
takesmanyyearsofdevelopmentbeforeitreachesthefarmer.Typically,the
periodis8

12years,andduringthattime,thepotentialqualityattributes
arebeingcontinuallyassessed.Intheearlystagesofdevelopment,therange
ofevaluationtestsislimited,butwithsuccessivetrialyears,thequantityof
extensive.
natureofthewheatplant.Togrowanewcroponanannualbasis,itis
beingusedforsubsequentplanting.Withsuccessivecyclesofplantingand
resistancetodiseasesdiminishes.Theremayalsobechangesinyieldand
alossoffunctionalitywhichaddstothedesirabilityofintroducingnew
RawMaterials
Chapter|2
37
wheatingeneral,differentgeographicalregionshaveevolvedstandardised
protocolsorclassifyingwheatsgrowninthoseregions.Therearemany
someoftheexamplesgivenintheFurtherreadingsection.

UK

Australia
http://wheatquality.com.au/classification/

Canada
https://www.grainscanda.gc.ca/wheat-ble/classes/classes-eng.htm

USA
www.uswheat/org
.
buyerinformation
.
buyersguide
38
BakingProblemsSolved
2.1.4Wehaveheardseveralexperiencedbakerstalkingabout
thenewharvesteffectandtheproblemsthatitcancause.Can
youexplainwhatisbehindthisphenomenaandhowwecan
mitigateitseffects?
Thenewharvesteffectisoneofthegreatmysteriesofthecerealsworld.It
hasbeenmuchdiscussedinthecerealsindustrybutalotoftheevidencefor
itsexistenceisapocryphal.Therehavebeenanumberofscientificinvestiga-
tionsrelatedtothetopic,generallywithinconclusiveresults.Itissaidtobe
responsibleforanumberofdifferent,usuallyunexpected,andoccasionally
catastrophicbreadqualitylosseswhichoccuraroundtheperiodwhenwheat
isnewlyharvested;thesehaveincludedlossofbreadvolumeandcellstruc-
ture,butmostcommonly,doughprocessingproblemsarethemainissues
thatareidentifiedbybakers.
Thebasisforanyeffectisnotclearbuthasvariouslybeenattributedtothe
ripenessofthewheatatharvesting,theshort-termageofthewheatbeforeitis
incorporatedintothemillinggristandeventheshort-termageoftheflourbefore
transitionfrom100%oldcropto100%newcrop;usually,theywillgradually
increasetheproportionofthenewharvestwheatinthegrist.Inmanypartsof
theworld,theglobaltradingofwheatfurthercomplicatesthetransitionas
millersmaybeincorporatingdifferentnewcropwheatsatdifferentmomentsin
time.Itistruethatwheatqualitydoesvarywithdifferentcropyears,butmillers
usuallytakethisintoaccountthroughsuitablequalitytestingandadjustthe
mixedgristofwheatsthattheyuseaccordingly(see
Section2.1.2
).
Millingandbakingprocesseshavechangedconsiderablyinthelast40years,
anditmaybethatsomeofthepastexperiencesthatareretoldbybakersareno
longerrelevant.Thosebreadmakingprocesseswhichrelyexclusivelyonthe
qualityoftheglutennetworkinthedougharelikelytobethemostsensitiveto
theanychangesinflourpropertieswithharvestingyear.Inbreadmaking
processeswhereimproversanddoughconditionersareadded,thentheeffects
ofsmallvariationsinflourqualityarelesslikelytobenoticeable.Itisinterest-
ingtonotethatimproversuppliersareknowntomakesmallchangestothe
formulationofthebreadimproversaroundthenewharvestperiod.
Thenewharvesteffectisnotusuallyassociatedwithminorchanges
ratherwithmoresignificantandunexpectedqualitylosses.Acommon
featureofthesecatastrophicfailuresisthattheyoftendisappearwithout
apparentreasonafterashortperiodoftimeusingthenewflourhaselapsed.
Onepossibleexplanationisthatinlargerbakeries,theprocessconditions
smallchangesinwheatqualitywhichinevitablyoccurfromcropyearto
cropyear.Afteraperiodoftrialanderror,theproblemusuallydissipates
astheplantisreoptimisedtothenewprimaryrawmaterialquality.Weare
sorrythatwecannotgiveyouamoreexplicitexplanation.
RawMaterials
Chapter|2
39
2.1.5Weareabakeryworkingwithalocalfarmerandmiller
toproducearangeoflocalbreadsandwanttousesome
producing.Canyouadviseusonanyspecialissuesthatwe
shouldbeawareof?
Addinggrainsindifferentformstobreadsisagoodwayofintroducinga
Wheat,barleyandryecanbeusedtomakemaltedgrainsandturnedintoa
needtobecarefulofisthatthegrainproductsarenothardanddrywhenyou
makethemastheycanpotentiallycauseunpleasanteatingqualitiesiftheyare
largeparticles.Twoformsofgrainsarecommonlyused;crushedorflaked
andkibbled.Theformerwillbepreparedwithahighermoisturecontentto
aidpreparationandsowillbesusceptibletomouldgrowth.Steamingiscom-
monlyusedtopreparegrainsforflaking.Kibblingyieldsmuchsmallerpieces
ofbrokengrainwhichisveryusefulasasurfacedecoration.
Akeyfactorforyoutoconsideristhatthemaltingprocessinitiatesa
significantlevelofenzymeactivityinthegrains,andtheseenzymeswill
remainactiveinthedough.Theamylaseactivitymaycauseproblemswith
doughsofteningandcontributetoside-wallcollapseinthebakedproduct
(see
Section4.1.2
)orevenkeyholinginseverecases(
Fig.1.1
).Ifyoudo
havethisproblem,thenyoumaywanttoreducetheadditionsofother
enzymeactivematerials,suchasmaltflour,orusealessenzyme-rich
improverifyouareusingano-timedoughprocess.
Therewillbeotherenzymicactivitytowatchoutfor,mostnotably
proteolyticactivitywhichcontributestodoughsofteningandaweakeningof
Themaltingprocessgeneratescomplexsugars,andthesewillalsobe
carriedintothedoughwiththemaltedgrains.Theseshouldnotbea
problem,butifyounoticethattheproductcrustcolourbecomesdarker,
youmaywanttoreformulatetoreduceit.
Youmayneedtoincreasetheproteincontentoftheflourthatyouare
using,asthedoughsystemwillneedtocarrythenon-functionalmalted
grains.
Furtherreading
Pyler,R.E.,Thomas,D.A.,1991.Maltedcereals:productionanduse.In:Lorenz,K.J.,Kulp,K.(Eds.),
HandbookofCerealScienceandTechnology.MarcelDekker,Inc,NewYork,NY,
pp.815

832.
40
BakingProblemsSolved
2.1.6Canwemixoatsoroatproductswithourwheatfloursto
makebakeryproducts?Ifso,arethereanyspecialissuesthatwe
shouldbeawareof?
Oats,incommon,withmanyothergrainsarecomposedofouterbranlayers,
anembryo(germ)andstarchyendosperm;thelatter,incontrastwith
manyothergrainscontainssignificantamountsofproteinandisrichinoil.
Thefirststageinoatmillingistoremovethehuskorouterhulltoyield
cleangroats.Oatmillingfollowsasimilarpatterntowheatmillingbutis
lesscomplex.Thegroatsmaybecut,flaked,milledorgroundtoyieldoat
Thehighlevelofoilinoats(typically5

9%)isdistributedrelatively
uniformlythroughtheoatcomponentswhicharealsorichinlipase.Unless
thelipaseisinactivatedbyheat,oatproductsareveryquicklyproneto
rancidity.Theprocessofinactivatingthelipaseenzymeisknownas
stabilisationandcomprisesheatingtheoatswithsteamandheatforupto2h
atover100

C.Thestabilisationprocessalsocontributestothedevelopmentof
anuttyaromaandflavourinoatproducts.
Cutoatsareusuallymilledtooatmealofdifferentsizegrades,anditis
theseproductswhicharemostcommonlyusedinbaking.Perhaps,thebest
knownbakeryproductswhichuseoatmealarebiscuitsandcookies,oatsmay
beincludedontheirownoralongwithfruitsandnuts.Oatmealbiscuitshave
astrongregionalbiasassociatedwithScotland,andtheyareadenseandfria-
blebiscuitwithadistinctiveflavour.Thereareotherregionalproductswhich
useoatmealsuchasStaffordshireOatcakes(see
Section8.43
).
Theconsumptionofoatbranhasbeenlinkedwiththepotentialfor
loweringbloodcholesterolinthehumandigestivesystem,andthishasledto
itsinclusioninanumberoffoodanddrinkproducts.Theactiveingredient
inthiscontextisthesolublefibregum,
-glucan.
Oatflakesmayfindusealongwithotherflakedgrainsinthemanufacture
ofbreadandrolls,eitheraspartofthedoughorasasurfacedressingto
providetexture.
Oatbranandoatmealareincludedinsomebreadswherethedistinctive
aromaandflavourareseenasbeneficial.Theoatproductsareusuallyadded
toastrongwhiteflourbaseasoatsdonothavethepotentialtocontributeto
breadproductstohaveaslightlydrymouthfeel,butwhencombinedwitha
suitablefilling,e.g.,prawnmayonnaise,theymakeapopularsandwichtype
intheUnitedKingdom.Oatbranisalsoakeycomponentofsomespeciality
cakemuffins.
Furtherreading
Welch,R.W.,McConnell,J.M.,2001.Oats.In:Dendy,D.A.V.,Dobraszczyk,B.J.(Eds.),
CerealsandCerealProducts.AspenPublisher,Inc.,Gaithersburg,MA,pp.367

391.
RawMaterials
Chapter|2
41
2.1.7Whatismicronisedwheat?
Themicronisingprocessinvolvesthetreatmentofgrainbyinfraredirradia-
tionandisnottobeconfusedwithultra-finegrindingbytheMicronizer
2.2FLOURS
2.2.1Canyouexplainwhattheashcontentmeansandshould
Theashtestisbasedontheincinerationofaknownweightofafloursample
at900

Cinasuitablefurnace;thematerialwhichremainsafterincineration
comprisestheinorganicmineralsandisreferredtoastheash(
ICC,2005
).
temperatureofonly600

C(
AACC,2008
applied,theaimremainsthesame.
Themineralsincerealgrainsareconcentratedinthebranlayerswhich
surroundtheinnerendosperm.Thus,asageneralprinciplethehighertheash
contentofawhiteflour,thegreatertheproportionofbranwhichcan
physicalpropertiesofthematerialsconcernedmeansthatthebranskins
cannotbepealedfromtheendosperm-likelayersonanonion,andevenin
themostefficientofflourmills,itisinevitablethatsomefragmentsofthe
branlayerswillfindtheirwayintothewhiteflourwhichessentiallycomes
fromtheendosperm.Theashtestmaythereforebeseenasanindicator
ofthepurityofwhiteflour;inthat,themoreofthebranwhichisincorpo-
ratedwiththewheatendosperm,thehighertheashlevelwillbe.Itfollows
thataswholemealfloursare100%ofthegrain,theashcontentwillbe
considerablyhigherthanthatofwhiteflours.
IntheUnitedKingdom(andelsewhere),thereisastatutoryrequirement
235mgand390mg/100g(
BreadandFlourRegulations,1999
)beforethe
flourleavesthemill.Thisrequirementisrelatedtothenutritionalstatusof
flour.Calciumcarbonateisaninorganicsubstancewhichremainsapart
oftheashresidueontesting.However,unlikebran,ithasnotechnological
impactinbaking.Ascalciumcarbonatewouldmeasureasashusingthetest,
UnitedKingdomflourswillyieldahighervalueanddistorttheapplication
oftheinformationforbakerypurposes.
Inthelightoftheabovescenario,UKmillersdonotroutinelyusethe
ashtesttomonitorfinalflourquality,insteadtheyuseatestcommonly
referredtoasthegradecolourfigure(see
Section2.2.2
).Thistest,carried
outwithaColourgraderwithaspecifiedlightsource(Cauvain,2009),is
basedontheassumptionthathigherlevelsofbranwillyieldadarkerflour
figure(GCF)(seeexamplein
Fig.2.1
),butonevaluecannotbeusedtopre-
dicttheotherwithanydegreeofcertainty.Thisisbecausethedistributionof
mineralsisnotuniformthroughoutthewheatbranlayers,andtheparticle
sizeofthebranalsodistortstherelationship.
RawMaterials
Chapter|2
43
Althoughneithertestcanbeusedtop
redicttheresultsoftheother,
bothhaverelevancetothebreadmakingpotentialofagivenwhiteflour.In
itssimplestform,thehighertheashvalueorGCF,thepoorerthegas
dmaking.This,inturn,meansthat
loafvolumewillfalliftheashorGCFincreases.
Cauvain(2016)
provides
relevantashdataforarangeofmillfractionsincludedinanexampleofa
straightrunwhiteflour.
Inbroadterms,theashlevelhasbeenequatedwiththeextractionrateof
flours(i.e.,theproportionoftheoriginalgrainturnedintoflour).
Kentand
Evers(1994)
publisheddatarelatingmillingextractionratetoashvaluesand
showedthatanincreaseinextractionratefrom70%to85%increasedthe
measuredashlevelintheflourfrom0.44%to0.92%.However,ashlevels
shouldnotbetakenasanabsoluteindicatorofextractionratebecauseas
notedabove,themineralsinthewheatgrainarenotuniformlydistributedin
thegraincomponentsandmillingtechniquescanskewthedata.
References
andApplications,seconded.DEStechPublishing,Lancaster,PA.
ICC

Kent,N.L.,Evers,A.D.,1994.TechnologyofCereals,fourthed.ElsevierScienceLtd.,
Oxford,UK.
TheBreadandFlourRegulations,(1999).SI1999,No.1136

SI1998,No.141,HMSO,
London,UK.
0
0.2
0.4
0.6
0.8
1
1.2
1.4
202468101214
Grade colour figure
Ash (%)
FIGURE2.1
44
BakingProblemsSolved
2.2.2Whatdoesthetermgradecolourfiguremeaninflour
specifications?Howisitmeasured?Whataretheimplications
forbreadquality?
ameasureofflourcolour.Thetechniqueuseslightreflectanceataspecific
wavelengthfromaflour

waterpasteheldinaglasscell.Itwasdeveloped
by
Kent-JonesandMartin(1950)
andrefinedby
Kent-Jonesetal.(1950)
.
TheColourGraderhasundergoneanumberchangestoimproveitsreli-
theevaluationofmillperformance
andflourquality.Althoughgenerally
acceptedasameasureofthelevelofbranpresentinwhiteflours,
itisappreciatedthatGCFisaffe
ctedbyanumberofotherfactors,
includingtheintrinsiccolourofthewheatendosperm(
Barnes,1986
)and
theimpactofanybleachingprocesseswhichmaybecarriedout(the
practiceofbleachingwhiteflours
isbecominglesscommoninmodern
mills).
IntheUnitedKingdom,themandatoryadditionofchalktowhiteflour
meansthatthemeasurementofashasapredictorofthebreadmaking
potentialoftheflourwasmisleadingbecausethemeasuredashvaluewas
raisedbytheadditionofthechalk(see
Section2.2.1
).Thus,GCFcameto
beusedmorereadilyasanindicatorofthelevelofbrancontaminationin
whiteflour.Theformofwheatgrains,especiallythecrease,meansthatitis
anditisinevitablethatsmallparticlesofbranpowderfindtheirwayinto
whiteflour.Thebranparticleshavethesamesizeastheendospermfrag-
mentsandsocannotreadilybeseparatedbysieving.Thelevelofbranparti-
clesmaybereducedthroughaspiration(inpurifiers)astheyarelessdense
Ingeneral,thehighertheGCFvalue,thehigherthelevelofbranpresent
andthedarkerthebreadcrumbcolour.Thisstatementdoesnotconveythe
whitemachinefloursobtainingduringwheatmilling.Thelevelofbranvar-
iesineachofthesefloursaccordingtothelayoutandoperationofthemill.
Cauvain(2017)
providedexamplesofthevariationinGCFamongstmachine
flourswithrelevantbreadvolumedata.
(seeexamplein
Fig.2.1
),butGCFcannotbeaccuratelyusedtopredictflour
ashandviceversa.ItshouldbenotedthatwhentheGCFtestwasdeveloped,
itwasintendedtobeusedwithwhitefloursandsomeasurementsonbrown
orwholemealhavelimitedrelevance.
RawMaterials
Chapter|2
45
Machineflourswhicharehighinbrancontent(i.e.,highashorhigh
GCF)mayoftenbereferredtoaslowgradeflourstoindicatetheirrela-
tivelypoorbreadmakingpotential.Thequantityofsuchfloursproducedand
presentinstraightrunflourisusuallyrelativelysmall,sotheoverallimpact
onflourGCFandloafvolumearisingfromtheiradditionislimited.Flours
whichareespeciallylowinbran(i.e.,lowGCFandlowash)mayoften
bereferredtoaspatentortoppatentflour.Suchflourshavegood
breadmakingpotentialeventhoughtheirproteincontentmaybelowerthana
straightrunflour.
ofwholemealflours;notleastbecausethereliabilityofthemeasurements
canbeaffectedbythesizeonthebranparticleswhicharepresentinthe
flour.Inwhiteflours,thebranparticleswillbenobiggerthanthelargestof
thewheatendospermfragmentswhicharepresent.
References
Barnes,P.J.,1986.Theinfluenceofwheatendospermonflourcolourgrade.J.CerealSci.4,143

155.
andApplications,seconded.DEStechPublishing,Lancaster,PA.
asaffectedbygrade,bymeasurementsofreflectivepower.Analyst75,127

133.
Kent-Jones,D.W.,Amos,A.J.,Martin,W.,1950.Experimentsinthephoto-electricrecordingof
flourgradebymeasurementsofreflectivepower.Analyst75,133

142.
46
BakingProblemsSolved
2.2.3Wehavethewaterabsorptioncapacityofourflour
assessedregularlybutfindthatthisisdifferenttotheactual
waterlevelthatweuseinthebakery.Whatarethereasonsfor
thisdifferenceandisitimportantforbreadmaking?
Thelevelofwaterthatyouaddtoflourforbreadmakingdependsonmany
Chapter|2
Othercontributionscomefromvariationsenzymicactivityandthelevel
ofpentosans(solublecarbohydrates),buttheseareusuallyrelativelysmall
bycomparisonwiththeeffectsofthemainflourcomponents.
Theoptimumconsistencyforabreaddoughishardtodefinebecause
muchdependsonhowthedoughwillbeprocessed.Handprocessingallows
forsensitivehandlingofthedoughwithreadyadjustmentofthepressures
whichwillbeappliedduringmouldingandshaping.Whendoughismechan-
icallyprocessed,theprocessingequipmentcannotadjustitspressures,so
thereisamuchgreaterneedfortheconsistencyofthedoughtobeoptimised
andtoremainasunvarying.
Ingeneral,doughswhichwillbebakedinapantendtohavehigher
addedwaterlevelsthanthosewhichwillbebakedontraysortheovensole
(i.e.,free-standing).Intheformercase,asoftdoughwillmorereadilyflow
intothecornersofthepans,whereasinthelattercase,astifferdoughwill
levelsinthemanufactureofUK-stylebloomerswhichtraditionallyhavea
roundorovalcross-section.Toomuchwaterandthedoughwillflowduring
proofandyieldanuncharacteristicandunacceptableflatshape(
Cauvainand
Young,2008
).
Somebreadtypesdependontheproductionofasoftdoughtoachieve
therequiredcharacteristics.Inthem
anufactureoftraditionalFrench
themeasuredflour-waterabsorptioncapacityandabovethatusedforpan
breadproduction.Thesoftdoughcontributestotheeaseofdoughmould-
ingandavoidanceofthesqueezingoutofthelargegasbubbleswhichsig-
nificantlycontributetothecreationoft
hecharacteristicopencellstructure
formwhichstopsthemfromflowing,
andthesoftdoughalsocontributes
totherapidexpansionofthedoughpieceintheovenwhichyieldsahigh
specificvolumeproduct.
CauvainandYoung(2008)
discusstheroleofdoughconsistencyandits
impactonbread-cellstructure.Theyshowhowthegasbubblestructurein
stiffdoughcanbebrokendownandcontributetotheformationofareasof
damagedstructureinthebreadcomprisingcoarsecellstructureanddull-
colouredcrumb(see
Sections2.2.11
).
Althoughdoughconsistencymayvarywithproductandprocess,thereis
onedoughpropertythatiscommonlyavoidedinallcases,namelydough
stickiness.Inthebakeryproblems,doughstickinessareusuallyassociated
withthewaterleveladdedduringdoughmixing,andacommonreactionto
excessivelystickydoughinthebakeryistoreduceaddedwaterlevels.
Areductioninaddedwaterlevelmaywellimprovetheprocessabilityofthe
48
BakingProblemsSolved
dough,buthighwaterlevels
perse
areoftennotthemaincauseofdough
stickiness(
Cauvain,2015
).Inmanycases,doughstickinessarisesbecauseof
lackofdoughdevelopmentinthemixer;thegreaterthedoughdevelopment,
thehighertheaddedwaterlevelmaybe.Theothermajorcontributorto
apparentdoughstickinesscomesfromsubjectingthedoughtoshearforces
duringprocessing,suchasduringmoulding,ifthesecanbeminimisedthen
waterlevelscanbeoptimisedwithoutcompromisingdoughrheologyand
breadquality.
References
Cauvain,S.P.,2015.TechnologyofBreadmaking,thirded.SpringerPublishingInternational,
Switzerland.
Cauvain,S.P.,Young,L.S.,2008.BakeryFoodManufactureandQuality:WaterControl&
Effects,seconded.Wiley-Blackwell,Oxford,UK.
RawMaterials
Chapter|2
49
2.2.4Whateffectswillvariationsinflourproteincontenthave
onbakedproductquality?Howisthepropertymeasured?
Theproteincontentofflourisprobablythesinglemostimportantproperty
ofwheatflour.Perhapsmorecorrectly,weshouldrefertowheatproteinsas
thereismorethanonetypeofproteinpresent.Theschemeestablishedby
Osborne(1907)
ismostcommonlyusedforthegroupsofproteinsinwheat
whichcomprise:

Albumins,solubleindistilledwater.

Globulins,solubledilutesaltsolutions.


Glutelins,solubleindiluteacid.
Thetwomostimportantgroupsforbreadandfermentedgoodsarethe
prolaminesandtheglutelins.Theycontainthegluten-formingproteinswhich
inggasandincreasinginvolumeundertheinfluenceofheatandcarbon
dioxidegasreleasedbyyeastfermentation.Thepropertiesofwheatgluten
wererecognisedaslongagoas1729(
Bailey,1941
).
Gliadinandglutentinarethetwowheatproteincomponentswhichgives
wheatglutenitsspecialproperties.Thesecanbestbeappreciatedbymaking
adoughofflourandwaterandhandkneadingitunderrunningwater.As
timeproceeds,amilky-whiteliquidiswashedout,thisisthestarchandother
insolublecomponents.Eventually,allthatisleftisgreyish,lightbrownmass
withanextensiblebutalsoanelasticcharacter.Thisisthegluten,anditsgas
andwatchingitswell.Thequantityofglutenthatcanbeextractedvaries
withtheproteincontentoftheflour.
Breadandotherfermentedproductvolumesaredirectlyrelatedtothe
quantityofproteinpresent;thehighertheproteincontentoftheflour,the
greatertheproductvolume.Thispositiverelationshiphasbeenreportedbya
largenumberofobserversformanydifferentbreadmakingprocessesand
products(e.g.,
Cauvain,2015
).Thus,inanswertoyourquestion,variationin
proteincontentwillresultinpotentialvariationsinbreadandfermented
productvolume.Theywillalsoaffecttheliftobtainedwithlaminatedpro-
ductsbutwillhavenosignificanteffectonthevolumeofotherbakedpro-
ducts,thoughvariationsinproteincontentmayaffectotherproduct
attributes,e.g.,eatingqualityincakes.
Proteinabsorbswater,1.3gofwaterforeach1gprotein(
Cauvain,
2015
),sovariationsinproteinalsoaffectflou-waterabsorption.
Cauvain,2017
digestionoftheflourusingsulphuricacidinthepresenceofacatalyst.The
50
BakingProblemsSolved
forwheatthisinvolvesmultiplyingby5.7.Morerecently,Kjeldahlprotein
inthepresenceofoxygen(
Cauvain,2017
).
Flourproteinisalsocommonlymeasuredusingnearinfraredreflectance
(NIR)technology(
Cauvain,2017
).Thisprovidesafastandsimpletouse
However,itshouldbenotedthatNIRproteiniscalibratedagainstan
mentofprotein.
References
Bailey,C.H.,1941.AtranslationofBeccarislectureconcerninggrain.CerealChem.18,
555

561.
Cauvain,S.P.,2015.TechnologyofBreadmaking,thirded.SpringerPublishingInternational
AG,Switzerland.
Applications,seconded.DEStech,Lancaster,PA.
Osborne,T.B.,1907.TheProteinsoftheWheatKernel.CarnegieInstituteofWashington,
Washington,DC.
RawMaterials
Chapter|2
51
2.2.5Therearemanyreferencestoproteinandglutenquality
inthetechnicalliterature,howimportantaretheseproperties
forbreadandotherbakedproducts?
Asdiscussedinthepreviousquestion,flourproteincontentisprobablythe
mostimportantofallflouranalysesduetoitsrelationshipwithglutenquan-
tity.Inglutenwashingexperimentswithdifferentflours,wecannotonly
observedifferentquantitiesofgluten,butforthesameglutenmassfromtwo
differentflours,wemayobservethattherheologicalcharacter(i.e.,theway
Wethereforeseektohaveaglutenwhichhaslowresistancetodeformation,
minimalelasticityandmaximumextensibility.Breadandotherfermented
doughsgenerallyonlyexperienceproblemswithstickinesswhentheyare
subjectedtoshear,e.g.,asinmouldingorwithexcessiverecipewater
levels.
Thesheetingofdoughasfortheproductionoflaminatedproducts,pastries,
crackersandbiscuits,alsorequiresthattheyhaveanextensiblebutnotelastic
gluten.However,asrecipewaterlevelsinsuchproductsarelowerthanusedin
breadmaking,theglutentendstohaveamoreelasticnature.Toovercomethis,
itiscommontouserestingperiodsduringprocessingtoallowtheglutento
becomesofterandlesselastic.Itisnotsoeasytouserestingperiodswith
fermentedproductsduetothegasproductionbytheyeast.
Inbatter-typeproducts,suchascakes,glutenqualityisconsiderablyless
important,mainlybecauseitcannotformintheinitialmixingstagesdueto
lowviscosityofthesystemthatmakesthetransferofsufficientenergyand
thereforeglutendevelopmentdifficult.
BakingProblemsSolved
Chapter|2

Roberts/Dobraszczykdoughinflation
Thisdevicecanbefittedtostandardtextureanalysismachine.Thedough
ispreparedunderstandardconditionsandairpressureusedinflatesa
bubbletothepointofrupture.

Fundamentaldoughrheologymeasurements
tofundamentalrheologicalmeasurements,butasdoughisvisco-elastic
(i.e.,hasbothviscousandelasticproperties)anddeformationforcesare
remainsastenuousaswithothertests.

Large-scaledeformationtesting
Anumberoftestshavebeendevelopedbyworkersseekingtomore
closelymimicthebehaviourofdoughundernormalbakeryconditions.
Theteststendtobeproductorprojectspecificandnotincommonuseas
Furtherreading
Cauvain,S.P.,2015.TechnologyofBreadmaking,thirded.SpringerScience
1
BusinessMedia,
Switzerland.
Applications,seconded.DEStech,Lancaster,PA.
Dobraszczyk,B.J.,1999.Measurementofbiaxialextensionalrheologicalpropertiesusingbubble
inflationandstabilityofbubbleexpansioninbreaddoughs.In:Campbell,G.M.,Webb,C.,
Pandiella,S.S.,Niranjan,K.(Eds.),BubblesinFood.AmericanAssociationofCereal
Chemists,St.Paul,Minnesota,USA.
Faridi,H.,Faubion,J.M.,1990.DoughRheologyandBakedProductTexture.VanNostrand
Reinhold,NewYork,USA.
54
BakingProblemsSolved
2.2.7Wehavebeenusingaflourfortifiedwithdrygluten
forbreadmaking.Thebreadissatisfactorywhenmadeona
high-speedmixerbutsolesswhenweusealow-speedmixer.
resultswhenwechangemixers?
Dryglutenisobtainedbywashingoutthestarchfromawheat-flourdough.
Theprocessofmillingusedtoextractthewheatproteinsdiffersfromstan-
flourfromwhichthedriedglutenistobepreparedismixedwithwaterto
formadoughorbatterisformed.Arubberymassisformedasthegluten
hydratesandthedoughiskneaded(muchashappensinbreadmaking).
Thestarchiswashedout,andtheglutenmasswhichisleftiscarefullydried
gluten,i.e.,itsabilitytoformglutenafterhydrationanddoughmixing.
Typically,theproteincontentofthedryglutenwillbeintheregionof
70

75%drymatter.Insomevariations,thewheatflourmaybesuspended
inalkalineoracidicsolutionstoaidtheseparationoftheproteins.
Dryglutenabsorbsabout1.5timesitsownweightofwaterwhenitis
usedinbreadmaking.Theadditionofdryglutenmaybeusedtoboostthe
thedough.Itmaybeaddedtotheflourinthemill,oritmaybeaddedasa
dryingredientinthebakery.Dryglutendoesnotusuallyrequireprehydra-
tionbeforedoughmixing.Thewheatsourceofthevitalwheatglutenisnot
usuallyconsideredtobeimportantandprovidedthattherehasbeennoheat
denaturationoftheproteins,thentheoverallfunctionalityofthedriedgluten
islargelydictatedbytheproteincontentofthematerialused.
Theinputofenergyduringdoughmixingisanessentialpartofthe
Differentmixersimpartdifferentlevelsofenergytothedoughforagiven
mixingtimeandsoaremoreorlesseffectiveatdevelopingaglutenstruc-
ture.High-speedmixersimparthigherenergylevelstothedoughduring
mixingthanlow-speedmixers.Thisdifferenceremainstrueevenwhenthe
doughmixingtimewithlow-speedmixersislengthened.Thisisbecause
thelowspeedofmixingresultsinalowrateofenergytransfer.
Glutendevelopment,asmanifestedbyimprovedgasretention,isknownto
belinkedwiththerateofenergyinputtothedoughwithfasterratesofenergy
inputimprovingdoughgasretentionformanyflours(
Cauvain,2015
).This
effectisespeciallytrueforgluten-fortifiedflours,anditappearsthatmixersat
lowspeedsarelessabletomakefulluseofdryglutenadditions.However,
thefullreasonsforthedifferencearenotcompletelyunderstood.
Reference
Cauvain,S.P.,2015.TechnologyofBreadmaking,thirded.SpringerInternationalPublishing
AG,Switzerland.
RawMaterials
Chapter|2
55
2.2.8Whyistheproteincontentofwholemealbreadflour
typicallyhigherthanthatofwhitefloursbutthebreadvolumeis
commonlysmallerwiththeformer?
Proteinsaredistributedthroughoutthedifferentcomponentsofthewheat
berrybutthatdistributionisnot-uniform.Theretendstobelesstheprotein
inthecentralendospermportionsofthegrain(
KentandEvers,1994
).
Thisnon-uniformdistributionofwheatproteinismirroredbyanincreasein
thestarchcontent.Theprotein/starchgradientinthegraincross-section
reflectsthemannerinwhichtheendospermdevelopsinthegrowingplantas
thedifferentcomponentsaresynthesised.Thestarchgranulesarepacked
intocellswiththeproteinfragments.Thecellwallsofwheatendospermare
mainlycomposedofarabinoxylans.Surroundingthestarchyendosperm
isthealeuronelayerwithdense,thickcellwalls.Furtheroutinthegrain
cross-sectionarethedifferentlayerswhichcharacterisethebran.
Asthedistributionofproteinisnotuniformthroughoutthegrain,the
proteincontentoftheflourisoftenareflectionofthemillingprocessesused
tomanufacturetheflour.Bydefinition,wholemealflourrepresentsallofthe
graincrushedintofloursotheproteincontentofthefinalflourshouldbe
thesameoftheoriginalstartinggrain.Whiteflourisbasedontheseparationof
thestarchyendospermfromthesurroundingbranlayers,andtheytendtohave
around1%lessproteinthantheoriginalgrain(viz.wholemealflour).Thepre-
cisedifferenceintheproteincontentofthegrainandthewhiteflourproduced
fromitvariesslightlyaccordingtothemillingtechniqueemployed.
whichcommonlyyieldslowervolumeinthefinishedproductunless
modificationsaremadetothebreadmakingrecipeandprocess.Although
thereareproteinsinthebranparticles,theydonotreadilyformagluten
thisproteinmaybeconsideredasnon-functional.
Themechanismbywhichbranparticlesreducesdoughgasretentionarenot
fullyunderstood.Someviewssuggestthattheparticlesofbranpuncturethe
gascellwallsinthedough.However,itismorelikelythatthebranparticles
representareasofdiscontinuityandweaknessintheglutennetworkwhich
morereadilyallowthecoalescenceofsmallergasbubblesastheyexpand
duringproofandtheearlystagesofbakingandsopermittheescapeofsomeof
thecarbondioxidegasbeingproducedbytheyeast.Forthereasonsgiven
above,itiscommonpracticetoproducewholemealflourswithmuchhigher
proteincontentsthanthatofwhiteflours.Thisisdoneeitherbychoosinga
higherproteinwheatwithinthemillinggristorthroughthesupplementationof
themilledflourwithdried,vitalwheatgluten(see
Section2.2.7
).
Reference
Kent,N.L.,Evers,A.D.,1994.KentsTechnologyofCereals,fourthed.ElsevierScienceLtd.,
Oxford,UK.
56
BakingProblemsSolved
wholemealbreadandrollsdependingonwhichflourwe
purchase.Whatcharacteristicsshouldwelookforina
Wholemealfloursfallintotwomainca
tegories;stonegroundandroller-
general,stonegroundflourshaveagrea
terproportionoffinebranparticles
thantheroller-milledtype.Thepresenceofhighlevelsofbraninwhole-
mealfloursisresponsibleforthelowerbreadvolumethatisachievedby
comparisonwithwhiteflourfromthe
samewheat,despitethefactthatthe
whiteflourhasalowerproteincontent.Itisalsoknownthatfinerbranpar-
ticlestendtohaveaproportionallygr
eatervolumedepressingeffectthan
coarseparticles.
Inadditiontothebranparticlesizedi
fference,theremaybedifferences
intheendospermparticlesizeofthetwotypesofwholemealflour.Itis
likelythattheendospermparticlesize
ofthestonegroundflouriscoarser
thanthatoftheroller-milledtypebe
causetheendospermparticlesare
subjectedtoconsiderablyfewergrin
dingpassages.Onepossibleconse-
quenceofthisdifferenceisthatthe
endospermparticlestakelongerto
hydrate,andifyourmixingtimesareshort,youmaynotseethesame
extentofglutenformation.Youcan
checkthiswithafewsimpletrials
withextendedmixingtimes.
Theproteincontentofyourwholemea
lflourshouldcertainlybespeci-
fied.Thiswillreflecttheprotein
contentofthewheatschosenbythe
miller.Itispossibletoaddvitalwheat
glutentoboosttheproteincontent
ofyourmix,butglutenfortificatio
nislesseffectivewithslowerspeed
mixers(see
Section2.2.7
).
ThespecificationoftheHagbe
rgFallingNumber(orasimilar
measure)isasimportantwithwholem
ealfloursasitiswithwhiteflours,
andyoushouldalsoconsiderwhetheryoushouldspecifythewaterabsorp-
tioncapacityoftheflours.Youw
illneedtorememberthatthewater
absorptioncapacityisonlyaguide
astowhatwaterlevelyouwillneedto
actuallyusefordoughmixing(see
Section2.2.3
).Inthecaseofwhole-
mealflour,thisisanespeciallyimportantpointtobearinmindasthe
branandlargerendospermparticle
swillbeslowtohydrate.Thisoften
meansthatwholemealflourdoughsbec
omestifferduringpost-mixerpro-
cessing,andthiscanhaveanegativeimpactondoughhandlingproperties
andcontributetomoulderdamagean
dotherproductqualitylosses.You
shouldtrytomaximisethewateradditionsmadetowholemealflours,the
initialtackinessthatyouobservewhenthedoughhasfinishedmixingshould
begintodisappearwithinafewminutesduringprocessing.Optimisingthe
addedwaterlevelwillalsohelpyouoptimisedoughdevelopmentandthegas
RawMaterials
Chapter|2
57
2.2.10WhatistheFallingNumberofaflour,howisit
measuredandwhatvaluesshouldwespecifyforourflourmiller?
TheFallingNumberofaflourisrelatedtothelevelofcereal
alpha
-
amylasewhichispresentinthewheatafterharvesting.Theproductionofcereal
alpha
-amylaseisencouragedwithinthewheatgrainsiftheirmoisturecontent
issufficientlyhightowardsinthelastfewweeksbeforeharvesting.Suchcondi-
ThefullnameforthetestistheHagbergFallingNumbertestanditwas
originallydevelopedinSweden.Ittakesitsnamefromthebasisofthetest.
Aflour

watersuspensionisheatedwithinatubeheldinaboilingwater
bath.Themixtureisstirredfor60stoensureuniformityofthemixture.
pointatthetopofthetube,releasedandthetimetakenforthestirrertofall
throughthemixturetoalowerfixedpointinthetesttubeismeasured.The
timetakenforthestirrertofalldownthetubeisknownastheFallingNumber.
Thetestisbasedontheactionofthecereal
alpha
-amylaseonthe
gelatinisingstarchpresentintheflourwhichisprogressivelybrokendownby
theamylaseaction.Thetemperatureinthetestisdesignedtogivemaximum
enzymicactivityintheflour

watermixtureandtheFallingNumberchanges
accordingtothelevelofcereal
alpha
-amylasepresent;thehigherthecereal
alpha
-amylaselevel,thequickertheflour

waterpastethins,thefasterthe
stirrerfallsandthereforethelowertheFallingNumber.TheFallingNumber
includesthe60sstirringtimesothatthelowesttheoreticalnumberis60.
Inpractice,FallingNumbersover250aresuitableformostbreadmaking
processes.Aswellashavingtoomuchcereal
alpha-
amylaseactivity,itispos-
sibletohavetoolittleandFallingNumbersabove350indicatethattheflour
shouldbesupplementedwithaformofamylase(
Cauvain,2015
)tomaintain
gasproductionthroughtheprovisionofmaltoseforyeastactivity.Wesuggest
youspecifythatyourFallingNumberliesbetween250and280,thoughthe
actuallevelyourequirewillbespecifictoyourproductsandprocesses.
Thehigherthecereal
alpha
-amylaselevel,thegreaterformationofdextrins
duringbreadmakingandthemorelikelythattherecouldbeproblemswithbread
slicinginallbreadmakingprocesses.Inbulkfermentation,highcereal
alpha
-
amylaselevelswillleadtodoughsofteningduringthebulkstandingtime.
Reference
Cauvain,S.P.,2015.TechnologyofBreadmaking,thirded.SpringerInternationalPublishing
AG,Switzerland.
Furtherreading
Applications,seconded.DEStech,Lancaster,PA.
58
BakingProblemsSolved
2.2.11Whatisdamagedstarchinflour?Howisitdamagedand
howisitmeasured?Whatisitsimportanceinbaking?
Starchgranulesinflourhaveaflattenedroughlysphericalshapewhichis
50

m.Eachstarchgranulehasasurfaceorskin.Withinthedeveloping
wheatgrains,thestarchgranulesareembeddedinaproteinmatrixinthe
endosperm.Duringtheflourmillingprocess,theendospermisfragmented
bytheactionofthemillingsrollsorstones.Someofthestarchgranulesare
exposedtohighpressuresduringthemillingprocess,andtheirsurfacesmay
bebecomemechanicallyrupturedordamaged.Thedamagetostarchgran-
ulestypicallyoccursduringthereduction(smoothrolls)stageofrollermill-
adjustedtogivemoreorlessstarchdamageaccordingtotherequirements
forthefinalflour.
Damagedstarchissusceptibletoattackby
alpha
-amylase,andthisaction
beusedforthemeasurementofthedamagedstarchlevelinflours.Along-
devisedby
Farrand(1964)
,andformanyyears,thelevelofdamagedstarch
inflourswasreferredtoinFarrandUnits.Morerecently,themostimportant

Gibson
).

DonelsonandYamazaki,1968;AACC,1995
)based
ondigestionofthedamagedstarchbyfungal
alpha-
amylasewiththe
valueexpressedasapercentage.

WiththeChopinSDmatictestwhichprovidesanautomaticmeasurement
ofdamagedstarch(
Cauvain,2017
).

UsingNIRspectroscopywithcalibrationsthatarerelatedtootherstan-
Theimportanceofdamagedstarchismainlyforbreadmaking.Damaged
starchabsorbstwiceitsownweightofwaterincontrastwithundamaged
starchwhichonlyabsorbsaround40%ofitsownweight.Thishighwater
absorbingcapacitymeansthatthedamagedstarchmayaccountforabout
16%ofthetotalflour-waterabsorption,avaluewhichissimilartothatfor
theproteinitself(
Cauvain,2015
).Thecontributionthatdamagedstarch
makestoflour-waterabsorptionhasmadeitanessentialelementofbread
flourspecifications.
Theupperlimitsforstarchdamagearenotwelldefinednorunderstood.
alpha
-amylaseactivityisan
importantoneasexcessiveamylase
activityleadstodextrinformation
RawMaterials
Chapter|2
59
andthereleaseofwaterintothedoughwhich,inturn,cancausedough
softeningduringwithbreadmakingprocesseswhichemployperiodsof
bulkfermentation.
Veryhighlevelsofstarchdamagemayleadtolossofbreadquality,
includingamoreopen(largeraveragesize)cellstructureandgreyingofthe
crumbcolour.
Farrand(1964)
observedsuchqualitylossesandrelated
thesetothestarchdamageandflourproteinlevels.Hispremisethatthe
damagedstarchlevelshouldnotexceed,the(protein)
2
dividedby6isno
longerabsolutelyrelevant,buttheprinciple,thatthehighertheflourprotein,
thehigherthestarchdamagethatcanbeaccommodatedremainsarelevant
ruleofthumb.
References
alpha
-amylaseunder
specifiedconditions.
Cauvain,S.P.,2015.TechnologyofBreadmaking,thirded.SpringerInternationalPublishing
AG,Switzerland.
Applications,seconded.DEStech,Lancaster,PA.
CerealChem.45,177

182.
Farrand,E.A.,1964.Flourpropertiesinrel
ationtothemodernbreadprocessesinthe
UnitedKingdom,withspecialreferenceto
alpha
-amylaseandstarchdamage.Cereal
Chem.41(March),98

111.
measurementofstarchdamageinwheatflour.J.CerealSci.15,15

27.
60
BakingProblemsSolved
2.2.12Whatcharacteristicsshouldwespecifyforwhitebread
flourandwhy?
Thebreadmakingpotentialofflourisstronglyinfluencedbytheprotein
presentinthewheat.Theseproteinshydrateandwiththeinputofenergy
whichshouldbetakenintoaccountwhendecidingonaparticularflourspeci-
fication,andthereareprocessfactorstoconsider,suchaswhichbreadmaking
processyouareusingandwhattypeofproductyouaremaking.
Asaguide,youshouldconsiderthefollowingasaminimumforwhite
flour:

Proteincontent

Around13%onadrymatterbasis.This
figureshouldincreasebyabout1%
ifyouareusingaprocesswhich
usesbulkfermentationtomaturethedoughbeforeprocessingorifyou
aremakingfree-standing,hearth-oroven-bottomtypebreads.Asa
generalrule,thehighertheproteinlevelintheflourthegreateritsgas
retentionpotentialandthereforeth
egreatertheresultantbreadvolume
andcrumbsoftness.

Ameasureofthepurityofthewhiteflour;thatisthelevelofbran
particleswhicharepresent.ThisisoftenmeasuredasashorGCF
(see
Sections2.2.1and2.2.2
).Thepresenceofbranhasanegative
ofthedough.

Thewaterabsorptioncapacityoftheflourasthisisanindicatorof
howmuchwaterwillneedtobeaddedatthedoughmaking.Anumberof
differentfactorsaffectthewaterabsorptioncapacity(see
Section2.2.3
).
Themeasuredwaterabsorptioncapacityisonlyaguideastothelevel
thatwillbeusedinthebakery.Itisusualfortheactuallevelofwater
addedtodoughtobereducedwhenmakingfree-standingbreadsasthis
(
CauvainandYoung,2008
).

HagbergFallingNumber

Typically,thisshouldbeabove250seconds
(see
Section2.2.10
).

Proteinquality

Thisisusuallyassessedbymeasuringtherheological
propertiesofaflour

waterdough.Ingeneral,theflourshouldpossess
goodstability.Thereareanumberofdifferenttestswhichcangive
Section2.2.5
,
Cauvain(2016)
.

Flourtreatmentsandadditives

Ideally,theflourshouldbeuntreated,
butifthisisnotpossible,anyadditionsshouldbekepttoaminimum.
Commonadditionsareascorbicacid(AA)asabreadimproverand
RawMaterials
Chapter|2
61
alpha
-amylase.Ifyouareusingabreadmakingprocessinwhichtheflour
addtheminthebakeryaspartoftherecipe.Anyadditionstotheflour
shouldbediscussedwithyourmillersupplier.
References
Applications,seconded.DEStechPublications,Lancaster,PA.
Cauvain,S.P.,Young,L.S.,2008.BakeryFoodManufactureandQuality:WaterControl&
Effects,seconded.Wiley-Blackwell,Oxford,UK.
62
BakingProblemsSolved
2.2.13Asenzymessuchas
alpha
-amylaseareinactivatedby
heatduringbaking,isitpossibletouseheattreatmentofflourto
inactivatetheenzymesinlowHagbergFallingNumberflours
beforebaking?
Thetemperatureatwhich
alpha
-amylaseisinactivateddependsonitssource.
Therearethreecommonsources;fungal,cerealandbacterialwhichare
inactivatedatincreasinglyhighertemperatures(Cauvain,2015).Asyou
areaskingaboutflour,thesourceofthe
alpha
-amylaseisreferredtoas
cereal(commonlyfromwheat,ryeorbarley).
Theexposureofflourtoheatbringsaboutanumberofdifferentchanges.
Inadditiontoinactivationofthe
alpha
-amylasetherewillbe:

Alossofmoisture.

Thepotentialfordenaturationoftheprotein.

Changesintheswellingandgelatinisingcharacteristicsofthestarch.
Whenheatisappliedtoflour,itquicklylosesmoisture,butasthe
moisturecontentfallstoaround8%,therateofmoisturelosswithcontinued
heatingslowsdown.Itappearstobethatfromthispointonthatsomeofthe
moreprofoundchangestakeplaceinflourproperties.
Atlowlevelsofheatinput,areductionintheextensibilityoftheflour
isusuallyobserved.Prolongedheatingleadstocompletedenaturationofwheat
proteinsandtheylosetheirabilitytoformacohesiveglutennetworkindough.
Dryheattreatmentofflourbringsaboutchangesinstarchproperties
whichareanalogoustochlorination,andthistypeoftreatmentisusedto
replacechlorinationforfloursintendedforthemanufactureofhigh-ratio
cakesandsomeotherbakedproducts(see
Section2.2.17
).
Heattreatmentoffloursshouldnotbeusedwheretheproductisintended
forbreadmakingduetothepotentialforpartialortotaldenaturationofthe
gluten-formingproteins.Thus,inactivationof
alpha
-amylasebyheatshould
notbeseenasameansofreducingtheadverseeffectsofcerealamylasein
breadmaking.
Insomespecialityflours,i.e.,thosedestinedforuseinthemanufacture
ofsoupsandsauces,inactivationof
alpha
-amylaseisbeneficial.Inthese
cases,thechangestotheproteinsandstarchareacceptableastheycontribute
toadiscernableincreaseinbatterviscosity.Thechangeswhichheatbrings
aboutincreasethesusceptibilityofstarchtoamylaseattackwhichwould
reducethebatterviscosity.Withtheamylaseinactivated,batterviscositycan
bemaintainedatanacceptablelevel.
Reference
Cauvain,S.P.,2015.TechnologyofBreadmaking,thirded.SpringerInternationalPublishing
AG,Switzerland.
RawMaterials
Chapter|2
63
2.2.14WeareconsideringmakingtraditionalGerman-typerye
Doyouhaveanysuggestionsastowhatcharacteristicswe
shouldhaveintheryeflour?
Ryegrainismoresusceptibletopre-harvestsproutingthanwheat.Thestarchin
ryeflourgelatinisesatalowertemperaturethanwheatstarch,andtherefore,rye
flourismuchmoresusceptibletoenzymicdegradationby
alpha
-amylase.
Anotherfundamentaldifferenceisthattheproteinspresentinryedonotforma
glutennetworktoanysignificantdegree,andthepentosansinryeareessential
forwaterbindingtoformadough.Thus,althoughsomeofthegrainandtesting
methodsarecommontowheatandryeflours,differentemphasesareplacedon
theresultswhenincorporatedintoflourspecifications.
Thekeyqualityrequirementsforryefloursareasfollows:

MinimumHagbergFallingNumberof90s.

Pentosancontentof7

10%.

Waterabsorptioncapacity68

75%.
Thewaterabsorptioncapacityofryeflouristypicallyhigherthanthatof
wheatflourduetothemuchhigherlevelofpentosansinryeflour.
Itiscommonpractisetomeasurethegelatinisationcharacteristicsof
ryeflour.Thetechniquecomprisesheatingaryeflour

watermixtureata
constantratefrom30to90

Candfollowingthechangesinviscositywhich
occuroverthistemperaturerangewhilethemixtureisstirred.Atypical
instrumentusedforthispurposewouldbetheBrabenderAmylographwhich
recordschangesinviscosityinAmylographUnits(AU).TheAUvaluewill
berelatedtotheenzymicactivityintheflour,thelowertheAUvaluethe
highertheenzymicactivityandconsequentlythepoorertheshapeofthe
loavesandthelowertheirvolume.AtverylowAUvalues,splitsandother
defectsmaybeseeninthebreadcrumb(see
Fig.2.2
).
Arangeofryefloursareoftenavailablevaryingfrom100%wholegrain
throughtoarefinedflourwithlowbrancontentwhichallowtheproduction
ofawiderangeofryebreadtypes.Itisworthnotingthattheacidificationof
aretwocommonwaysofrestrictingtheenzymicactivityinthefinaldough.
�Flour with 1000430110 (AU)
FIGURE2.2
RyebreadmadewithflourswithdifferentAmylographviscosities(reproduced
withpermissionofBrabenderGmbH&Co.KG).
64
BakingProblemsSolved
2.2.15Wewishtoaddnon-wheatfibrestosomeofourbaked
productstoincreasetheirhealthiness.Whatfibrescanweused,
inwhatproductsandwhatpotentialtechnicalproblemsshould
webeawareof?
Therearealargenumberoffibresfrommanydifferentsourcesthatmightbe
andhavebeenproposedasadditionstobakedproducts.Therangeissowide
thatitisnotpossibleinashortanswertodomorethanoffersomegeneral
pointersandafewexamples.
Ifyouaregoingtomakehealthclaims,thenitisimportantthatyou
firstmakesurethatthefibresthatyouareproposingtousearepermitted
asadditionstobakeryfoodsandtoidentifyanyrestrictionsthatmightapply.
Youshouldalsocarefullycheckthepotentialvalidityandpermissibilityof
anyhealth-relatedclaimswhichmightbeusedontheproductpackagingor
Chapter|2
maintainasuitablebatterviscositymayalsorequireadjustmentofthesugar
levelsintherecipetobemade.Youwillneedtobecarefulthatthesugar
andliquidlevelsdonotexceedacceptablelevelsfortheflourthatyouare
using(e.g.,treatedoruntreated).Inpractice,theleveloffibreadditionisrel-
ativelylowandcanusuallybeincludedasflourwhenbalancingrecipes.
Fibrescomeinmanydifferentformsfromfinepowderthroughflakesto
wholegrainsandseeds.Choosingtheformyouwanttousewilldependonthe
incorporateddirectlyintothedoughorbatter.Someofthefibrousgrainsand
seedshaveotherinterestingattributesrelatedtotheirnutritionalproperties.
Inmanycases,theattractionofusingaparticularfibreisthattheyhavea
colourwhichislighterthanthatofwheatbranandsimilartothatofwheat
flour.Theadditionofsuchmaterialsallowsyoutoincreasethefibrecontent
oftenseenasanadvantageindeliveringthenutritionalbenefitsoffibreto
children.
Furtherreading
Hartikainen,K.,Katina,K.,2012.Improvingthequalityofhigh-fibrebaking.In:Cauvain,S.P.
(Ed.),BreadMaking:ImprovingQuality,seconded.WoodheadPublishingLtd,Cambridge,
UK,pp.711

745.
Lorenz,K.J.,Kulp,K.,1991.HandbookofCerealScienceandTechnology.MarcelDekker,
NewYork,NY.
McCleary,B.V.,Prosky,2001.AdvancedDietaryFibreTechnology.BlackwellScience,Oxford,UK.
66
BakingProblemsSolved
2.2.16Whyisflourparticlesizeimportantincakemaking?
Whiteflourwhichisusedincakemakingiscomposedmainlyofendosperm
fragmentswhichhavebeenseparatedfromthesurroundingbranduring
themillingprocess.Themaximumparticlesizeisfixedbythescreensizes
intheplansiftersinthemillbuttypicallyfallsaround150
m.Ifwewere
toexamineastraightrunwhiteflour,wewouldfindsomefragmentsof
theoriginalproteinmatrix(
m),somestarchgranulesfreedfromthe
proteinmatrix(upto45
m)withtheremainderbeingendospermfragments
ofvaryingsizesuptothemaximumscreensize.
Incakemaking,thewheatstarchplaysasignificantroleinforming
thecakestructureasitcontrolstheb
atterviscositydu
ringheatingand
Chapter|2
2.2.17Whatisheat-treatedflourandhowcanitbeused?
Themodificationofwheattoproduceheat-treatedflourorthedirectheat
treatmentofflourmaybeusedtoachieveanumberofdifferentchangesin
thefinalflourproperties.Wecanbroadlyclassifythetypeofheattreatment
Steamtreatmentofwheatiscommonlyusedtoinactivatetheenzymes
whicharepresentsothatthesubsequentflourmaybeusedasathickening
agent,forexample,intheproductionofsoups.Withoutinactivation,any
cereal
alpha
-amylasewhichispresentwouldactonthedamagedstarchand
thesubsequentreleaseofwaterwouldcausethinningofthesouporsauce.
Steamtreatmentofbothwheatandflourmaybeusedtoinduceadegree
ofgelatinisationinwheatflourwhichhelpswithitspotentialfunctionasa
thickeningagent.Steamtreatmentmayalsohaveasmallreducingeffecton
thenumbersofviablemicroorganismspresentintheflour,butthetreatment
isusuallyinsufficienttosterilisethematerial.
Dryheattreatmentofwheatandflourhasalonghistory.Intheearlier
yearsofthe20thcentury,itwasusedtomodifytheextensibilityofgluten
Kent-Jones,1926
),butsuchusesarenolongerin
commonpractice.
Themainapplicationofdryheattreatmenttowheatandflourisinthe
preparationofhigh-ratiocakefloursasanalternativetochlorination(see
Section2.2.18
).Anumberofpatentsweredevelopedwhichestablishedthenec-
essaryheatingconditionsrequiredtoachievethenecessarymodificationof
flourproperties(
).Treatmenttem-
peraturesnormallyexceed100

Crisingtoaround140

C,andasthetreatment
temperatureincreases,theresidencetimerequiredtoachievethemodification
decreasesfromseveralhourstoafewminutes.
Themechanismoftheimprovingeffectfromdryheattreatmentisnot
clearbutislikelytobeassociatedwithsomemodificationofthesurface
propertiesofthestarchpresentinthefinalflour.Attheendofthetreatment
process,theflourisverydryanditisclearthatthelossofmoistureisasso-
ciatedwithachievementofthenecessarychangesintheflour,butthelow
moisturecontentoftheflourisnotpartofthemechanismofimprovement.
Whenthedryflourisrehydratedconsiderableheatcanbegivenoff

knownasheatofhydration

andunlesscompensatorystepsaretaken,this
mayleadtoundesirableincreasesincake-battertemperaturesandpremature
releaseofcarbondioxidegas.
References
Cauvain,S.P.,Dodds,N.J.H.,Hodge,D.G.,Muir,D.D.,1976.BP1,444,173.HMSO,London,UK.
Doe,C.A.F.,Russo,J.V.B.,1968.BP1,110,711.HMSO,London,UK.
Kent-Jones,D.W.(1926)AStudyoftheEffectsofHeatuponWheatandFlour,Especiallyin
RelationtoStrength.ThesispresentedtoLondonUniversity,UK.
68
BakingProblemsSolved
2.2.18Whatischlorinatedflourandhowisitused?
Thetreatmentofflourwithchlorinegaswasfirstidentifiedinthe1920s
andwasusedforthemodificationofthecakemakingpropertiesofflours
formanyyearsintheUnitedKingdom,theUSA,Australia,NewZealand,
SouthAfricaandmanyothercountrie
s.Theuseofchlorinationforcake
flourtreatmentwaswithdrawnfromtheUnitedKingdomin2000(
The
MiscellaneousFoodAdditive(Am
endment)Regulations,1999
).Inmany
countries,ithadneverbeenpermitte
d,andinmanyothercountrieswhere
ithadbeenpermitted,ithasalsobeenwithdrawn.TheUSAremainsthe
maincountrywhereitisstillpermittedtomodifythecakemakingproper-
tiesofflour.
Chlorinetreatmentofflourpermitstheraisingofrecipesugarand
liquidlevelstomaketheso-calledhigh-ratiocake(i.e.,arecipeinwhichthe
addedsugarandwaterlevelsbothexceedtheflourweight).Theprinciple
benefitofthehigh-ratiocakerecipeisthatproductmoisturelevelscan
beincreasedwithoutadverselyaffectingthemould-freeshelf-lifeofthe
product.Thehighermoisturelevelconfersamoretendereatingqualityto
thefinalproduct.Iftheflourhasnotbeenchlorinatedandisusedwitha
high-ratiorecipethanthecakestructurewillcollapse,withlossofcrumb
structure,theformationofdense,dark-colouredstreaksandtheproduct
eatingqualitybecomespasty.
Chlorinetreatmentofflourisachievedbyblendingthegasthrough
rineonthebasisofflourweight.Thehigherlevelsarecommonlyusedto
treatflourintendedforthemanufactureoffruitedcakes.Thegaseoustreat-
menthasanumberofeffectsonflourquality,butonlyasmallproportionof
thegasusedactuallyconfersthebeneficialeffectstotheflour.Insummary,
thechlorinegasisusedasfollows:

Around50%ofthelevelusedisabsorbedbytheflourlipids(typically
around2%oftheflourmass)butappearstoplaynosignificantpartin
theimprovingaction.

Around25%denaturestheflourproteins(i.e.,preventtheformationof
gluten)butplaysnomajorroleinthecakeimprovingeffect.

Theremaining25%orsoreactwiththestarchgranules,andthisisthe
maincakeimprovingeffect.Itappearsthatthechlorinereactswith
theproteinsassociatedwiththesta
rchgranulesandmakesthemmore
hydrophobic.Thereisalsoevidencet
hatchlorinetreatmentincreases
theexudationofamylosefromwithin
thestarchgranules,butthatthere
isnochangeinthegelatinisationtemperatureofthestarch(
Cauvain
).
RawMaterials
Chapter|2
69

Theactionofchlorineistobleachtheflourpigmentssothatawhiter
flourandbrighterproductcrumbcolourareachieved.

TheflourpHislowered,andcommonlythiseffectisusedasacrude
measureofthelevelofchlorinationachieved.Moreaccurateassessment
IntheUnitedKingdomandelsewheretheheattreatmentoffloursfor
cakemakinghasreplacedchlorination(see
Section2.2.18
).
References
Cauvain,S.P.,Gough,B.M.,Whitehouse,M.E.,1977.Theroleofstarchinbakedgoods.Part2.
Theinfluenceofthepurificationprocedureonthesurfacepropertiesofthegranules.Starke
29(March),91

95.
TheMiscellaneousFoodAdditive(Amendment)Regulations,1999.S.I.1999No.1136.HMSO,
London,UK.
70
BakingProblemsSolved
2.2.19Whatcharacteristicsshouldwespecifyforcakeflour?
Incakemaking,themainstructurebuildingblockisthewheatstarchratherthan
theprotein,andthismeansthatwhenitcomestospecifyingtheflour,manyof
theprotein-basedmeasurementshavelimitedrelevance.Enzymicactivityis
limitedincakebatters,inpartbythelowwateractivityduetothesugarcontent,
andthisalsohasanimpactonthelistofpropertieswhichneedspecifying.
Ingeneral,cakefloursarederivedfromsoft-millingwheatsandtendto
attempttolimitglutenformationinthebatter.Althoughsuchthinkinghas
littlerelevancetoday,itremainsthecasethatcakefloursarespecifiedwith
lowproteincontents.Theexceptionisflourintendedforthemanufactureof
fruitcakeswherethepresenceofextraproteincontributestothesuspension
ofthefruitandotherparticulatematerialsinthebatterandbakedproduct.
Cakeflourswhichareintendedforuseinhigh-ratiocakemakingareusually
treatedinsomeway.High-ratiocakesrecipesarecharacterisedbyhavingsugar
andliquidlevelswhichareindividuallyandcollectivelyhigherthantheweight
offlour.Twoformsoftreatmentareused,bothofwhichmodifythegelatinisa-
tionpropertiesofthestarchintheflourthoughbyquitedifferentmeans.One
formoftreatmentiswithchlorinegas(see
Section2.2.18
),buttheuseofchlori-
nationhasbecomeincreasinglyrestrictedaroundtheworld.Dryheattreatment
(see
Section2.2.17
)hasreplacedchlorinationinmanycountries.Thelevelof
chlorinationorheattreatmentappliedinthemanufactureofcakeflourmay
varyaccordingtothepotentialuseoftheflour.Forexample,high-proteinflours
intendedfortheproductionoffruitedcakesmayreceivegreatertreatmentthan
thoseintendedforspongeorbarcakeproduction.
Anotherkeypropertyforhigh-ratiocakefloursisthereductionofthe
particlesizeoftheflour(see
Section2.2.16
)eitherbyregrindingorair
classificationoracombinationofbothmillingtechniques.
Unlikemanybreadflours,itisnotusualtoaddtechnologicallyfunctional
ingredientstocakeflours.Statutoryorvoluntarynutritionaladditionsmay
bemade.
Youwillonlyneedtospecifyalimitednumberofcharacteristicsfor
cakeflours.Typically,theywouldbe:
FlourcharacteristicLow-ratiocakeflourHigh-ratiocakeflour
Moisture(%)1414
Proteincontent(%asis)8

10(up12forfruitcake)7

10(upto12forfruitcake)
Particlesize(

m)Upto150
,
90
TreatmentNoneChlorinationordryheat
Traditionally,somecakefloursuppliescontainedraisingagentsto
providecarbondioxideduringbaking.Theyarereferredtoasself-raising
flourtendstomeetthespecificationforlow-ratiocakeflour.
RawMaterials
Chapter|2
71
2.2.20Wehavehadsomewholemealflourinstockforawhile
andnoticedthatithaspasseditsusebydate.Canwestilluseit?
Andwhatarethereanyrelatedissueswithwhiteflours?
Thequalityofallwheatflourschange
swithstoragetime;insomecases,
thechangesmaybeadvantageousandinothersdetrimental.Wholemeal
flourhasahigherlipidcontentthanwhitefloursandismorepronetopro-
blemsassociatedwithrancidity.Thel
owmoisturecontentandwateractiv-
ityofwholemealflourwillensureth
atmicrobialspoilageisunlikelyto
occur.However,thereisapotentialf
orrancidityfromenzymecatalysed
changesintheflouroil,andthisisakeyfactorinlimitingitsshelf-life.
Theotherpointtoconsideristhepote
ntialforinsectinfestationwhich
mightoccur.Werecommendthatyo
2.2.21Whataretheactivecomponentsinself-raisingflour?
Self-raisingflourscontainsodiumbicarbonateandasuitablefoodgradeacid.
Whenusedinbaking,thebicarbonateandacidreacttogeneratecarbondioxide
gas.Self-raisingfloursaremostcommonlysoldthroughtheretailtradeand
asanalternativetoseparateadditionsofplainflourandbakingpowder.
Thelevelofaddedbakingpowderisusuallygovernedbyaformof
regulationwhichspecifiesthevolumeofcarbondioxidegasthatisevolved
theactivecomponentsandlossofcarbondioxidegasduringtherelatively
longstorageperiodsforsuchflours,theratesofadditiontothefreshflour
willbesomewhathigherthanrequiredbylegislation.Forexample,theUK
BreadandFlourRegulations(1996)
specifiesthatself-raisingflourshould
yieldnotlessthan0.4%ofavailablecarbondioxide,butcommonlyratesof
additionwilldeliveraround0.8%whenfreshlyprepared.Thelatterlevel
equatesto1.56%oftheflourweightbeingsodiumbicarbonatewiththe
levelofacidadditionbeingdependentonthechoiceofacid.
Anumberofdifferentfoodacidsmaybeusedintheproductionof
self-raisingflour.Theyincludethefollowing:

Acidcalciumphosphate(ACP),monocalciumphosphate(MCP).

Sodiumacidpyrophosphate(SAPP).

Sodiumaluminiumphosphate(SALP).

Creamoftartar,potassiumhydrogentartrate.

Glucono-deltalactone.
Eachacidcomponentwillbeaddedaccordingtoitsneutralisingpowerwith
sodiumbicarbonate(
Thacker,1997
)(see
Section2.6.8
).Therateatwhichcar-
amixtureoftwoacidsmaybeusedtoprovideaso-calleddoubleactingbaking
powderwhichprovidesforbothearlyandlatecarbondioxidereleaseduringthe
manufacturingprocess(see
Section2.6.9
).
References
Thacker,D.,1997.Chemicalaeration.In:Bent,A.J.(Ed.),TheTechnologyofCakeMaking,
sixthed.BlackieAcademic&Professional,London,UK,pp.100

106.
TheBreadandFlourRegulations,1996.S.I.1996/1501.HMSO,London,UK.
RawMaterials
Chapter|2
73
2.2.22Wehavechangedsuppliersofourself-raisingflourand
findthatwearenotachievingthesameproductvolumeas
before.Ifweadjusttherecipebyaddingmorebakingpowder
we,findthattheproductstendtowardscollapse.Canyou
explainwhyandhowdoweovercometheproblems?
Self-raisingflourscontainthemixtureoffoodgradeacidsandsodiumor
potassiumbicarbonatethatisrequiredforthegenerationofcarbondioxide
gas(see
Section2.2.21
).Itispossibleforthelossofgassingpowertooccur
withstoragetime,butthisisnotusuallyasignificantproblemaslongasthe
flouriskeptdry.
Inmanypartsoftheworld,therearestandardsgoverningthevolumeof
carbondioxidegaswhichshouldbereleasedfromself-raisingflour,but
yourpreviousfloursupplywasprovidingmorethantherequiredminimum,
andthisiswhyyouaresufferingfromalackofvolume.However,thefact
thatyourproductscollapsewhenyouaddextrabakingpowdersuggeststhat
thisisnotthemostlikelycauseofyourproblem.
Thedifferentfoodgradeacidswhicharepermittedforuseinself-raising
flourhavedifferentratesofreactionwithsodiumorpotassiumbicarbonate
(see
Section2.6.8
).Thisisimportantincontrollingthereleaseofcarbon
dioxideduringprocessing;tooearlyandtheproductstendtolackvolume,
toolateandtheproductsmaytendtocollapse.Thedatain
Fig.2.3
compare
theratesorreactionfortwocommonlyusedfoodgradeacidswithsodium
bicarbonate.Fromthedescriptionoftheproblemthatyouhavegiven,
itwouldappearthatyournewsourceofself-raisingflourisgivinganearly
releaseofcarbondioxide,andthelevelofextrabakingpowderthatyou
haveaddedtocompensateissimplytoohigh;trygraduallyreducing
productvolumewhileavoidingcollapse.
0
20
40
60
80
100
120
140
160
180
200
0246810
Time (minutes)
Gas volume (ml)
SAPP 10
MCP
FIGURE2.3
Ratesofreactionoffoodgradeacids.
74
BakingProblemsSolved
2.2.23Whatareorganicflours,howdotheydifferfromother
floursandwhatwillbethedifferencestothebakedproduct?
Thetermorganicreferstothemannerinwhichthewheathasbeenfarmed
andturnedintoflourandsubsequentlybakedproducts.Organicfarminguses
Chapter|2
2.2.24Whatcharacteristicsshouldwespecifyforourbiscuit
andcookieflours?
Therangeofbiscuitandcookieproductsisquitewide,soitisdifficultto
provideaflourspecificationthatwillcoveralltypes.Theflourproperties
opmentinthedoughisdesirableornot.Thelevelofglutendevelopmentin
biscuitsismuchlessthanthatrequiredforbreadmaking(
CauvainandYoung,
2007a
),andwewouldreasonablyexpectthatingeneral,biscuitandcookie
flourswillbelowerinproteinwithmodestgluten-formingpotential.
Evenforlaminatedbiscuittypeslikecrackers,therequiredprotein
moulded,short-doughbiscuits.Thegristforbiscuitflourswillbebasedon
thesoftermillingwheatswithalimited,butoftennecessary,proportionof
hardermillingwheats.Typicalbiscuitflourproteincontentswillvaryfrom
9%to11%basedona14%moisturebasis.
Proteinqualitymaybemeasuredusingstandardtestssuchasthe
Brabender
r
Extensograph
r
ortheChopinAlveograph(
Cauvain,2017
).Such
testsaremoreapplicabletobiscuittypeswhichundergosomeformofsheeting
duringprocessing.Thesheetingcontributestoglutenformationandhighlevels
ofglutenformationwillexacerbateshrinkageoftheproductsduringproces-
singandbaking.Ingeneral,flourwithlowExtensograph
r
resistancewith
significantextensibilityispreferred(
CauvainandYoung,2007b
).
Theflourashorcolourmaybespecifiedthoughthereislimitedevidence
tosuggestthatthesepropertiesaredirectlyrelatedtoflourperformancein
themanufactureofbiscuits.Thespecificationofflour-waterabsorption
capacityisnotnecessary,evenforcrackerflours,becausemostbiscuit
andcookiedoughsaremadewithaslittlewateraspossibletoreducethe
potentialforglutendevelopmentandtolimittheamountofwaterthatmust
beremovedduringsubsequentbaking.
Mostfloursdestinedforbiscuitproductionarenowuntreatedandany
modificationtotheflourperformanceisusuallycarriedoutinthebakery
throughrecipeadditions,e.g.,theadditionofproteolyticenzymesorsodium
References
andApplications,seconded.DEStechPublishing,Lancaster,PA.
Cauvain,S.P.,Young,L.S.,2007a.BakedProducts:Science,TechnologyandPractice.
BlackwellPublishing,Oxford,UK.
1
BiscuitInternational:
Hamburg,Germany,pp.54

57.
76
BakingProblemsSolved
2.3FATS
2.3.1Whatarethecriticalpropertiesoffatsformakingbread,
cakesandpastries?
Toansweryourquestion,itisfirstnec
essarytobeclearaboutourdefini-
tionofafat.Inthebakery,thisisusuallythetermgiventoamaterial
whichisablendofliquidoilsands
olidfatsfromdifferentsources,
Podmore(1997)
providesacomprehensive
reviewofthenatureandstructureoffats.Thebasicbuildingblocksoffats
arethefattyacidsofwhichthereareth
ree.Thefattyacidsofthetriglycer-
idemaybethesameasoneanotherordifferent.Allnaturaloilsandfats
aremixturesofglycerides,andthepr
opertiesoftheindividualfatsand
oilsdependonthequantityanddistrib
utionofthedifferentglycerides
whichmaybepresent.
knowledgeofthecompositionofacompoundfatcanbeuseful.Thisiscom-
monlyobtainedusinggaschromatographyorhighperformanceliquidchro-
matography.However,suchanalyticaltechniquesrequireexpensiveand
specialisedequipmentwhichisnotwithinthescopeofmanylaboratories.
Thefattyacidcompositionisrelatedtoothermorereadilymeasurableprop-
ertiesoffatsandoils.
Areadilyknownmeasurementisthe
iodinevalue
whichmeasuresthe
proportionofdoublecarbonbondsinthefatandindicatesthedegreeofsatu-
rationpresent.Insomefattyacids,adjacentcarbonatomsinthechainmay
bejoinedbyadoublebondsothatfewerhydrogenatomsareattachedthan
remainingbondsareformedwithtwoindividualhydrogenatoms.
Traditionally,theslipormeltingpointofafatwasusedtocharacter-
iseitsperformanceinbaking.However,asmanycommercialfatsarecom-
poundmixturesoftriglyceridesthemeltingpointisoftenspreadoverawide
rangeoftemperaturessoithaslimitedvalue.Itisnowmorecommonto
refertothesolidfatindex(SFI)ofafatwhichconsiderstheproportionofa
compoundfatwhichissolidatagiventemperature.
Whichevernomenclatureisusedthetemperatureatwhichthemeasurement
ismadeshouldbequoted,e.g.,NMR
20
indicatesthepercentageofsolidfat
presentat20

C(see
Fig.2.4
).
Inthepast,measuresoffatfirmn
beenusedtoindicatethecharacteristicsofgivenfats,e.g.,Cvalues
(
Haighton,1959
).Thefirmnessofafatatagiventemperatureisstrongly
RawMaterials
Chapter|2
77
influencedbytheproportionofoiltosolid;however,thisisnottheonly
relevantpropertyoffattobeconside
red.Solidfatsmayexistindifferent
crystallineformsdependingonitste
mperaturehistoryinproduction
anduse.Thesizeofthefatcrystalsalsoaffectstheirfunctionality.Small
crystalshavealargersurfaceareare
lativetolargeonesandaremoreable
withinthecrystalmatrix.Thecrystal-
lineformofafatisnotusuallyassessedormeasuredeventhoughitmay
affectthefatperformance.
References

348.
Podmore,J.,1997.Bakingfats..In:Bent,A.J.(Ed.),TheTechnologyofCakeMaking.Blackie
AcademicandProfessional,London,UK,pp.25

47.
FIGURE2.4
Examplesofsolidfatindexprofiles.
78
BakingProblemsSolved
2.3.2Canyouexplainthedifferenttermsusedtodescribe
bakeryfats?Whatarethefunctionalitiesofthedifferentformsin
baking?
Chemically,allfatsandoilsconsis
tofatomsofcarbon(C)hydrogen(H)
andoxygen(O).Theyhavethesamebasicstructurewhichconsistsof
amoleculeofglycerolcombinedwith
uptothreefattyacids.Thebasic
nomenclatureismono-,di-andtri-gl
fattyacidsareattachedtotheglyce
rolmolecule.Thetermoilisused
todescribeafatinitsliquidform.Allfatsbecomeoilsifthetemperature
israisedhighenoughandalloilsbeco
mesolidfatifthetemperatureis
sufficientlyreduced.Thetermoil
ismostcommonlyusedforfatswhich
existasliquidsattemperaturesaround15

25

C.Fatsusedinbakery
practicearecommonlyamixtureofliq
uidandsolidfatcomponents,and
thismaybeexpressedasthemeltingp
rofileorSFIofthefatconcerned
(see
Section2.3.1
).
Fattyacidsareoneofthekeybuildingblocksofanimalandplanttissues.
Therearedifferentfattyacids,andtheirphysicalandchemicalformvaries
accordingtotheirchainlengthandabsence/presenceofcarbondoublebonds
(C
~
C)inthechain.Thesignificantimpactofthedifferentfattyacidsison
liquidatagiventemperature.
Thedegreeof
saturation
infatsdescribesthenumberofcarbondouble
bondswhicharepresent.Asthenumberofcarbondoublebondsincreases,
thedegreeofsaturationdecreasesandsodoesthemeltingpointofthe
fat;thedownwardsprogressionisfrom
saturated
to
monounsaturated
to
polyunsaturated
sothathighly
saturatedfattyacids
tendtobesolid.
Saturated
fatstendtobeverystableandhavealongshelf-life.Theyalso
tendtohavehighlyfunctionalrolesinthemanufactureofbakedproducts;
Cauvain,
2015
),aidairincorporationincakemaking(see
Section5.2
)andprovidelift
inlaminatedproducts(see
Section7.1.1
).However,theyalsotendtohavea
negativehealthimage.
Theproportionofthedifferentformsofsaturationvariesaccordingtothe
sourceoftheoil/fat.Today,therehasbeenasignificantmoveawayfrom
animalfatsinbakeryproducts(withthepossibleexceptionofbutter)to
However,thismeansthattheyarealsomainlyintheliquidformandsodo
nothavethebakingfunctionalityofthesolidfats.Themainexceptionis
palmoilwhichisabout50%
saturated
and40%
monounsaturated
fat.
Itispossibletomodifythephysicalandchemicalcharacteristicsofnatural
oils.Onemethodis
hydrogenation
inwhichtheoilisreactedwithhydrogen
gasathightemperaturesandpressure.Theprocessconverts
polyunsaturates
to
monounsaturates
andthento
saturates
andincreasesthefunctionalityof
RawMaterials
Chapter|2
79
thefatfordifferentbakingprocesses.Theprocessof
hydrogenation
produces
saturatedfatsbutnosignificantlevelsof
trans
fats.
However,
partialhydrogenation
whichhadbecomemorepopulardue
toconcernsovertheconsumptionofsaturatedfatsgeneratessignificant
levelsof
trans
partial
hydrogenation
producesdifferentlevelsof
trans
fatsfromdifferenttypesof
fat.The
trans
formoffatexistsbecausetherearetwophysicalwaysforafat
toformwiththesamecombinationofCHOatoms;the
trans
isoneformand
theotherisknownasthe
cis
form.
Trans
fatsdooccurinnatureandare
presentinproductssuchasbutter,milkandeggs.
Therearealternativewaysto
hydrogenation
forprovidingbakingfats
withthefunctionalitynecessaryforbaking.Oilsfromnaturalsources,for
example,palmoilasdiscussedabove,areamixtureofsolidandliquid
fractionsandsothephysicalseparationofthedifferentfractionscanbeused
topreparearangeofdifferentfatswithspecificfunctionalproperties.Using
thistechnique,itispossibletopreparestearineoilfractionswithmelting
pointsofupto60

C.Theprocessisreferredtoas
fractionation
andhasalso
processingathighertemperatures.
Interesterification
involvesenzyme(lipase)-assistedmodificationofthe
oilorfatcomposition.Anyoilorfatcombinationcanbe
interesterified
.
Solidfatsmayexistinanumberofcrystallineformsdependingonhow
theyhavebeenpreparedincommercialpractice.Itislargelythecooling
changeduringsubsequentstorage.Itissaidthatfatsexhibit
polymorphism
,
andthethreecrystallineformsaredenotedas

,

0
and

.The

crystals
havethelowestmeltingpointandaresmall,unstablecrystals.Thetransition
isfrom

to

0
andthento

;thelatterformtendstobethelargestcrystals
andhavethehighestmeltingpoints.Thecrystallineformsofthefatshave
beenlinkedwiththeirfunctionalityinbaking(e.g.,
Cauvain,2001
).
References
Cauvain,S.P.,2001.Theproductionoflaminatedproducts.CCFRAReviewNo.25.Campden
BRI,ChippingCampden,UK.
Cauvain,S.P.,2015.TechnologyofBreadmaking,thirded.SpringerPublishingInternational
AG,Switzerland.
Furtherreading
Stauffer,F.E.,1993.Fatsandfatreplacers.In:Kamel,B.S.,Stauffer,C.E.(Eds.),Advancesin
BakingTechnology.BlackieAcademicandProfessional,Glasgow,UK,pp.336

370.
80
BakingProblemsSolved
2.3.3Ourbreaddoughsprovesatisfactorilybuttheydonotrise
intheoven.Onsomeoccasions,theymayevencollapseand
blistersformonthedoughsurfaceinthecornersofthepans.
Whatisthecauseoftheseproblems?
Alackofovenspringorcollapseofthedoughpieceintheovenusually
differentreasonsbutyourcommentontheformationofblistersonthedough
surfaceinthecornerofthepansstronglysuggeststhatyourproblemcomes
fromalackfatorothersuitablelipid(e.g.,emulsifier)inyourimproveror
breadformulation.Theproblemcanbetoolowaleveloraninappropriate
characterofthefat.
Inmodern,no-timebreadmakingsystems,e.g.,theChorleywoodbread
process(CBP),theadditionofafatoremulsifierisimportantinensuring
CauvainandYoung,2006
).Ithasbeen
knownforquitesometimethatitisonlythesolidportionofthefatwhich
importantthataproportionofanyaddedfatshouldremainassolidinthe
doughattheendoffinalproof.Astypicallyfinalproofiscarriedoutat
around40

45

C,thisrequiresthatthefinalmeltingpointofthefattobe
above45

C.
Thenecessarylevelofsolidfattoachievetherequiredeffectat45

Ccanbe
quitesmall,andvaluesaslowas0.02%flourweighthavebeenquoted.
However,itisknownthattheminimumleveloffatrequiredvarieswithflours.
Ingeneral,higherlevelsoffatappeartoberequiredwithstrongerwhiteflours
andageneralrecommendationof0.7%ofacompoundbakeryshorteningwas
ficientlyhighlevelofsolidfatremainedinthedoughattheendofproof.
erablyhigherlevelsofaddedfatthanwhiteflours.
Cauvain(2015)
provides
anexampleforwholemealbreadmadebytheCBPwheremaximumbread
volumewasobtainedwhenaddedfatlevelsreached4%oftheflourweight.
storageofflourcanbecompensatedwiththeadditionofhighlevelsofa
suitablefat.
doughbyhelpingtocontrolgasbubblesizeandstability.Compositebakery
shorteningsareamixtureofoilandsolidfatatdoughtemperatures,butit
isonlythesolidfatportionthatcanplaythenecessarygasbubblestabilis-
ingrole.Themoleculesofthesolidfatportionalignthemselvesattheinter-
faceofthegasbubbleandtheliquiddoughphaseandplayapartin
peraturerisesinthedoughsomeofthefatmoleculesmeltandlosetheir
abilitytostabilisethegasbubbles.Eventually,allofthefatmeltsandother
RawMaterials
Chapter|2
81
materials,principallythegluten,arelefttomaintaingasbubblestability.
Akeyroleforfatmaybethepreventionofcoalescenceofgasbubblesin
thedoughintheearlystagesofbaking.
Emulsifiersarecommonlyusedtoreplacefatinbreaddoughsonthe
basisthattheycanbeusedatlowerlevels.Insimplisticterms,theymaybe
consideredasspecialisedfatswithahighmeltingpoint.Theyplayasimilar
roletofatsinstabilisinggasbubblesinthedough.However,theirmelting
profileisquitedifferentfromthatoffatsinthattheyremainsolidtomuch
highertemperaturesinthedough,typicallyaround60

C.Morerecently,
theadditionoflipaseenzymes(
Cauvain,2015
)hasbeenconsideredtoplay
aroleinconferringgasbubblestability.
Theblistersthatyouobserveonthedougharegasbubbleswhichhave
becomeexcessivelyexpandedandareunstable.Whenthedoughreaches
expansion,andindividualbubblesbecomeover-expanded,perforateand
collapse.Collectively,theyleadtototaldoughcollapse.Theadditionofa
suitablelevelofahighmeltingpointfatoremulsifiershouldovercomethis
problem.
References
Cauvain,S.P.,2015.TechnologyofBreadmaking,thirded.SpringerPublishingInternational
AG,Switzerland.
Cauvain,S.P.,Young,L.S.,2006.TheChorleywoodBreadProcess.WoodheadPublishingLtd,
Cambridge,UK.
82
BakingProblemsSolved
2.3.4Whatistheroleoffatinthemanufactureofpuffpastry?
Inthemanufactureofpuffpastry,fatmaybeaddedtothepasteintwo
twoadjacentdoughslayers.Thelatterisbyfarthemoreimportantofthe
twousesandcontributesmosttotheformationofthecharacteristiclayered
structureandflakyeatingcharacter.
expansionofthestructureoccursasthedoughlayersareforcedapartduring
baking.Thepressurefortheexpansioncomesfromthewaterpresentin
thedoughlayersasitturnstosteam.Asthesteamtriestoescapetothe
atmosphere,themeltingfatactsasabarriertoitsprogressandthedough
layersmoveapart(
CauvainandYoung,2008
).
Toobtainmaximumpastrylift,itisimportantthatthefatlayersremain
carefulattentionshouldbepaidtotheprocessingtemperatureforthepaste.
Forexample,butterhasalowSFIat20

Candpastesmadewithallbutter
benefitfromprocessingattemperaturesaround12

14

Cwhichgiveswork-
ablefatlayersbutoneswhichwillnotbesobrittleastobreakduring
Astheaerationmechanisminvolvesthefat,itisreasonabletoassume
thatthecharacteristicsofthefatplayapartinthedegreeofliftduring
bakingwithliftdependingonthefollowingcharacteristics:

Thelevelofaddedfat,withhigherfatlevelsgivinggreaterlift.

TheSFI,withhigherSFIgivinggreaterlift.

Thefirmnessofthefatatpointofuse,withgreaterfirmnessgiving
greaterlift.

Thecrystallineform,withsmallercrystalsizegivinggreaterlift.
AlthoughpastryliftbenefitsfromahigherSFI,theremaybesomeloss
ofeatingqualitiesasfatswithveryhighmeltingpointstendtogiveagreasy
Theadditionoffattothebasedoughhasasmalladverseeffectonpastry
liftandgivesamoretendereatingqualitytothefinalproduct.
Theimpedanceofsteambythefatlayersalsoplaysapartinthe
aerationofDanishpastriesandcroissant,thoughinthesecases,liftis
affectedbytheactivityoftheyeastw
hichcontributestotheexpansionof
thedoughlayers.
Reference
Cauvain,S.P.,Young,L.S.,2008.BakeryFoodManufactureandQuality:WaterControland
Effects,seconded.BlackwellScience,Oxford,UK.
RawMaterials
Chapter|2
83
2.3.5Ourpuffpastryfailstorisesufficientlyeventhoughwe
believethatweareusingthecorrectleveloffat.Areweusing
thecorrecttypeoffat?
Theliftinlaminatedproductscanbeaffectedbytwopropertiesofthe
laminatingfat;theSFIandthesizeofthecrystalsinthesolidfatportion.
Thelaminatingfatplaysasignificantroleintheaerationmechanismin
puffpastrybyimpedingthemovementofsteamfromthedoughlayersto
thesurroundingatmosphere(see
Section7.1
).Solidfatlayersformagreater
barrierthanliquidonesandsotheproportionoflaminatingfatwhich
remainssolidasthepastrybeginstobakeisanimportantcharacteristic.
Asdiscussedabove,wecanmeasurethesolidfattoliquidoilratioina
givenfatusinganumberoftechniques,forexampleNMR.Foragiven
temperature,theratioisdescribedasthe
SFI
withthevaluegivenbeingthe
solidfatportioninthemixture.Suchmeasurementsaretypicallymadeat
threeoffourdifferenttemperaturestoestablishthesolidfatprofile.
ThehighertheSFI,thegreaterthepuffpastryliftwillbe(see
Fig.2.5
),but
theincreaseinsolidfatmayleadtoanunacceptablechangeineatingcharac-
teristics.Itisparticularlyimportantthattheproportionofsolidfatat40

Cis
restrictedbecauseitdoesnotmeltinthemouthandconfersanunpleasant
waxyeatingqualitycommonlydescribedaspalatecling.Wesuggestthatany
laminatingfatyouuseshouldnothavemorethan5%solidfatat40

C.
Thestorageandprocessingtemperaturesusedalsoaffecttheperformanceof
thelaminatingfat,soitisimportanttoavoidunnecessarywarmingandcooling
ofthestocksoffat.Thetemperatureatwhichthepastrymanufacturingprocess
iscarriedoutcanalsoaffectliftanditisbestprocessthepastryatatemperature
whichislowerthanthemeltingpointofthefat.
Ifyouareworksofteningthefatbymeansofpumpingorextrusionthen
youmaynoticesomechangesinperformance,soitisimportanttokeepand
anyworksofteningactivitiesasconstantaspossible.
Furtherreading
Cauvain,S.P.,2001.Theproductionoflaminatedproducts.CCFRAReviewNo.25.Campden-BRI,
ChippingCampden,UK.
FIGURE2.5
Effectoflarge(left)andsmall(right)fatcrystalsonpuffpastryheight.
84
BakingProblemsSolved
2.3.6Whatistheroleoffatincakemaking?
Themainfunctionoffatincakemakingisassistwiththeincorporationofair
intothebatterduringmixing.Italsoaffectstheairbubblesizeinthebatter
andbubblestabilitybeforeandduringtheearlystagesofbaking.
Cakebattersareessentiallyafoam,thatisasysteminwhichairbubbles
aretrappedandheldinanaqueousphase.Foamsystemsarecharacterisedby
thefactthatalltheairbubblesareseparatedfromoneanotherbyathinfilm
ofstabilisingmaterial.Duringbaking,thefoamchangestoasponge(inthe
genericsense),thatisasysteminwhichalloftheaircellsareinterconnected
andvapoursandliquidscanmovethroughthematrix.Themomentatwhich
thefoaminacakebattermakestheconversiontoaspongehasmuchtodo
withtherecipeformulationandthestabilityoftheairbubbleswhilethetem-
peratureisrisingmakesamajorcontributiontofinalcakevolume.
Theprotectivefilmwhichformsaroundthegasbubblesmaycomefrom
anumberofsources.Solidfatcrystalscancontributetotheprotectivefilms
inthebatterfoam,andtheyaretypicallylocatedattheinterfacialfilm
ofthefatincakemaking.Ofthethreefatpolymorphscommonlyencoun-
tered,thevolumeofairwhichcanbeincorporatedintothebatterisgreatest
withthe

0
,lesswiththe

andleastwiththe

form.
Asthebattertemperaturerisesintheoven,thesolidfatturnstoliquidoil
andthenaturalbuoyancyoftheairbubblescausesthemtotryandmove
upwardstoescape.Thelongerthebubblesareretainedinthebatterthegreater
thecakevolumewillbe.Thisrequiresthatthefathasahighmeltingpoint.
However,dispersionofthesolidfatcrystalsisimportantiftheyaretobeeffec-
tiveandaliquidoilcomponentisnecessarytoachievethatreadydispersion.
Fatsandoilscontributetothesoftandtendereatingpropertieswhich
arerequiredforcakes.Inpart,thisbenefitcomesfromtheeffectonbatter
aerationandinpartfromthelubricatingeffectthatfathasinthemouth.
Furtherreading
Cauvain,S.P.,Young,L.S.,2006.BakedProducts:Science,TechnologyandPractice.Wiley-
Blackwell,Oxford,UK.
RawMaterials
Chapter|2
85
2.3.7Wearemakingall-buttercakesbutfindthatafterbaking
theylackvolumeandhaveafirmeatingcharacter.Whyisthis
andisthereanywaytoimprovethecakequality?
Butterisoftenchosenincakemakingduetoitsqualityattributesrelatedto
tionwithnaturalnessandquality.However,beinganaturalproduct,it
canbethesubjectofnaturalqualityvariationsandhascharacteristicswhich
arenotalwaysbestsuitedtocakemaking.
Butterisamixtureofbutteroils,waterandoftensalt.Commonly,
thelevelofwatermustnotexceedafixedvalue(16%intheUnited
Kingdom)andsaltlevelsmayalsobefixed.Thus,ifbutterisusedto
replaceanoilorbakeryshortening
,thenthelevelofadditionshould
beincreasedtoabout1.2timestherecipeshorteninglevel.Aweightfor
weightreplacementofshorteningw
ithbutterwillthereforeresultin
alowerfatlevelintherecipewhichwillreducebatteraerationand
cakevolume.Butteroilsandbutterfatsareavailablewhichcanbeused
onaoneforonereplacementbasis
becausetheydonotcontainwater
(
Rajah,1997
).
Generally,theabilityofbuttertocontributetobatteraeration,andthus,
cakevolumeisinferiortobakeryshorteningsorcakemargarine.Thisis
becausetheSFIat20

Cforbutterislowerthanthatgenerallyrecommended
foruseincakemaking,typically,around24%ofafatshouldbesolid
at20

C.ButterSFIsat20

Cvaryaccordingtotheirsource,inpartdueto
differencesandchangesinthefeedinghabitsofthecows.
Thetemperingofbuttercanimproveitsfunctionalityincakemaking.
Wesuggestthatyouholdthebutterat28

30

Cfor18

20hbeforeuse.
Thistemperingperiodpermitsabeneficialincreaseinthecrystalsizeofthe
solidfractionsinthebutter.Youshouldensurethatfullequilibrationoftem-
peraturehastakenplacebecauseoftentheslabsofbuttermaybestoredona
thecentreofthestack.
Considerableimprovementsincakevolume,softnessandeatingquality
canbeobtainedbyaddingalowlevelofglycerolmonostearate(GMS)to
thebatter.TheGMSismoreeffectivethanthebutteratstabilisingthefoam
structureofacakebatter.Wesuggesttheadditionofalevelof1%(GMS
solids)ofthetotalbatterweight.TheGMSshouldbeinthe
alpha
form
andmaybeaddedasastabilisedgel.
Reference
Rajah,K.K.,1997.Cream,butterandmilkfatproducts.In:Bent,A.J.(Ed.),TheTechnology
ofCakeMaking.BlackieAcademicandProfessional,London,UK,pp.48

80.
86
BakingProblemsSolved
2.3.8Wehavebeenusingoilintheproductionofoursponge
cakes,butwewishtochangetousingbutter.Canyouadviseon
howtodothis?
Therearetwocoursesofactionopentoyou;eithermeltthebutterandaddit
asawarmoiloradditinthesolidform.
Thepracticeofmeltingfatstoincorporatethemintospongebattershas
beenknownforquitesometime.Thetraditionalbutterspongeutilisesa
basicspongerecipetowhichthemeltedbutterisaddedafteralloftheother
ingredientsattheveryendofthemixingprocess.Thebuttershouldonlybe
heateduntilitisjustliquid;otherwise,thehotoilmayincreasethebatter
temperaturehighenoughtocauseaprematurereactionofthebakingpowder.
Youmayfindsomebenefitinusingalittlemorebakingpowderinthe
formulationtocompensateforanylosseswhichmayoccur.Ifyouarenot
alreadydoingsoyoumayfindsomeadvantageintheadditionofa
suitableemulsifiertotheformulation.
Ifyouaregoingtousethebutterinthesolidform,wecertainlyrecom-
mendtheadditionofanemulsifiertotheformulation;otherwise,youwill
notachievetheproductvolumethatyouareseeking.Youmayexperience
Chapter|2
2.3.9Wewishtoproduceasoftereatingspongecakeandhave
seeking.Istheadditionoffattospongebatterspossibleandwhat
doweneedtodotoachievethequalityweareseeking?
Inatraditionalspongerecipecomposedofflour,sugarandegg,themixing
actionofthewhiskdrawssmallairbubblesintothebatterduringmixing.
Theeggproteins,principallythelipoproteins,alignthemselvesattheinter-
faceoftheairbubbleswiththeaqueousphase.Attheinterface,theyprovide
stabilitytotheairbubblesandpreventthemfromrisingtothebattersurface
andescapingtotheatmosphere.
Thisbubblestabilisationofthebatterfoamisparticularlyimportantin
theearlystagesofbakingwhentheincreaseintemperatureincreasestheten-
dencyoftheairbubblestorise.Laterduringbaking,thesolidpartofthe
leavingbehindaspongestructure(here,thetermspongeisusedinthe
genericsensereferringtoastructureinwhichtheindividualcellsareinter-
connectedandgasesandliquidsmaydiffusethroughthematrix).
Whenoilsorsolidfatsareaddedtoatraditionalspongebatter,theyinhibit
theinclusionofairintothebatteranddisplacetheeggproteinsatthegasbub-
ble/aqueousphaseinterface.Thischangeallowsmanyisgasbubblestoescape
fromthebatter,especiallyduringbakingwhenanysolidfatisturningtoliquid
oil.Theresultisthatthemechanicalaerationismuchreducedandtheresul-
ducingspongecakesencouragethescaldingofthemixingbowltoremove
anytracesoffatbeforethestartofmixing.
Oilsorfatsmaybeaddedtospongecakestoimprovetheeatingquality
bycarefullyblendingthemintothebattertowardstheendofbaking.Inthe
caseoffatswhicharesolidatbakerytemperature,itisadvisabletoheat
thefatuntilitisliquid.
Alternatively,youcanaddanemulsifier,suchasGMStothesponge
formulationtotakeoverthemainairbubblestabilisingrolefromtheegg
proteins.Thelevelofadditionneedstobesufficientlyhightoensurethat
bubblestabilityismaintainedduringbakinguptothepointofconversion
fromfoamtosponge.Oilsaremoresuitablefortheproductionofenriched
spongesthoughtheadditionofsolidfatispossible,spongecakevolumeand
texturearelesssatisfactory.
Furtherreading
Cauvain,S.P.,Cyster,J.A.,1996.Spongecaketechnology.CCFRAReviewNo.2.Campden
BRI,ChippingCampden,UK.
88
BakingProblemsSolved
2.3.10Wewanttomakearangeofbakeryproductsusing
butterasthemainoronlyfatintherecipe.Canyouadviseusof
anyspecialtechnicalissuesthatweneedtotakeintowhenusing
butter?
Thecompositionofbutterisusuallyfixedbylocalregulations.Itisan
emulsionofwater-in-oilandtypicallycontainsmorethan80%fat,lessthan
2%milksolidsandlessthan16%water.Despitehavingafixedcomposition
itsperformanceinbakingcanvary.Thebestknownvariationcomeswith
thetwiceyearlychangeinthefeedingpatternsforcowsinmanypartsofthe
world(
Rajah,1997
).Withthechangeoffeedcomesmallbutimportant
changesintheunderlyingfattyacidcompositionandsolidfatcontentwhich
canaffectitsabilitytoincorporateairduringcreamingprocessesinthe
manufactureofbakedproducts(e.g.,cakesandbiscuits).
Buttercontainssignificantamountsofbutyricacid(alowmolecularweight
fattyacid)whichisvolatileandmakesasignificantcontributiontotheflavourof
thefat.Thereleaseoftracesofthisacidthroughtheprocessofhydrolysismakes
butterparticularlysusceptibletorancidity.Toavoidanypotentialproblems,the
butterwillbedeliveredchilledandshouldbestoredatthesametemperature,
typicallyaround4

6

C.Youshouldalwaysusethebutterwithinitsdesignated
shelf-lifeandwillfindithelpfultosetupastrictstockrotationsystem.
Thesolidfatcontentofbutteratdifferenttemperaturesisgivenin
Table2.1
.Thedatahighlightsomeofthetechnicalproblemswithusingbutter.
Asthesolidsfatcontentisveryhighatlowtemperatures,itcannotbeused
straightfromtherefrigeratorbutmusthaveitstemperatureraised,beforeitcan
beused.Thistemperingprocesstakestimeandrequirescarefulcontrolto
ensureuniformityofprocessingperformance(seealso
Section2.3.11
).
Achievingtheoptimumprocessingtemperatureswithbutterisvery
importantforitseffectiveuse.Forexamplesofrelevantprocessingtempera-
turesforlaminatedpastryproducts(see
Section7.1.17
).
Thesolidscontentofbutterislowerthannormallyconsideredsuitable
forcakemakingandthereisatendencyforall-buttercakestolackvolume.
Addingasuitableemulsifiertotherecipe(e.g.,GMS)commonlysolvesthe
problem(see
Section2.3.7
).
Reference
Rajah,K.K.,1997.Cream,butterandmilkproducts.In:Bent,A.J.(Ed.),TheTechnologyof
CakeMaking.BlackieAcademic&Professional,London,UK,pp.48

80.
TABLE2.1
TheSolidFatContentofButteratDifferentTemperatures
Temperature(

C)5101520253035
SolidFat(%)5348352417107
RawMaterials
Chapter|2
89
2.3.11Weareusingbutterinseveralofourbakeryproducts
whichcomesinchilledatabout4

C(ascartonsonpallets)and
areencounteringproblemswithv
ariabilityinitsprocessing.
Werecognisethatislikelytobeassociatedwiththe
temperatureofthebutterwhenweareusingit.Whatisthe
bestwaytotreatthebuttertogetamoreconsistent
performance?

Cand20

C,dependingonthe
product.Inthemanufactureofcakebattersandcreams,thebutterplaysa
majorroleinthenecessaryairincorporationandsomustbesufficientlyplas-
ticatthetimeofmixing;temperaturesatthehigherendoftheaboverange
aremostsuitableinsuchcases.Forpastrymaking,temperaturestowardsthe
lowerendoftherangemaybeusedbutasignificantdegreeofplasticityis
stillrequired(see
Section7.1.17
).
Asyourbutterisarrivinginthechilledformyouwillneedtoraiseits
temperaturebyquiteafewdegreesbef
oreitisinitsoptimumtemperature
range.Thebestwaytoraisethebutt
ertemperatureistostoreitinwarm

Cand25

C(no
morethan30

C),buttoobtainconsistentperformance,itiscrucialthatthe
temperatureofthewholecartonreachesthesetemperatures.Toachieve
this,youwillneedtomakesurethatth
ereissufficientaircirculation
aroundeachcartonandthatyouallowsufficienttimeforequilibrationof
thecartontemperaturetooccur.Thewholeprocesscantakeseveraldays,
andwesuggestthatyouallowatleast4

8daysequilibrationbefore
tryingtousethebutter.
Donotbetemptedtousehighairtemperaturestospeed-uptheprocess
asthiscanleadtosignificantoilingonthesurfacesofthebutterinthe
cartonsandlossoffunctionality.Butterwhichhasoiledandthencooled
endsupwithadifferent(larger)crystalstructurewhichmakesitunsuitable
forthemanufactureofmostbakeryproducts.
Radio-frequencyheatingandmicrowavehavebeensuggestedandused
fortemperingbutter.Thiscanreduce,butnotreplace,thestoragetime.
Onceagainoilingofthebuttershouldbeavoided.
Inthemanufacturingprocess,thebuttermaywellbepumpedorextruded
beforeuse.Themechanicalactionthattheseprocessesinvolvehelpin
achievingamoreuniformtemperaturedistributionthroughoutthefatbut
shouldnotbeusedtotryandreplacesoundtemperingprocedures.
90
BakingProblemsSolved
2.3.12Weareseekingtoreducetheleveloffatthatweusein
someofourcakerecipesbutfindthatsimplytakingfatout
adverselychangesourproductquality.Whatarethepossibilities
ofusingfatreplacerstohelpuswithourstrategy?
Therearetwokeyrolesforfatsincakemaking;oneistohelpwiththesoft
andtendereatingqualitiesthatweassociatewithcakesandtheothertohelp
withfoampromotionandbubblestabilityinthebatter(see
Section2.3.6
).If
youaregoingtoreducefatlevelsinyourrecipe,youwillneedtotakeboth
intoaccountandthiscanleadtoconflictingresults.Youmayalsoexperi-
encesomelossofflavourfromyourproduct.
Atypicaleffectofsimplyreducingfatlevelinyourrecipewithout
makinganyrecipechangesisillustratedin
Fig.2.6
.Theproducthasalower
volume,densercrumbandfirmereatingqualitieswhichareoftenquickly
Youcanovercomethelossoffoamcreationandbubblestabilitywhen
youreducefatlevelthroughtheadditionofasuitableemulsifiersuchas
GMS.However,youwillfindthatthecakeeatingqualitiesmaybecomea
littlefirmer.Youmayfindsomeadvantageinreducingtheegglevelinyour
recipe(andadjustingwateraccordingly),butyouneedtobecautiousaslow
levelsofeggsolidscanresultinincreasingfragilityofcakecrumbandeven
theformationofunwantedcracksduetotheloweringofproteinlevels.If
thisdoeshappenthenyoucouldraisetheproteincontentoftheflour.
Thereareclaimsforawiderangeoffatreplacers,butitisworthbearing
inmindthatnoneofthemdeliversexactlythesamequalitiesasfatandthat
theiruseinareduced-fatcakerecipewillalwaysneedotherrecipechanges
toproduceasatisfactorycakeproduct.Inabroaderaspect,fatreplacers
canbeplacedinoneofthreecategories;carbohydrate-based,protein-based
andfat/lipidanalogues.Asignificantnumberofthefatreplacersareaimed
atreducingthecalorificvalueofthefinalproductandsoweightforweight
theydeliversignificantlyfewercaloriesthanfat.
Inmanycases,thecarbohydrate-basedfatreplacersarecomposedof
fibrousmaterialsandsorequiretheadditionofextrawatertotherecipeto
FIGURE2.6
Effectofloweringfatlevelincakes;left,s
tandardrecipeandright,reducedfatrecipe.
RawMaterials
Chapter|2
91
maintainasufficientlyfluidbatterforprocessing.Itismainlythepresence
oftheextrawaterthatdeliversthefat-mimickingpropertiesofthematerial,
buttheextrarecipewatercanleadtounbalancingofotherrecipecompo-
nentsandwillresultinahighermoisturecontentinthefinalproduct.
Unfortunately,althoughthefatreplacermayholdthewaterinthebatterin
mostcases,itdoesnotsufficientlybindwaterinthebakedproductwiththe
resultthattheproductismoresusceptibletomouldgrowth.Similarissues
applytotheprotein-basedfatreplacers.
Thepositionwithfat/lipidanalogue
sisslightlydifferentassuchingre-
dientsdotendtomorecloselymimicthelubricanteffectoffatwith
respecttocakeeatingquality.Howeve
r,thesematerialsstilllackthefoam
promotionandbubblestabilisatio
npropertiesoffatandsocommonly
recipesincorporatingthemre
quiretheuseofanemulsifier.
Ifyouarethinkingofusinganyoftheavailablefatreplacers,itwouldbe
advisabletocheckonwhethertheyarepermittedincakesandwhat,ifany
specialingredientsdeclarationsneedtobemade.
BakingProblemsSolved
2.4.1Whattypeofsugar(sucrose)shouldweuseforthe
differentproductsthatwemakeinourbakery?
Sugar(sucrose)hasanumberofdifferentfunctionsinbakedproducts;in
impactontheformationofproductstructureswhich,inturninfluences
texture,eatingqualitiesandshelf-life,bothsensoryandmicrobial(
Cauvain
andYoung,2008
).
Sucroseisavailableinanumberofcrystallineandliquidforms(various
typesofsyrups).Insummary,themainformsofsucrosethatareusedinthe
manufactureofbakedgoodsare:

Granulated

Usually,thecoarsestcrystalline,refinedwhiteform.

Caster

Smallercrystalsseparatedfromthepreparationofthegranulated
form.

Pulverised

Maybemanufacturedbyregrindingacrystallineform.

Icingsugar

Afine,powderedsugarobtainedbygrindingcrystals.

Demerara

Alightbrown,crystallinesugarwithpigmentsderivedfrom
thenaturalsugarcane.

Softbrown

Amixtureofsmallcrystallinesugarandmolasses.

Molasses

Adark-colouredsyrup,theresidueofthesugarcane-refining
process.
Manyofthefunctionsofsugarinbakedproductsrequirethatitshould
beinsolutioninthemix.Thisdoesnotnecessarilymeanthatyouhaveto
prepareasugarsolutioninthebakery.Sugarhasahighsolubility(typically
sucrosedissolvesinhalfitsweightofwaterat20

C),butthequantitythat
therateatwhichtheydissolveandinlowwatersystems(e.g.,biscuit
dough),thiscanbeacriticalfactorindecidingwhichformtouse.
Someofthekeyrequirementsforsugarpropertiesaresummarisedforthe
differentbakedproductgroupsbelow.

Bread
Levelsofsugaradditionmayrangefromzerotoasmuchas20%offlour
weightintherecipeinthemanufactureofbreadsaroundtheworld.The
waterlevelsarerelativelyhighanddoughprocessingtimesfrommixto
ovenarerelativelylongbycomparisonwithotherbakedproducts,and
usually,thereissufficienttimeisavailableforanyaddedsugartoreadily
dissolve.Thismeansthatmostofthecrystallineformscanbeusedwith-
outcreatinganyspecificproblems.

Fermentedproducts(
e.g.,
rollsandbuns)
Sugariscommonlyaddedtorolls,bunsandothersimilarfermentedpro-
RawMaterials
Chapter|2
93
additionstilltendtobelowenoughtoallowfortheuseofallthecrystal-
lineforms.Youshouldnotethathighlevelofaddedsugarcanhavean
inhibitoryeffectonyeastactivity.

Spongesandcakes
Castersugaristheformmostcommonlyusedinthemanufactureof
spongesandcakes.Whilegranulatedsugarwillreadilydissolvein
thewaterpresentinspongeandcakebatters,therecanbeproblemswith
recystallisationonthesurfaceofthebakedproduct.Acommonphenome-
nonwhensugarrecystallisationoccursistheformationofsmallwhite
spotsonthecrust(see
Section5.19
),andinlessextremecases,thebrown
crustcolourmaybetingedwithagreyhazearisingfrommanysugarcrys-
talstoosmalltobeseenwiththenakedeye.Acrystallineformofsugaris
preferredformanycakemixingproceduresasithelpswiththedispersion
oftherecipefatandtheincorporationofairintothemix(see
Section5.2
).

Fruitedcakes
Incakes,whereahighproportionofdriedfruitisaddedtothemix(e.g.,
celebrationcakes),ithasbecometraditionaltouseaproportionofbrown
sugarsandsyrupstoaddtothecolourandflavourprofileofthebaked
product.

Biscuitsandcookies
Commonly,thefinergradesofsugar,e.g.,pulverised,areusedinthe
manufactureofbiscuitsandcookies.Thisisbecausetheaddedwater
levelsarerelativelylow,sothereisasignificantpotentialforsugar
recrystallisationofthesurfaceoftheproducts.Insomebiscuits,brown
sugarsorsyrupsmaybeaddedtoconfercolourandflavour.

Pastries
Casterorpulverisedsugarisusuallypreferredforthemanufactureofpas-
triestoavoidsugarspottingonthesurfaceofthebakedpastries.

Otherbakeryproducts
Icings,toppingsandfillingsoftenuseaproportionofthefinestsugar
grades,e.g.,icingsugar.
Ifyouarenotabletoaccessorstorearangeofsugartypes,youmay
havetoconsidermodifyingyourmixingprocedures.Forexample,withthe
coarsergrades,youmayhavetodissolvethesugarintherecipewaterbefore
addingittotheotheringredients.Ifthesugarlevelsinyourproductarehigh
withrespecttothewaterlevels,youmaystillhaveproblemswith
recrystallisation.
Furtherreading
Cauvain,S.P.,Young,L.S.,2006.BakedProducts:Science,TechnologyandPractice.Blackwell
Publishing,Oxford,UK.
Cauvain,S.P.,Young,L.S.,2008.BakeryFoodManufactureandQuality:WaterControland
Effects,seconded.WileyBlackwell,Oxford,UK.
94
BakingProblemsSolved
2.4.2Canyouexplainsomeofthemainfeaturesofalternative
sugarstosucrose,andhowtheymightbeusedinbaking?
Thesugarswhichareusedinbakingfallintotwomaingroupsclassedas
sugarsbecausetheyconsistofoneglucosemoleculewhilethedisaccharides
comprisetwoglucosemoleculesindifferentconfigurations.
sugarswhichmaybeusedinbaking;importantonesarerelatedtothe
impactonthegelatinisationcharact
eristicsofwheatstarchandtherefore
productstructure,theirimpactso
nproductwateractivityandinturn
productshelf-life,andthe
Table2.2
).Allsugars
contributetotheMaillardbrowningreactionwhichformsthecrustcolour
ofbakedproducts.
Themainmonosaccharidesarefructoseandglucosebothofwhichoccur
naturallyinfruits.Fructoseisanisomerofglucose(thatisaglucosemole-
culewithadifferentarrangementofthesameatomsinthemolecule)which
canbeobtainedinthecrystallineandliquidforms.Itisasugarwhichis
digestivesystemdoesnotrequireinsulin.Fructosemaybeusedinasyrup
form(highfructosecornsyrup,mainlyamixtureoffructoseanddextrose)
whichisreadilyfermentablebyyeast.
Glucosemaybeusedasapowder(dextrosemonohydrate)orasasyrup
(containingabout20%)waterwithdifferentamountsofdextrose.Theper-
centageofreducingsugarsinthesyrupisgivenbyitsdextroseequivalent.
Glucosesyrupsarefoundmainlyinjamsandfondantsthoughtheymayfind
useincakeandbiscuitmaking.Dextrosesolidsareoftenusedtoextendthe
mould-freeshelf-lifeofcakes,buttheirlevelofadditionmaybelimitedby
thebrowningreactionwhichoccurs.
TABLE2.2
Sucrose1.0
Fructose1.7
Maltose0.35
Lactose0.27
Glucosesyrup0.30
RawMaterials
Chapter|2
95
Themaindisaccaharides(inadditiontosucrose)aremaltoseandlactose.
Maltosefindsitswayintobakedgoodsusuallyaspartofmaltedwheat
orbarleyproductsandfindsuseinbreadandotherfermentedgoods.Itis
commonlyavailableintheformofasyrupwithalowdegreeofbrowning.
Initspurer,crystallineform,maltosehasbeenusedtoslowdownstarch
2.4.3Whyaresugarsaddedtosomebreadrecipesbutnot
others?
Astheflavouroffermentedproductsisverypersonalthing,therearewide
variationsinthetypesofsugarsaddedandthelevelsofadditionused.When
recipesarecomparedaroundtheworld,itiscommonlyobservedthatpan
andhearthbreadsinnorthernandwesternEuropehavenoaddedsugar,in
MediterraneanEurope,theMiddleEastandtheAmericaslowormodest
levelswillbepresent,whereasinAsialevels,ittendstobethehighest.
Sugarlevelsinallpartsoftheworldtendtobehigherinbunsandrolls
ofsugarsusedaresucrose,dextroseandhighfructosecornsyrup.Eachof
solidsbasis(see
Section2.4.2
).
Acommonperceptionisthatsugarsareaddedtosupportfermentation.It
iscertainlytruethatyeastwillbreakdownsugarsduringthefermentation
processtoyieldcarbondioxideandalcohol.However,thefermentationof
sugarsbybakersyeastisacomplexprocesswhichdependsmainlyonthe
availabilityofasubstrate(yeastfood),fermentationtimeandtemperature.
Bakersyeastmaybedescribedasafussyfeeder,inthat,itdoesnotuse
allsugarsourcesatthesametime,thoughitssuiteofenzymesisperfectly
abletodealwithbothmonoanddisaccharides.
Mostwheatflourscontainlowlevelsoffermentablesugars,typically
around1%comprisingfructose,glucoseandsucrose.Theactionof
alpha
and
amylasesondamagedstarchresultsinthegenerationofmaltose
duringfermentation,andthiscanalsobeusedbytheyeast.
Thekeyelementofyeastactivityisthatitutilisesreadilythemonosac-
charidesfortheproductionofcarbondioxidebutagroupofenzymes
commonlyheldinthedoublecellwallo
fyeastandcommonlyreferred
toasinvertaseisrequiredtobreak
downdisaccharideslikesucroseto
monosaccharidesbeforetheycanbeused.Inshortoforno-timedough
systems,theremaybeinsufficientti
mefortheyeasttoconvertsufficient
sucrose,andsointermsofgasproduc
tion,thepresenceofsuchsugarsis
largelyirrelevant.
Yeastactivityindoughisprofoundlyaffectedbyaprocessreferredto
asosmoticpressure(see
Section11.12
).Thisconceptisrelatedtothecon-
centrationofsolublematerialsinthesolutioninwhichtheyeastcellsare
held,incontrastwiththeconcentrationofsolublesubstanceswiththeyeast
cell.Ifbothconcentrationsareequal,thentheyeastcellisnotstressedand
canfunctionnormally.Ontheotherhand,ifthetwoconcentrationsarenot
equal,thentherewillbeamovementofsolublematerialsthroughtheyeast
cellwallwhichstressesthecells.
RawMaterials
Chapter|2
97
Beingreadilysoluble,recipesugarsincreasetheconcentrationofsoluble
solidsinthedoughliquorsurroundingtheyeastcells,andthehighconcen-
trationcanactuallyinhibityeastactivityandgasproduction.Theeffectof
increasinglevelsofsucroseongasproductionduringproofisillustratedin
Fig.2.7
.Inthisexample,theinhibitoryeffectofsucroseongasproduction
inano-timedoughislinkedwiththeincreaseinprooftimerequiredto
deliverastandardpandoughheightpriortobaking.Inpractice,prooftimes
wouldnotbelengthenedtoaccommodatethelowerrateofgasproduction,
ratheryeastlevelswouldberaised.However,thisactionmaynotbeentirely
successfulbecausetheosmoticpressureeffectofhighsucroselevelswill
continuetohaveaninhibitoryeffectontheyeast.
0
10
20
30
40
50
60
0246810121416
Increase in proof time (min)
Level of sugar (% flour weight)
FIGURE2.7
Effectofsucroseongasproductionduringproof.
98
BakingProblemsSolved
2.5OTHERINGREDIENTS
2.5.1Thechocolatefondantonourcreameclairshasbeen
fallingoffthetopofthecasingandgathersonthetray
underneathasastickysyrup.Whatcausesthisandhowcanwe
preventit?
Thechocolatefondantcontainsundissolvedsugarparticleswhichtendto
makeithygroscopic,thatis,likelytoabsorbwater.Asmorewateristaken
upbythefondant,thenthefondantbecomesmoreliquidandlikelytoflow.
Ifyouareputtingthefondantontothecurvedtopofthee

clairshell,thenit
canreadilyflowdownthesides.
Thewaterwhichcausesthisproblemwillcomefromtheothercomponents
oftheeclair.Usually,thesourcewillbethecreamwhichhasaveryhigh
wateractivity(equilibriumrelativehumidity,ERH)andthemoisturereadily
diffusesthoughttheporousanddrychouxshell.Themoisturewhichgathers
attheshell-fondantinterfaceactslikealubricantandhelpsthefondantflow.
Thisisnotaneasyproblemtoeliminatebecauseofthediversenatureof
thethreecomponentsinthecompositeproduct.Somepointstoconsiderare:

Thefondantwillalwayscontainundissolvedsugarandthereforebe
hygroscopicproperties.However,thesemaybereducedtosomeextent
byreplacingsomeofthesucrosewithaglucosesyrup,adjustingthe
waterasnecessary.

Addingasmallquantityoffattothefondant,say5

6%.

LoweringtheERHofthecreamtoreducethedrivingforceformoisture
migration.Theoptionsmaybelimitedthoughsucroseorevenglycerol
additionsmayhelp.

Achangetoaslightlymorepermeablepackingmayhelpbyallowing
somelossofmoisturetotheexternalatmosphere,butbewarethatthis
mayleadtothewholeproductdryingouttooquickly.

Tryicingthebaseofthee

clairshellbecausethisisusuallyflatterinshape.

Lookcarefullyatthetrayinwhichyoustandtheeclairs.Ifthee

clair
doesnotstandlevelinthetray,thenthereisalwaysapotentialforthe
fondanttoflowundertheinfluenceofgravity.
Furtherreading
Cauvain,S.P.,Young,L.S.,2008.BakeryFoodManufacture&Quality:WaterControland
Effects,seconded.BlackwellScience,Oxford,UK.
RawMaterials
Chapter|2
99
2.5.2Whenwechangedoursupplyofbunspicewewereusing
inourHotCrossbuns,weexperiencedproblemswithslow
gassingintheproverandflowingofthebunsduringbaking.
Whatcanwedotoavoidtheseproblems?
Manyspiceshaveanadverseeffectonyeastandwillinhibitgasproduction.
Thehighertheconcentrationofthespicethegreaterwillbetheeffect.
Itappearsthatthechangefromonespicesupplytoanotherhasresultedinyou
inadvertentlyaddingamoreconcentratedformtothedough,thatis,
theequivalentofahigherspiceleveleventhoughtheweightofaddedspicehas
remainedconstant.Alternatively,thenewspiceformulationyouareusingmay
haveagreaterconcentrationofoneormorespiceswhichhaveasignificant
effectongasproduction.
2.5.3Wewishtousemilkpowderinourfermentedgoodsand
haveheardthatitisadvisabletouseaheat-treatedform.Can
youexplainwhythisisso?
Theuseoffullyheat-treatedmilkormilkpowderproductsisessentialifyou
aretoavoidlossesinproductvolume.Inthecaseofliquidmilktypical,heat
treatmentconditionswouldrequireraisingthetemperaturetoaround80

C
andholdingitatthattemperatureforsome30minutesbeforecoolingand
use.Ifdriedmilkpowdersaretobeused,itisimportantthattheyhavebeen
subjectedtoasimilartemperatureprofiletothatgivenabove.
Similarproblemswithlossofvolumecanoccurifinadequatelytreated
milkpowderisusedintheproductionofspongecakegoods.Onsome
occasions,acollapseofthecakestructureandtheformationofacore
(anareaofcoarsedark-colouredcellstructure)mayoccur.
Theadverseeffectsofinadequatelytreatedmilkarisebecausethe
globulinproteinsnormallypresenthavenotbeendenatured.Thenormal
pasteurisationprocessappliedtomilkdoesnotdenaturetheglobulinswhich
caninterferewiththestabilityofthegasbubblesintheprovingdoughor
bakingcake.
Thesuitabilityofamilkpowderforbakingcanbeassessedwithasmall-
scalebakingtestorbyemployingtheSwortfiguercloudtest(
Swortifguer,
1958
).Aclearorslightlycloudysolutionattheendofthetestindicatesthat
themilkpowderhasbeenadequatelytreated.
Reference
ofnonfatdrymilkhasreceivedpropertreatment?BakersDigestOctober,78
RawMaterials
Chapter|2
101
aboutreducingthelevelsthatweuse?
Salt(sodiumchloride)hasanumberofdifferentfunctionsinthemanufacture
ofbakeryproducts,someofwhicharep
roductspecific.Themostimmedi-
atelyrecognisedoneistocontributeto
theflavourprofileoftheproduct.
Salthasitsowncharacter
isticsandisconsideredasoneofthefivebasic
tastes(theothersaresweet,acid,bitterandtherecentlyadded,umami).
Inadditiontoitsowndistinctiveflavou
r,saltplaysasignificantrolein
enhancingother,oftenmoresubtle
,flavours.Reductionsinaddedsalt
sowerecommendthatyoumakesmallbutprogressivereductionsover
aperiodoftimesothatthepalateofyourcustomersbecomeseducated
forlowersaltlevels.
Sodiumchlorideisoneofveryfewchemicalswhichconferasalty
flavour,anditisnoteasytoreplacetheflavourcontributionwithother
ingredients.Potassiumchloridemaybeusedtoreplacethesodiumsalt,but
asthelevelofpotassiumchlorideincreases,thereisadevelopmentofan
unacceptablelevelofbitternessintheproduct.Eachofthesaltreplacers
whichareofferedhasadistinctiveflavourprofilebutallaredifferentfrom
sodiumchloride.Otherflavoursenhancersareofferedforuseinlowersalt
foods,buttheirsuitabilityforusedependsonthefoodinwhichtheyareto
beused.Inbreadmaking,apossibleroutetoincreasetheflavourofbread
isbyusingfermentationofallorpartofthedoughinthemanufacturing
process.However,itshouldbenotedthattheoverallflavourprofileofthe
finalproductwillbedifferentandmaybelessacceptabletoallconsumers.
Againitmaybeamatterofeducatingtheconsumerpalate.
Theotheruniversalfunctionofsaltinbakedproductsisthatofapreser-
vative.Additionsofsalthavebeenusedtoextendthemould-freeshelf-life
ofcakesandmanyotherbakeryproducts(
CauvainandYoung,2008
).
Weightofweight,saltis11timesmoreeffectivethansucroseinreducing
thewateractivityofabakedproduct,soithasbeenacommonadditionto
manyrecipes.Ifyouaregoingtouselowersaltlevels,thenyoumayhave
tocompensatefortheincreaseinwateractivitywithotheranti-microbial
strategies.Inhighwateractivityproducts(e.g.,bread,hot-plategoods),the
impactofsaltonproductmould-freeshelf-lifeisverysmall.However,
thewateractivitylevelsinsuchproductsaremarginalforropespoilage
(see
Section4.1.4
),soreductionsinaddedsaltlevelsshouldbeapproached
withsomecaution.Ropespoilageismorelikelytobeaprobleminwhole-
meal,andmixedgrainbreadsasthespore-formingbacteriaareassociated
withtheotherlayersofgrainssosporecountsarelikelytobehigher.
Saltplayssometechnologicalrolesinthemanufactureofbreadand
otherfermentedproducts.Oneoftheseistolimittheactivityofbakers
yeastinthedough.Reductionsinaddedsaltlevelswillleadtoincreased
102
BakingProblemsSolved
gasproductionbytheaddedyeastsuchthatthedoughmaybecomeover-
provedinastandardprooftimeinthebakery.Insuchcases,itmaybe
necessarytoeitherreduceprooftimesorloweraddedyeastlevelsinthe
dough;thelatterismostcommonlypreferredasthelengthoftimeused
fordoughprovinghasothertechnologicalbenefitsrelatedtotherheological
propertiesofthegluteninthedough;mostnotablytocontributetothe
uniformityofovenspringwhentheproductisbaked.
Saltalsomakesacontributiontodoughdevelopmentandbreadvolume.
DannoandHoseney(1982)
showedthatMixographtimestopeakwere
shorterwhensaltlevelswerereduced,whereasotherstudies(
Millerand
Hoseney,2008
)haveshownthatloafvolumeswereoptimisedataround2%
flourweightandthatvolumedecreasedwhensaltlevelswerebothincreased
anddecreased.Anylossesinbreadvolumecanbecompensatedforby
otheringredientandrecipeadjustments.Loweringsaltlevelsinbreaddough
doesleadtosomeadversechangesindoughrheologicalpropertiesafter
mixing.Inparticular,thereisanincreaseindoughstickinesswhichmaybe
ofconcerninhighlyautomatedplantsorwhereambientdoughprocessing
temperaturesarehigh.
References
Cauvain,S.P.,Young,L.S.,2008.BakeryFoodManufactureandQuality:WaterControland
Effects,seconded.Wiley-Blackwell,Oxford,UK.
Danno,G.,Hoseney,R.C.,1982.Effectofsodiumchlorideandsodiumdodecylsulphateon
mixographproperties.CerealChem.59,202

204.
Miller,R.A.,Hoseney,R.C.,2008.Roleofsaltinbaking.CerealFoodsWorld,Jan

Feb,4

6.
Furtherreading
Kilcast,D.,Angus,F.,2007.ReducingSaltinFoods:PracticalStrategies.WoodheadPublishing
Ltd,Cambridge,UK.
RawMaterials
Chapter|2
103
2.5.5Weareusingwalnutsinourgateaubuttercreamfilling
andfindthatitturnsblack.Itdoesnotappeartobemould.
Whatisthecauseofthisdiscolouration?
Youarequiterighttheproblemisnotoneofthemouldgrowth.Themost
likelycauseisareactionofthetannininthewalnutpieceswithanytraces
ofironwhichmaybepresentinthecream,perhapspickedupfromthe
mixingutensilsthatyouhaveused.Thecolourmaytakeseveraldaysto
2.5.6Whatistheroleofemulsifierintheproductionofsponge
cakeproducts?
Thekeyrolefortheemulsifieraddedtospongecakebattersisassistinthe
incorporationandstabilisingoftheairbubblesmixedintothecakebatter.
ThemostcommonemulsifierusedinspongecakemakingisGMSthough
polyglycerolestersarealsoused.Inbothcases,theemulsifiercanbe
consideredasamoleculewhichhasa
hydrophobic(water-hating)head
andahydrophilic(water-loving)tail.Thus,whentheemulsifierisused
inacakebatter,thehydrophobichea
dalignsitselfattheinterfaceof
theliquidandairphases,whereast
hehydrophilictailislocatedinthe
liquidphase.Theseactionsconfers
tabilitytotheairbubblesincorporated
duringmixing.
Spongecakesmaybemadewithoutanyemulsifier,andinthiscase,
theeggproteinsplaythebubblestabilisingrole.However,ifanyfatoroilis
presentintheformulation,thentheeggproteinscannotmaintaingas-bubble
stabilityduringbakingandthecakemayexhibitcollapseandcoreformation
(see
Section5.41
).Toovercomethisproblemwhenusingfatoroil,itis
necessarytoaddanemulsifier.Inthiscase,theemulsifiertakesoverthegas
bubblestabilisingroleoftheeggproteins.Itisimportanttoensurethatsuffi-
cientemulsifierisaddedtomaintaingasbubblestabilityinboththecold
batterandduringbaking.
CauvainandCyster(1996)
showedhowcorefor-
mationwasmadeworsewhenalowlevelofGMSwasaddedtothebatter
butwaseliminatedasthelevelprogressivelyincreased.
Gasbubblesizeandthereforespongecakecellstructureisdirectly
affectedbythelevelofemulsifier.
CauvainandCyster(1996)
studiedthe
effectsofGMSandfoundthattheminimumgasbubblesize,andtherefore
finestcellstructure,wasobtainedatabout0.6%batterweightwiththeirfor-
mulation(see
Fig.2.8
).IncreasingthelevelofaddedGMShadnoeffecton
gasbubblesize,butat1.5%batterweight,thecakewasunacceptable,hav-
ingaloosecrust,manysurfaceblistersandaveryclosecellstructure.This
thickaroundthegasbubblesthattheywereunabletorupture(i.e.,convert
fromfoamtosponge)atthecorrectmomentduringbaking.
Thevolumeofgasthatcanbeincorporatedintothebatterisalsorelated
tothelevelofemulsifierused.Thehigherthelevelofemulsifier,the
greaterthevolumeofairthatcanbeincorporatedandthelowerthebatter
relativedensitythatcanbeachieved.Thisinturncanleadtogreaterprod-
uctvolumeprovidedthatsufficientemulsifierispresenttoensurebubble
stabilityduringbaking.
Toensurethattheemulsifieriseffectiveasabubblestabiliser,itis
importanttouseitinitsmostappropriateform.InthecaseofGMS,there
RawMaterials
Chapter|2
105
areanumberofdifferentformsinwhichitcanexist,dependingonitscon-
centrationinwaterandthetemperatureofthepreparation.
KrogandLarsen
(1968)
studiedthephasediagramforGMSandwaterandshowedthatthe
mosteffectiveformforcakemakingoccurredoveralimitedrangeofconcen-
trationsandtemperatures.Themostappropriateformisoftencalledthe

alpha
gelform.Commonly,cakeemulsifiersareusedinaready-prepared
gelformandmaycontainaco-emulsifiertopreventGMSreversionwhen
themixtureiscooled.
References
Cauvain,S.P.,Cyster,J.A.,1996.Spongecaketechnology.CCFRAReviewNo.2.CCFRA,
ChippingCampden,UK.
Krog,N.,Larsen,K.,1968.Phasebehaviourandrheologicalpropertiesofaqueoussystemsof
industrialmonoglycerides.Chem.Phys.Lipids2,129

135.
Furtherreading
Whitehurst,R.J.,2004.EmulsifiersinFoodTechnology.BlackwellPublishing,Oxford,UK.
FIGURE2.8
Effectoflevelofemulsifieronbubblesizeinspongecakebatter.
106
BakingProblemsSolved
2.5.7Whatingredientsarecommonlyusedaspreservatives?
Arethereanyparticularbenefitsassociatedwithdifferentones?
Thechoiceofpreservativedependsontheproducttypeandthepotential
microogranismswhichareprevalentincausingspoilage.Microbialspores
areairborneinthebakeryenvironmentandalsopresentinthedryingredi-
ents(flour),theirpackagingandthroughcontactwithcontaminatedequip-
mentandsurfaces.Preservativesonlyinhibitspoilage

theydonotdestroy
themicroorganismsandsogoodhygieneisanecessaryadjuncttousing
preservatives.
Acomprehensivelistofpreservativesforuseinbreadandfinebakers
waresisgivenby
Cauvain(2015)
.Breadsandotherfermentedproductsare
highinmoistureandaresusceptibletomicrobialattack.
Table2.3
shows
someofthecommonlyusedpreservativesalongwiththeirrecommended
levelsofusewithintheEuropeanUnion;thereareotherlocallimitsfortheir
additionandtheseshouldbecheckedbeforeuse.Usingthematerialsattheir
recommendedlevelsshouldensureanextensionofmould-freeshelf-lifeby
2

3daysattemperaturesof20

C.Vinegarisusedtocombatropebacterial
spoilageandhasasmallinhibitingeffectagainstmoulds(see
Section2.5.8
).
Forflourconfectioneryproducts,suchascakesandmuffinswith
intermediatemoisturelevels,thecommonlyusedpreservativesaresorbic
acidanditssalts.Theyarenotefficaciousinbreadandfermentedproducts
asthelevelsrequiredrenderthedoughstickyanddifficulttoprocess,inhibit
theactionofbakersyeastandyieldproductswithpoorvolumeandcoarse,
openstructure(unlessaddedintheirencapsulatedform).Sorbicacidand
itseasierhandledsalt

Potassiumsorbate

canbeaddedupto2000ppm
(inthefinishedproduct).Thelevelsuseddependontheproductwateractiv-
ityandpH.Addingpreservativestogivemorethana50%extensionto
shelf-lifeisnotusuallyrecommended(
CauvainandYoung,2008
)asthepre-
oftheproduct,thegreaterthepreservativeeffectasshownin
Fig.2.9
.
Aceticacidanditssaltsmaybeusedinmanybakeryproductsalthough
theyarelesseffectivethanothersmentionedhere.Insomecases,theuseof
TABLE2.3
CommonPreservativesforBreadandFermentedProducts
PreservativeRecommendedusage(%offlourweight)
Calciumpropionate0.2
Propionicacid0.1
Sodiumpropionate0.2
Sodiumdipropionate0.2
RawMaterials
Chapter|2
107
commercialpreferences.Aswithallpreservatives,highlevelsofaddition
producedistinctiveodoursandtasteintheproducts,andonceconsumers
havebecomeaccustomedtothese,itmaybedifficulttointerchangethem.
ForproductssuchasDanishpastrieswithrelativelyshortshelf-life,
preservativesarelesscommonlyused.Ifthepastriesarefermented,thenthe
preservativesusedinbreadswouldbesuitableandforcake-likeonessorbic
acidanditssaltswouldbeappropriate.Forlowmoisturebiscuitsandcook-
iesmouldgrowthisnotusuallyaproblemandsotheadditionofpreserva-
tivesisnotcommon.
Insomecases,itmaybeappropriatetouseacombinationofpreservatives
toachievethedesiredeffectonshelf-life.Thisisbecausetherearemany
differenttypesofmouldsandeachofthemcantolerateaslightlydifferentset
ofconditionsandtypeofpreservative.Inmostmanufacturingenvironmentsit
isunlikelythatthefullrangeofmoulds
typescontaminatingaproductwillbe
known.Therearesomeverycommonones(e.g.,
Penicillium
sp.,
Aspergillus
sp.)
andusuallytheadditiononepreservative
isallthatisrequired.However,insome
cases,abroadspectrumapproachwithamixtureofpreservatives(andother
inhibitoryprocesses)maybeusedtoens
uremaximumimpact.Withmixturesof
preservatives,theextensionofthem
ould-freeshelf-lifeoftheproductmaybe
increasedbeyondthatachievedwithas
inglepreservativethoughtheoverall
impactmaybedifficulttoquantify.
References
Cauvain,S.P.,2015.
TechnologyofBreadmaking
,thirded.SpringerPublishingInternational
AG,Switzerland.
Cauvain,S.P.,Young,L.S.,2008.BakeryFoodManufacture&Quality:WaterControland
Effects,seconded.Wiley-Blackwell,Oxford,UK.
Additional days shelf-life for cake at different pHs
treated with 1000ppm sorbic acid
0
50
100
150
200
250
300
350
55.566.57
pH
Extra days shelf-life at
21C
ERH 92%
ERH 86%
ERH 80%
FIGURE2.9
Additionaldaysshelf-lifeobtainedincakesofdifferentpHswhentreatedwith
sorbicacidat1000ppmproductweight.
108
BakingProblemsSolved
2.5.8Whateffectdoesvinegarhaveonbreadandwhy
isitadded?
Vinegarhastheadvantageofbein
gconsideredbymanyasanatural
inhibitorforthegrowthofropebacteria(
Bacillussubtilis
)inbread.Asa
preservative,ithaslittleintrinsicant
imicrobialactivityandsoisaddedto
increasetheacidity(reducethepH
thebacteria.Ropesporesarepresentnaturallyinthesoilandcanbefound
ontheouterpartsofthewheatgrain.Theyarealsopresentintheairand
canbepassedoninflourorbyequipm
entwhichhasbeenincontactwith
contaminateddough(see
Section4.1.4
).
Thewhitespiritformofvinegarisdilutedtoagivea12.5%solutionand
acidadditionof0.125%basedonflourweight.Suchlevelsreducethebread
crumbtoapHofabout5.4;thegenerallevelsuitableforprotectionfrom
rope.Thelevelofadditionrequiredforwholemealbreadsisslightlyhigher.
ToachieveapHof5.4,theamountofvinegaraddedwillvaryfromone
typeofbreadtoanotherdependingonthepHoftheingredients,thenatural
bufferingeffectoftheflourandwhethertheflourhasbeenfortifiedwith
calciumcarbonate.Allflourshaveabufferingeffectontheefficacyof
ofbran.
Fig.2.10
breads.Vinegarhasasmalleffectonthegassingrateofyeast,soyeast
levelsmaybeslightlyincreasedtocounterthisandreducetheimpacton
prooftime.
4.6
4.8
5
5.2
5.4
5.6
5.8
6
00.050.10.150.2
Bread pH
White
Wholemeal
FIGURE2.10
RawMaterials
Chapter|2
109
2.5.9Wehaveheardthatalcoholcanbeusedasa
preservative.Howisthisachieved?
Theuseofalcoholasapreservingagenthasbeenknownformanyyears.
Heavilyfruitedcelebrationcakesareoftentreatedwithalcoholafterbaking
toaddflavourandbenefitfromthepreservativeandanti-stalingproperties.
(
Legan,1993
).
Fig.2.11
showsthepercentageincreaseinmould-freeshelf-
whenthealcoholissprayedontoallsurfacesoftheloafbeforepackingand
sealing.Ifthealcoholiscoatedontheinsideofthebagbeforeinsertingthe
loafandsealing,theincreaseinshelf-lifeissimilar.Thealcoholactsasa
vapourpressureinhibitoranddiscouragesmouldsfromgrowing.Inthecase
ofbread,additionofalcoholatlevelshigherthan1%ofproductweightcan
Ifadding,alcoholtofermentedproductsorcakeschecksshouldbemade
onpossiblelocalexcisedutiespayableandonanylabellingissues.Although
itmaybecostlytousealcoholasapreservative,ithassignificantpotential
foritsantimicrobialpropertiesandforantistalinginbreadandcakes
(
Cauvain,2015
).
References
Cauvain,S.P.,2015.TechnologyofBreadmaking,thirded.SpringerPublishingInternational
AG,Switzerland.
Biodegrad.32,33

53.
50
0
50
100
150
200
250
300
00.511.5
% by weight of 95% alcohol
% Increase in mould-free shelf-
life
FIGURE2.11
mould-freeshelf-life.
110
BakingProblemsSolved
2.5.10Whatarethepossiblealternativestochemically
basedpreservatives?
Withthedesireforcleanlabels,bakershavesoughtthehelpofingredients
withnaturalpreservativeproperties.Bakershaveknownforcenturiesthe
preservativeeffectofusingdriedfruit,e.g.,raisins,intheircakesandother
products.Sorbicacidsaltsdevelopontheskinsofthefruitastheydryand
togetherwiththehigherconcentrationofsugarwithinthefruitcontributeto
thelongershelf-lifeoftheproduct.Suchpreservativeswillinhibitmicrobial
growthbutwillnotpreventbacterialactivity.Itshouldbenotedhowever
thatforatrulynaturaldriedfruit,thefruitshouldnothavebeentreated
withsulphurdioxideduringthedryingprocess.Manyred-berriedfruitshave
sorbicacidpresentaspartoftheircompositionandifaddedasafruit
concentratemightaddasmallpreservativeeffect.
Inmanycases,thepreservativesfoundinfruitsactbestatlowpHs,
e.g.,circa2.0andsoareeffectivewhenusedinacidicproductssuchasfruit
juicesbutwillhavealimitedeffectinthehigherpHbakeryproducts(asa
generalrulebakeryproductslieinthepHrange5.0to6.5).Benzoateswhich
arefoundnaturallyincranberriesalsoworkbestatlowpH.
Usingaciddoughcomponents,suchasfermentedwheatflour,inbread
canprovideapreservativeeffect.Thisisbasedonthenaturalloweringof
Chapter|2
diastaticmaltpowders,andhowcantheybeusedinbaking?
Maltfloursaremostcommonlymadefromwheat,barleyandtoalesser
extentoats.Afterthemaltingprocess,theproductsofthedifferentcereals
haveslightlydifferentcharacteristics,butessentially,theyfallintotwo
categories;diastaticinwhicharangeofenzymesremainingactiveandnon-
diastaticinwhichtheenzymesareinactivated.
Themaltingprocessisbasedonthepartialgerminationofthegrains.
Initially,thecleanedgrainsaresteeped;thatis,mixedwithapredetermined
quantityofwaterandstoredunderconditionswhichencouragethegrainsto
germinate.Aftertherequisitetime,germinationisarrestedbyremoving
waterwiththeapplicationofgentleheat.Themaltismixedwithwaterand
aliquorextracted.Itisthemaltliquorextractwhichisdriedundervarying
conditionstodeliverarangeofmaltpowderswithdifferentcharacteristics.
Asallenzymesareheatsensitive,thegreatertheheatinputduringdrying,
thelowertheenzymicactivitywhichremainsintheproduct.Alsothegreater
theheatinputthedarkerthemaltpowderwillbe.
thedegreeofflavourintensityvaryingwiththedegreeofheattreatment
usedinthepreparation.Thisdistinctivemaltflavouriscarriedthroughtothe
bakedproductwiththeintensityvaryingaccordingtothegradeofmaltflour
usedanditslevelofaddition.Clearly,themoremaltflourthatisaddedto
theproduct,themorepronouncedtheflavourwillbe.Ifyourmaininterest
inusingmaltistoconferflavourtoproducts,thenyoucanuseeitherthe
diastaticornondiastaticforms.
Thetermdiastaticactivityreferstoasuiteofdifferentenzymeswhich
arepresentinthemaltflour.Thegerminationprocessinthegrainisbased
ontheconversionofstarchtosugarstoprovidefoodfortheearlystages
ofplantgrowth.Thismeansthattheamylaseenzymes,especially
alpha
-
amylase,areasignificantcomponentofdiastaticmaltflours.Asiswell
knownincreasesinthe
alpha-
tionproperties.However,highlevelsofcereal
alpha
-amylasecanleadto
qualityproblemssuchaskeyholing,cavinginonthesidecrust(see
Fig.1.1
and
Section4.1.2
)aswellaspotentialstickinessinthebreadcrumb
andslicingproblems(see
Section4.1.35
).
Otherenzymesmaybeactiveinthemaltpowder,andtheseinclude
proteolyticenzymeswhichcanhaveadverseeffectsonglutenstructures.
112
BakingProblemsSolved
2.5.12Wereadalotaboutthedifferentenzymeswhichare
nowavailableandhowtheymightbeusedinbaking.Canyou
telluswhattheyareandwhatfunctionstheyhave?
Therearemanydifferenttypesofenzymesinthenaturalworld,andtheyare
anessentialpartofthenaturalreactionsinlife.Theymaybedescribedas
organicorbiologicalcatalystswhichacceleratetheratesofcriticalreactions
inplantandanimalsystems.Theyhaveasimilarstructuretoproteins.They
aredescribedasbiologicalcatalystsandareveryspecificinaction;thatis,
theycanonlycatalyseonespecificreaction.Allenzymesoriginatewithin
thecellsofwhichplantsandanimalsarecomposed.Forexample,inthe
bakersyeastcellarealloftheenzymesthatitrequirestobreakdownsugars
andothernutrientsforreproductionandgrowth.
Variousmicroorganismsarethemainsourceofindustrialenzymes.
Specificmicroorganisms(commonlymoulds)aredevelopedunderappropri-
atefermentationsystemsinasimilarmannertothatofbakersyeast.Atthe
endofreproductionandgrowthperiod,thecellsaredisruptedandthecell
contentsrefinedtoseparateoutthedifferentspecificenzymeswhichare
present.Commercialenzymesareusuallyofahighpurity,butmostofthem
willhavesomeresidual,orside-effects,associatedwithotherenzymes
whicharepresentinthesample.Thecommercialproductisusuallytoo
concentratedtobeusedinbakingwithoutbeingdiluted,anditisinthis
dilutedformthatenzymepreparationsareusedintheflourmillandbakery.
Manyingredientsusedinbaking(e.g.,wheatflour,yeast,soyaflour,
maltflour)areenzymicallyactive.Themaingroupsofenzymesusedas
extraadditionsinthemanufactureofbakedgoodsarediscussedbelow.
However,itisimportanttorecognisethatenzymesrequiresuitablecondi-
tionsforthemtoworkeffectively.Asuitablemoisturelevelisoneof
thekeyrequirementsandenzymeactivityindryingredientsislow.Ifthe
moisturelevelislowtheenzymesremaininactivebutwhenthemoisture
levelincreases,theycanquicklybecomeactive.Asmightbeexpectedfora
biochemicalreaction,enzymeactivityistemperaturesensitivewithactivity
graduallyincreasingasthetemperatureisincreased.Allenzymesareeventu-
allyinactivatedbyheatthoughthermalinactivationtemperaturesvary
accordingtotheparticularenzyme,itssourceandtheenvironmentinwhich
itisbeingused.Inbaking,most(butnotall)enzymesareinactivatedby
thetemperaturesachievedintheproductduringovenheating.Otherfactors
whichwillaffectenzymeactivityincludethepH(acidity)oftheenviron-
mentinwhichitused,theavailabilityandconditionofthesubstrateon
whichitactsandthewateractivityofthedoughorbatter.
Beforediscussingthetypesofenzymesandtheirapplicationinbaking,the
questionofspecificityofactionmustbeconsidered.Asstatedabove,enzymes
arehighlyspecificintheiraction,andthisspecificitycanextendbeyondthe
actionofanenzymeonaparticularsubstratetoincludeveryspecificsitesof
RawMaterials
Chapter|2
actionwithinthesubstratemolecularstructure.Itisthisincreasingknowledge
ofthespecificityofenzymesthathaspartlyaccountedfortheincreaseinthe
rangeofproductswhicharenowavailableforuseinbaking.
Theadditionofenzymeactivematerialstobakedproductsishighly
regulated,andinmostcases,thesourceofthatenzymeisspecified.Inmany
partsoftheworld,legislationdoesnotcurrentlyrequireenzymesadditions
tobakedgoodstobelabelled,andtheyfallintothegeneralcategoryof
processingaids.Evenasprocessingaids,theywillhaverequiredformal
approvalforuseintheproductionoffood.

Amylases
Thesearethebestknowngroupsofenzymesusedinbaking.Thereare
twomaintypesofamylase;knownas
alpha
and
beta
responsibleforprogressivelybreakingdownstarch(acomplexcarbohy-
dratecomposedofglucosechains)intodextrins,highmolecularweight
sugarsandfinallytosimplesugarssuchasmaltose(whichcanbeusedby
bakersyeast).Both
alpha
-and
beta
-amylasearepresentinwheatflour.
Thelevelof
alpha
-amylaseactivityvariesdependingonanumberof
factors,notleastofwhichislevelofmoistureinthematuringwheatears.
Beta
-amylaseisusuallyabundantinwheatflours,but
alpha
-amylaselevels
maybelow,soitisacommonpracticetoaugmentitslevelthroughthe
additionofasuitableenzymeactivematerialintheflourmill(
Cauvain,
2017
).Themeasureofcereal
alpha
-amylaseactivityinwheatflouris
measuredusingtheHagbergFallingNumbertest(see
Section2.2.10
).
Thisdescriptionoftheactionofamylasesissimplistic.Starchgran-
ulesinflouraremadeupoftwocomponents;amyloseastraightchained
moleculeandamylopectinabranchedmolecule.Theactionof
alpha
-
amylaseiscommonlydescribedasrandomwithrespecttotheamylose
andamylopectinmoleculeswhilethatofthe
formismorespecific
anditcleavesrelativelysmallmoleculesfromthestarchcomponents
(
Cauvain,2012
).Thus,thecombinedactionofthetwoformsofamylase
iscriticalintheuseofamylaseenzymesasbreadimprover.
Akeyfunctionof
alpha-
amylaseinbreadproductionistoimprove
(
CauvainandChamberlain,1988
).Thesourceofthe
alpha
-amylasehasa
significantimpactontheoveralleffect(
Kulp,1993
;Cauvain,2015).
Someformsofamylaseareknowntohaveanti-stalingeffectsinbread.
Thisarisesfromthegenerationofhighmolecularweightsugarswhich
tionprocessafterbaking(see
Section2.5.13
).

Hemicellulases
Theactionofhemicellulasesisonplantcellwallmaterials

hemicellulose.
Theendospermofwheatiscomposedofsmallcellswhichholdthe
starch,proteinandlipids.Thecellwallsarecomposedofthelargepoly-
114
BakingProblemsSolved
referredtoasxylanases)actont
hecellwallstobreakthematerial
downintomainlyxylose
sultoftheadditionof
hemicellulaseistoincreasedoughg
waterabsorptioncapacity.The
effectofthisgroupofenzymes
iscomplexandtheimpactondough
waterabsorptioncapacitymay
benegativeinsomedoughmakings
ituations,withtheadditionofthe
enzymecausinganincreaseindoughstickiness.

Lipases
andbreadvolume.Theiractionisontriglycerides(fats,lipids)andthe
breakdownproductsofthatactionareinorderdiglycerides,monoglycer-
idesandfinallyfattyacids.Themonoglyceridesformedfromtheaction
oflipaseindoughareknowntocontributeanti-stalingpropertiesin
bread,anditisseenasapotentialreplacementforemulsifiersinbread
recipes(
Rittig,2005
).

Proteolyticenzymes
Thisgroupofenzymesincludeproteasesandproteinasesandtheiraction
softerandmorereadilyprocessable(
Kulp,1993
).Theyshouldbeused
withgreatcare,ifatallinbreadmaking.

Oxidases
thepresenceofoxygen,theycatalysetheoxidationofthe
form
ofglucoseandindoingsoproducehydrogenperoxide.Theabilityof
thehydrogenperoxidegeneratedinthedoughtoaidtheformationofthe
disulphidebondsissaidtobethebasisoftheimprovementindoughgas
).
References
Cauvain,S.P.,2012.Breadmaking:ImprovingQuality,seconded.WoodheadPublishingLtd,
Cambridge,UK.
andApplications,seconded.DEStechPublishing,Lancaster,PA.
Cauvain,S.P.,Chamberlain,N.,1988.Thebreadimprovingeffectoffungal
alpha
-amylase.
J.CerealSci.8(Nov),239

248.
Kulp,K.,1993.Enzymesasdoughimprovers.In:Kamel,B.S.,Stauffer,C.E.(Eds.),Advances
inBakingTechnology.BlackieAcademic&Professional,Glasgow,UK,pp.152

178.
Rittig,F.T.,2005.LipopanFBG

unlockingthenaturalstrengtheningpotentialindough.
In:Cauvain,S.P.,Salmon,S.E.,Young,L.S.(Eds.),UsingCerealScienceandTechnology
fortheBenefitofConsumers.WoodheadPublishingLtd,Cambridge,UK,pp.147

151.
Vemulapalli,V.,Miller,R.A.,Hoseney,R.D.,1998.Glucoseoxidaseinbreadmakingsystems.
CerealChem.75,439

442.
RawMaterials
Chapter|2
115
2.5.13Howdoanti-stalingenzymeswork?Cantheybeusedin
cakeaswellasinbreadandfermentedproducts?
Therehasbeensignificantinterestinusingenzymesasanti-stalingagents
toaugmenttheeffectofemulsifiersortoreplacethem.Whenwereferto
staling,itisinthecontextofslowingdownthefirmingofbreadandcake
crumbwhichcomesfromtheretrogradationofstarchduringstorage.Thisis
incontrasttotheincreasedsoftnesswhichcanbeobtainedbyhighermoisture
levelsinthebakedproductorthroughtheincreaseofproductvolume(the
latteriscommonlyaresultofaddingenzymestobreadformulations).
Therearetwomaingroupsofenzymeswithanti-stalingeffectsinbaked
goods,andthesearespecifictypesof
alpha
-amylaseandlipase;asiswellknown
theformeractsondamagedwheatstarchbreakingitdownprogressivelyto
maltose,whereasthelatteractsontriglyceridestoeventuallyyieldfattyacids.
Thestarchpolymerconsistsofaseriesofsugarmoleculeslinkedtogether
aslinearchainsofamyloseandbranchedamylopectinstructures.
Alpha
-
amylaseisabletocutthroughtheselinkagesatdifferentpointsbutvery
specificpointsdependingonthetypesofamylasetoyielddifferentsugarsof
varyingmolecularweights.Sugarsareknowntofunctionasanti-stalingingre-
dientsinstarch-basedfoods,probablybyraisingtheglasstransitiontempera-
ture(see
Section11.6
)andsuppressingtherecrystallisationofthe
amylopectin(themaincomponentresponsibleforstalinginbread).
Inthecaseoflipasethespecificactionistogeneratemonoglyceridesin
situinthedoughandmonoglyceridesareprovenanti-stalingagentsinbread.
Again,thespecifictypeoflipasewilldictatewhichspecificmonoglyceride
isgeneratedandatwhatrateandlevelinthebreaddough.
Theanti-stalingeffectofsomeenzymesisnowwellestablishedinbread.
Incakes,itislesswellestablished.Astheactionofthespecificanti-staling
alpha
difficulttoseewhythisshouldbeofsignificantbenefitincakeswhich
alreadybyvirtueoftheirformulationcontainhighlevelsofsugars.Thereis
someevidencewhichsupportsincreasedsoftnessvaluesforcakecrumb
containingspecificlipases.Thisisperhapsmoreunderstandableduetothe
generationofthemonoglyceridewhichisknowntohavecrumbsoftening
effectsincakemaking.
Itislikelythatanyobservableanti-stalingeffectsofenzymeswilldepend
heavilyonthetypeofcakebeingproducedandismorelikelytobeobserved
inlow-fatcakes,suchassponge,orlow-ratiocakeswherethelevelsofsugar
arelower.
Furtherreading
Cauvain,S.P.,2012.Breadmaking:ImprovingQuality,seconded.WoodheadPublishingLtd,
Cambridge,UK.
116
BakingProblemsSolved
2.5.14Whatislecithinandhowisitusedinbaking?
Lecithinisanaturallyoccurringemulsifierfoundinanimaland
majorsourceofthematerial.Itisaliquidattemperaturesaround20

Cand
issolubleinoil.Purifiedandmodifiedformsareavailableasaplasticliquid
andinpowderform(oftenblendedwithanotherfoodgradepowderforease
ofhandling).Themainconstituentoflecithinintermsofitsfunctionalityis
amixtureofphospholipidswiththecombinationofthedifferenttypesbeing
specifictoitsanimalorplantsource.
Asacomponentofeggyolk,lecithinplaysaroleinhelpingtostabilisethe
airbubblesthataremixedinduringthepreparationofcakebatters.Thisroleis
especiallyimportantinthepreparationofspongeproductswhichtendtohave
lowlevelsofaddedfatoroil.Thelecithinphospholipidsarepartoftheegg
lipoproteinswhicharefoundattheinterfaceoftheairwiththeaqueousphase
incakebattersandaidbubblestabilityatthetimeintheovenwhenthecake
battersystemchangesfromawater-in-oiltooil-in-wateremulsion.Lecithinis
oftenusedalongwithotheremulsifiers,suchasGMS,inspongecakemaking.
Theadditionoflecithinatlowlevelsinthemanufactureofcakedough-
nutsissaidtoreducefatabsorptionduringfryingandtoconfertendernessto
thefinalproducteatingqualities.
Lecithinmaybeusedinthemanufactureofsomebreadtypes.Itenhances
gasretentioninthedoughtoadegreebutlesssothanothermorecommonly
usedemulsifiers.Incrustybreads,ittendstogiveathicker,densercrustwhich
retainsitscrispnessforlongerperiodsoftime(
Cauvain,2015
).
Inbiscuits,lecithinmaybeusedasameansofreducingfatlevelsbyupto
10%withoutadverselyaffectingbiscuitquality.Dissolvingthelecithininfat
makesiteasiertohandle(
Manley,2000
),anditmayhelpwiththedispersion
ofthefatthroughoutthedoughgivingitasmootherfeel.Inhighersugarcook-
ies,theadditionoflecithinhelpswiththerestrictionofflowduringbaking.
Inthebakery,lowlevelsoflecithin(around5%)areoftenfoundasa
componentofoil-basedpangreasingagents.
References
Cauvain,S.P.,2015.TechnologyofBreadmaking,thirded.SpringerPublishingInternational
AG,Switzerland.
Manley,D.,2000.TechnologyofBiscuits,CrackersandCookies,thirded.Woodhead
PublishingLtd,Cambridge,UK.
Furtherreading
Silva,R.,1993.Lecithinandphospholipidsinbakedgoods.In:Kamel,B.S.,Stauffer,C.E.
(Eds.),AdvancesinBakingTechnology.BlackieAcademic&Professional,Glasgow,UK,
pp.223

253.
Whitehurst,R.J.,2004.EmulsifiersinFoodTechnology.BlackwellPublishing,Oxford,UK.
RawMaterials
Chapter|2
117
2.5.15Wehavebeenhavingsomeproblemswiththequalityof
ourbread,pastriesandbiscuitsandonesolutionthathasbeen
recommendedtousisthatweshouldaddareducingagentto
ourrecipes.Canyoutellusmoreaboutreducingagents,and
howtheyfunctioninbakedproducts?
Weshouldfirststartbydefiningwhatwemeanby
reduction
.Inchemical
terms,itisusedtodescribereactionsinwhichhydrogenisaddedtoan
elementorcompound,orinwhichoxygenisremovedfromacompound.
Itistheoppositeof
oxidation
.Althoughbothtermsareusedempiricallyto
coveranumberofsimilarreactions,inbaking,thereductionandoxidation
reactionswhichtakeplaceareveryclosetotheformaldefinition.
Akeyreactionduringmixingistheformationofdisulphidebonds
Cauvain,2015
).Theirformation
ispromotedby
oxidation
,andtheycontributetotheelasticityofdough.
Theoriginsofthispropertyareassociatedwiththeratioofgluteninto
gliadinproteinsinthewheatflourthoughoxidationprocesseswhichoccur
duringdoughmixingalsomakeacontribution.Ifthedoughistooelastic
aftermixingthenitmaybedifficulttoprocess,anditiscommontoconsider
addingareducingagenttoreducethenumberofdisulphidebondswhich
havebeenformed.
Acommonlyusedreducingagentinthepreparationoffermenteddough
is
L
-cysteine,anaturallyoccurringaminoacidusedinthehydrochloride
formtoimproveitssolubility.Theadditionof
L
-cysteinehydrochloride
isoftenrecommendedtoreducethelevelofworkinputrequiredforthe
manufactureofbreadbytheCBPorsponge-and-doughprocesseswhen
usingverystrongfloursorencounteringdifficultieswithdoughmoulding.
Thisapproachshouldonlybeusedwhenthereisnoalternative,more
suitableflouravailableastheresultofusing
L
-cysteinehydrochlorideare
oftenunequivocal.
Theadditionof
L
-cysteinehydrochloridehasbeenshowntobebeneficial
inthemanufactureofotherfermentedproductsandhasbecomeacommon
ingredientindoughconditionerandimproversaddedintheproductionof
rolls,pizzabases(
Cauvain,2015
)andhamburgerbuns.Withallofthese
bakeryproducts,themaineffectofthe
L
-cysteinehydrochlorideistoreduce
theelasticityofthedoughandtoassistinachievingthedesiredshape
withoutcausingunduedamagetothedoughpiecesduringmoulding.
L
cysteinehydrochloridealsofindspotentialuseinthemanufactureof
involved.Theglutenstructureislesswelldevelopedinshortpastrymaking
thanwithlaminatedpastes,butbothcanbenefitfromtheadditionofareduc-
ingagent.Inpastrymaking,analternativetotheadditionof
L
-cysteine
118
BakingProblemsSolved
tobeusedwithcareinthemanufactureofpastryproductsbecausethe
recyclingoftrimmingscanleadtotheirprogressivelyincreasingconcentra-
tionintherecipesbeingusedwithsubsequentexcessivesofteningofthe
paste.Longdelaysinpasteprocessingcanalsoleadtoexcessivesoftening
ofthepastewhenreducingagentsarepresentintherecipe.
tureofbiscuits,especiallythelow-fat,low-sugartypesembracedbythe
achievedinbreaddoughmixing,butwithstrongerflours,itisstillsufficient
tocontributetobiscuitshrinkage.Thisshrinkagemaybeseenduringthe
ting,whereasinlessseverecases,itmayonlybeobservedasshrinkageafter
thebiscuithasbeenbaked.Inthiscase,thebiscuitdimensionswilldiffer
fromthoseusedincuttingandroundbiscuitshapescommonlydevelop
(
Manley,2000
),andcommonadditive-freeapproachesaretomoreclosely
specifythequalitiesoftheflourtobeusedortoaddmorewaterduring
Theconcernovertheadditionofche
micalreducingagentshasled
toconsiderationofmorenatural
forms.Bakersyeastcellsarearich
sourceofthenaturalreduc
ingagentglutathione(
BonjeanandGuillaume,
2003
).Inscratchbreadmakingtheyeast
cellsareintactandtheglutathione
hasnodirectcontactwiththedoughproteins.However,iftheyeastcell
membraneisdamaged,thenthereispot
entialfortheglutathionetoreact
astandyeasteddoughsleadstoirrep-
arabledamagetothecellmembrane,andtheeffectoftheglutathione
frozenbreaddough.Commercialextractsofyeastcellcontentsareavail-
ableforuseasareducingagent.Glutathione(and
L
-cysteinehydrochloride)
maybeusedinthemanufactureofpastatodenaturethegluteninthedough
(
KentandEvers,1994
).
Glutathioneoccursnaturallyinflour.Itisamongthelowmolecular
weightthiolcompoundsthoughtheamountsarepresentinflouraresmall.
Lowmolecularweightthiolsdiffuserapidlythroughthedough,sodespite
theirlowconcentrations,theyarelikelytobeactiveinaffectingtherheolog-
icalpropertiesofthedough.Insomeinstances,changesinglutathionelevel
havebeenlinkedwiththefreshnessofflouranditsperformanceinbaking
(
ChenandSchofield,1996
).Glutathionelevelsdovarywithwheattype
andtheashcontentoftheflour(
).Thecontentoflow
molecularweightthiols(includingglutathione)isknowntobeaffectedby
oxygen,probablyduringthemillingofwheattoflourandalmostcertainly
RawMaterials
Chapter|2
119
duringdoughmixing.
foundthatdoughresistancefell
andflourextensibilityincreasedasthelevelofglutathioneincreased.
includingsomediscussionoftheroleofascorbicacid(AA).Chemically,AA
isareducingagent,butitsconversiontodehydro-ascorbicacid(DHA)is
responsibleforitsoxidisingeffectsinbreadmaking(
Cauvain,2015
).The
availabilityofoxygenfortheconversioniscrucialinthiscontext,butas
(
CauvainandYoung,2006
).Thissuggeststhatintheanaerobicenvironment
inthedoughwhichisattainedaftermixing,theAApresenthasthepotential
toactasareducingagentandpracticalexperimentsshowthatifAAis
presentinfermentingdough,thentherecanbelossofbreadvolume
(see
Section4.1.24
).However,ifthedoughisre-mixed(e.g.,asduring
knock-back,see
Section9.7
),thenthereintroductionofoxygenallowsfor
somefurtheroxidationeffectfromtheAA.
References
Bonjean,B.,Guillaume,L.-D.,2003.Yeastinbreadandbakingproducts.In:Boekhout,T.,
Robert,V.(Eds.),YeastsinFood.WoodheadPublishingLtd,Cambridge,UK,pp.289

308.
Cauvain,S.P.,2015.TechnologyofBreadmaking,thirded.SpringerPublishingInternational
AG,Switzerland.
Cauvain,S.P.,Young,L.S.,2006.TheChorleywoodBreadProcess.WoodheadPublishingLtd,
Cambridge,UK.
Chen,X.,Schofield,J.D.,1996.Changesinglutathionecontentandbreadmakingperformance
ofwhiteflourduringshort-termstorage.CerealChem.73,1

4.
Keiffer,R.,Kim,J.-J.,Walther,C.,Laskawy,G.,Grosch,W.,1990.Influenceofglutathioneand
cysteineontheimprovingeffectofascorbicacidstereoisomers.J.CerealSci.11,143

152.
Kent,N.L.,Evers,A.D.,1994.TechnologyofCereals,fourthed.ElsevierScienceLtd.,Oxford,UK.
Manley,D.,2000.TechnologyofBiscuits,CrackersandCookies,thirded.Woodhead
PublishingLtd.,Cambridge,UK.
andtotalglutathioneinwheatflourbyanisotopedilutionassay.ZLebensmUntersForsch
195,27

32.
Furtherreading
Kulp,K.,Lorenz,K.,Brummer,J.,1995.Frozen&RefrigeratedDoughsandBatters.AACC,
St.Paul,MN.
Weiser,H.,2015.Theuseofredoxagents.In:Cauvain,S.P.(Ed.),BreadMaking:Improving
Quality,seconded.WoodheadPublishingLtd.,Cambridge,UK,pp.447

469.
120
BakingProblemsSolved
2.6AERATION
2.6.1Ihaveheardthatyeastrequiresoxygenbeforeitcan
workcorrectly,isthistrue?
Aslongagoas1875,LouisPasteurshowedthatfermentationcouldtake
ofoxygeninhibitedfermentationbutincreasedyeastgrowthandrespiration.
Pasteursobservationthatfermentationislifewithoutairisawell-known
quotationinfoodscience.
Ifoxygenisintroducedinincreasingquantitiesintoafermentingsugar
solution,fermentationslowsdownandrespirationtakesover.Theprocess
canbedescribedchemicallyasfollows:
C
6
H
12
O
6
1
6O
2
5
6H
2
O
1
6CO
2
Glucose
1
oxygen
5
water
1
carbondioxide
muchofthecarbondioxidewhichisliberatedcombineswithothermaterials
toformyeastcellsubstance.Theyeastmanufacturermakesuseofthe
effectofoxygenbyblowinglargevolumesofairthroughthefermenterto
discouragefermentationandsomaximisetheyieldofyeast.
arisebecauseofthewell-knowneffectofyeastscavengingoxygenmolecules
fromabreaddoughduringmixing.Theimportanceofthisobservationis
thatitexplainswhytheeffectofascorbicacidasanoxidisingagentislim-
itedtothemixerinbreadmaking(see
Section2.7.3
).
RawMaterials
Chapter|2
121
2.6.2Howdoesbakersyeastproducecarbondioxidein
breadmaking?
Yeastproducescarbondioxidegasinbreadmakingbyfermentingthesugars
whicharepresentintheingredientsortheformulation.Thebasicreactionis
representedinthefollowingmanner:
C
6
H
12
O
6
5
2C
2
H
5
OH
1
2CO
2
Glucose
5
1
carbondioxide
Youwillnoticeasignificantdifferenceinthereactioncompared
withthatgiveninthepreviousquestion.Inparticular,fermentationyields
requirethepresenceofoxygen.
Theyeastcellcontainslargenumbersofenzymeswhicharerequiredfor
thefermentationandrespiration.Theseenzymesareheldwithinthecell
membraneprovidedthecellwallremainsintact.About14differentenzymes
areinvolvedinthefermentationprocess.
Whenadoughismade,theyeastfirstfeedsonthenaturallyoccurring
sugarsintheflour(glucoseandsucrose).Astheseareusedup,theenzyme
complexbeginstoprovidemoresugarsbybreakingdownotherflourcompo-
nents.Thedamagedstarchisimportantinthiscontextduetoitsconversion
ultimatelytomaltosethroughthecombinedactionsof
alpha
and
amy-
lases.Thisiswhyweareconcernedwiththeenzymicactivityanddamaged
starchlevelsintheflourthatweuse(see
Section2.2.11
).Ifwecannotpro-
videasubstrate(food)fortheyeast,itwillstopworkingandcarbondioxide
productionwillcease.
Inmodernno-timebreadmakingprocesses,weareonlyconcernedwith
theproductionofcarbondioxidebytheyeast.Respirationandgrowthare
notrequired.Indeed,theconditionswithinabreaddoughformulation
andtheproductiontimescalesconcernedareunlikelytobesuitableforeither
respirationorgrowthtotakeplacetoanysignificantdegree.
122
BakingProblemsSolved
2.6.3Arethereanyparticularprecautionsthatweshouldtake
inhandling,storingandusingbakersyeastinthecompressed
form?
Tooptimisetheperformanceofbakersyeast(
Saccromycescerivisii
)inthe
manufactureofbreadandfermentedproducts,itisimportanttoensurethatit
iskeptinitsoptimumcondition.Individualyeastcellsarecharacterisedby
havingamembranewhichenclosesthecellcontents(
Cauvain,2015
).Itis
theenzymesinthelatterthatprovidetheyeastwithitsabilitytoproduce
contents,themembraneplaysacriticalroleinregulatingtheflowofnutri-
entsintoandby-products(e.g.,carbondioxide)outofthecells.Theflowof
nutrientsiscontrolledbyosmoticpressure(
CauvainandYoung,2008
)(see
Section11.12
).
Compressedyeastispre
paredundercarefullycontrolledconditionsin
thefactory(
Cauvain,2015
).Akeyrequirementisthatthecells(approxi-
mately15thousandmillionperg)ar
eintact(undamaged)andviable
(alive).Toensurethisandtominimi
seactivityintheblockcompressed,
yeastiscommonlydeliveredatrefrig
eratedtemperatures,typically4

8

C
andshouldbeheldatthesetemperaturesuntilrequiredforuse(see
Section2.6.3
).
Theparticularprecautionsthatyoushouldtakeinclude:

Transfertheyeastintorefrigeratedstorageassoonaspossibleafter
delivery.Prolongedexposuretowarmtemperaturescanleadtolossof
activitythoughautolysis.Thisprocessischaracterisedbyadarkening
ofthecornersofthecompressedblockswhichmayalsospreadingalong
theedgesoftheblocks(see
Section2.6.4
).

Avoidhavinglargequantitiesofyeaststandinginthewarmbakery
waitingtobeused.Trytoestablishaworkingpatternwhichdrawsout
sufficientyeastfor1

2hoursofproductionthroughouttheday.

Breakdownlargeblocksintoacoarsecrumblebeforeaddingthemtothe
mixerasthiswillaiddispersionthroughoutthedough.Youmaywantto
dispersethecrumbledyeastintosomeoftherecipewaterbeforeyouuse
it,butthisisnotessentialwithmodernyeaststrainsandbreadmaking
practices.

Donotkeepusingtheyeastafteritsshelf-lifedatehasexpired.Thereisa
slowbutprogressivelossofgasproductionpowerintheyeastduringstor-
age,evenunderidealrefrigerationconditions(see
Fig.2.12
).Thiswill
resultinanincreaseinprooftimeorrequiretheadditionofextrayeastto
maintainproductproofvolume.Itmayalsoleadtolossofbreadvolume
throughtheactionofglutathionefromanyyeastcellswhichhavedied.

Donotleavecompressedyeastblocksunwrappedforlongperiodontime
astheycandryoutandloseactivity.
RawMaterials
Chapter|2
123

Ensurethattheconditionsunderwhichtheyeastisstoredremain
optimum.Itisimportantthatthecellmembranesremainintact.Amongst
thecellcontentsareapowerfulreducingagentknownasglutathione.
alsocausesexcessiveflowofdoughintheprover.

Fluctuationsinstoragetemperaturescanleadtotheformationof
unwantedmouldcoloniesonthesurfacesoftheblocksiftheyhavebeen
exposedunwrappedtotheatmosphereandsoshouldbeavoided.

Avoidfreezingtheblocksastheformationoficecrystalsinsidethecells,
theirgrowthduringstorageandsubsequentdefrostingresultsinrupturing
ofthecellmembranesandthereleaseofthecellcontents.
References
Cauvain,S.P.,2015.TechnologyofBreadmaking,thirded.SpringerPublishingInternational
AG,Switzerland.
Cauvain,S.P.,Young,L.S.,2008.BakeryFoodManufacture&Quality:WaterControland
Effects,seconded.Wiley-Blackwell,Oxford,UK.
330
310
290
270
250
230
210
190
170
150
02856
Storage time (days)
Volume per produced in 5h (ml)
FIGURE2.12
Effectofyeaststoragetimeongasproduction.
124
BakingProblemsSolved
2.6.4Whatarethecausesofthedarkbrownpatcheswe
Chapter|2
2.6.5Wehavebeenadvisedtostoreourcompressedyeast
intherefrigeratorbutourdoughtemperatureismuchhigher,is
thisthecorrectthingtodo?
Theadvicethatyouhavebeengivenisabsolutelycorrect.Oncecompressed,
yeasthasbeenprepared;itshouldbekeptunderrefrigeratedconditions
(4

C)untilitisrequiredfordoughmaking.Storingyeastathigherthan
refrigeratedtemperaturesresultsintheprogressivelossofitsgasproduction
potential.
Cauvain(2015)
providesdatatoshowhowdoughprooftimes
wereincreasedwhencompressedyeastwasstoredat10

Cand15

C.Bythe
timethattheyeasthadbeenheldfor14daysat15

C,theprooftime
requiredforthedoughhaddoubled.Storingcompressedyeastatdoughtem-
peratureswouldbeadisaster!
Itisthereforeveryimportantthattheyeastisstoredunderthebestpossi-
bleconditions.Storingat4

Creducesthepotentialforunwantedactivity
withintheblock(see
Section2.6.3
).Thecompressedyeastisusuallytrans-
portedunderrefrigeratedconditionsandondeliveryshouldbemovedas
quicklyaspossibletostorageatasimilarstoragetemperature.Theblocks
shouldbeleftintherefrigeratoraslateaspossiblebeforeuse.Oncedis-
persedintothedough,thecellssoonwarmandproducecarbondioxide.
Variationsingassingactivitywillshowasvariationsinproofvolumefor
agiventime.Ifyouarenotabletoadjusttheprooftimetocompensatefor
andproblemswithproductshape,e.g.,raggedbreaksfromunder-proof(see
Section4.1.3
).
Reference
Cauvain,S.P.,2015.TechnologyofBreadmaking,thirded.SpringerPublishingInternational
AG,Switzerland.
126
BakingProblemsSolved
2.6.6Wehaveseenreferencestoalagphaseforbakers
yeast;whatdoesthismeansandwhataretheimplicationsfor
baking?
Bakersyeast(
S.cerivisii
)isoneofmanydifferenttypesofyeastwhichmaybe
usedorfoundinfoods(
BoehhoutandRobert,2003
).Likeallmicroorganisms
whenplacedinasuitableenvironmenttheybegintofeed,andmultiply.This
processstartsveryslowlybutastimeprogressestherateofactivityincreasesif
thetemperatureremainsconstantandthereisareadysupplyoffood.
Thekeyfunctionofbakersyeastinbakingistheproductionofcarbon
dioxidegas.Modernstrainsofbakersyeastarefarmorereliablethan
thosewhichhavebeenusedtraditionally.Intheflourthereisaninitial
supplyofnaturallyoccurringsugars,typically1

1.5%byweightandthese
arefermentablebytheyeast.Later,asthecombinationof
alpha-
and
-
sugarintheformofmaltosebecomesavailabletosupportfermentation.
Sugarsmaybeaddedtothedoughformulationthoughinno-timedough
processestheadditionofextrasugartosupportfermentationisnotusually
necessarybutitmaybeaddedforitscontributiontoflavourandcolour.
Oncetheyeasthasbeenaddedtothedoughittakesashortwhilebeforeits
activityissufficientforthegenerationofcarbondioxidegasandthereislittle
changeinthedoughdensity,thisisoftenreferredtoasthelagphase.Ifwe
weretomeasurethedensitychangewithtimeaftermixingwewouldseelittle
changeforsomeminutes.Laterdoughdensitybeginstofallasthecarbondiox-
idegascomesoutofsolutionintheliquidphaseofthedoughandbeginstodif-
fuseintothegasbubblestrappedinthedoughandcausingtheirexpansion.
Typically,thelagphaselastsaround10minutes.Thishaslimitedimpactwhen
bulkfermentationprocesseslastingsomehoursareusedforbreadmakingbutin
no-timedoughproductiontheimpactcanbesignificant.
Themaineffectoftheyeastactivitypostlag-phasewithno-timedough
productionwillbeseeninthedividerandinparticularondividerweight
unusualtoseeadriftintheweightofindividualpieceswithdoughstanding
timeinthehopper.Oneoftheadvantagesgainedfromtheyeastlagphaseis
thatitwilllimitdoughdensitychangesandtherebyimprovedividerweight
control.Thus,inlargerautomatedbakeriesitcanbeofparticularadvantage
tokeepdoughbatchsizeatalevelwhichrequirestheproductionandproces-
singofanindividualbatchofdoughinlessthan10minutesorso(
Cauvain
andYoung,2008
).
References
Boehhout,T.,Robert,V.,2003.YeastsinFoods.WoodheadPublishingLtd,Cambridge,UK.
Cauvain,S.P.,Young,L.S.,2008.BakeryFoodManufactureandQuality:WaterControl&
Effects,seconded.Wiley-Blackwell,Oxford,UK.
RawMaterials
Chapter|2
127
2.6.7Whatdifferenttypesofbakersyeastareavailable?
Wouldtherebeanyparticularadvantagesforustousean
alternativeto
Saccromycescerivisii
inthemanufactureofour
fermentedproducts?
Yeastsuppliershavemanyformsof
S.cerivisii
foruseinthemanufactureof
bakeryproducts.Thecompressedorblockformusedinmanycountriesis
botheconomicalandpractical.Theyeastblocksarepaperwrappedtolimit
exposuretoairandtomaintainhumidityandlimitmoisturemigrationwhich
varyingsizesfromsmallcubesof40guptoblocksof2.5kg.Itcanalsobe
purchasedascrumbledyeast.Itshouldbestoredinarefrigeratorrunningat

C,ideallyaround4

C(see
Section2.6.3
).Theshelf-lifeof
compressedyeastkeptundertheconditionsrecommendedbythesuppliersis
Cauvain(2015)
showedhowstoringhighactivity
compressedyeastat15

Cfor14dayshasareducedactivitytosuchan
extentthatthatprovingtimeofthedoughinwhichitwasusedroughly
doubled.Poorlykeptcompressedyeastquicklydisplaysvisiblesignsof
Section2.6.4
).
Driedandgranulated(
FischerandVolker,2008
)yeastsarepopularwhere
alongershelf-lifeproductisrequiredorwhererefrigerationisnotpractical,
e.g.,inwarmclimates.Itcomesinstandardorinstantdriedforms.The
instantformofdriedyeastisavailableinvacuumpacksandcanbeincorpo-
rateddirectlyintothedough,whereasthestandarddriedyeastneedstobe
hydratedbeforeitisused.Intheirvariousforms,driedyeastshaveshelf-lives
ofupto2years.Someformsofdriedyeastmayalsobeincorporatedinto
premixesforbakeryproducts.
Liquidorcreamyeastisincreasinglypopularinmodernplantbakeries
asitiseasilyaccuratelyandautomaticallydispensedintothemixingbowl.
Itisheldinstoragetankswhicharegentlyagitatedtopreventseparation.In
bakingterms,1.5kgliquidyeastisequivalentto1kgofcompressedyeast
forgasproduction.Theshelf-lifeoftheproductismuchshorterthanthe

C,andthestoragetanks
shouldbecleanedoutonaregularbasistoreducetherisksofcontamination
withunwantedyeasts,mouldsorbacteriawhichmayresultinthedevelop-
mentofsouraromasandflavoursinthedough.
Frozenformsofbakersyeastarealsoavailablefromsomesuppliers.
Theseproductsshouldbestoredat
2
18

Candhaveshelf-livesofupto2years.
Theyareusuallyaddedtothedoughinthefrozenform.
Thedrymattervariesinthedifferentformsofyeastfromapproximately
20%forliquidyeastto95%forthedriedyeast.Ifyouaregoingtochange
fromoneformtoanotherthenthewaterleveladdedtothedoughwillneed
tobeadjustedaccordingtothedrymattercontentofthedifferentforms.
128
BakingProblemsSolved
Therearedifferentstrainsof
S.cerivisii
available,andtheyeastsupplier
willcultivatethesetoofferspecificyeastsfordifferentbakingproductsand
CBPisabletogeneratecarbondioxideatafasterratethanotherstrainsand
avoidsadipingasproductionatthecriticalmomentwhenthedough
piecesreachestheoven(
Cauvain,2015
).Althoughsuchyeaststrainshave
ahighfermentingpower,theytendtobelessstableandhaveashorter
shelf-lifethanotherstrains.
sucroseordextrose),thereareosmo-tolerantyeasts.Theseareabletocope
withtheincreasedosmoticpressureinthedoughratherthanbeinginhibited
bythepresenceofthesugars(
Cauvain,2015
).Therearestrainswhich
Inprinciple,anymicroorganismwhichisabletofermentsugarsto
producecarbondioxidegascouldbeusedinbreadmaking.Therearealarge
numberofyeaststhatwouldfitintothatcategorywhichmaycomefromthe
distillingandwine-makingindustries.Indeedyeastsfromthebrewingand
distillingindustrieswerethetraditionalsourceofgasproductionforbakers.
Improvedgrowth,osmo-tolerance,freeze-toleranceoraromaapplications,
havesuggestedtheuseofstrainsfrom
Candida
or
Torulaspora
.Afewnon-
typicalbakersyeaststrainshavebeenpatentedforcolddoughandnutrition
applicationsandespeciallyforstresstolerance;theseinclude
Saccromyces
rosei
,
Saccromycesrouxii
and
Torulasporadelbrueckii
.
Theavailabilityofstrainsof
S.cerivisii
specificallyforuseinthe
manufactureoffermentedproductsinbakeriesisnowhighlydeveloped,and
discussionswithyoursuppliershouldhelptoidentifythetypeofyeastthat
isthemostappropriateforthemanufactureofyourownproducts.
References
Cauvain,S.P.,2015.TechnologyofBreadmaking,thirded.SpringerPublishingInternational
AG,Switzerland.
Fischer,G.,Volker,L.,2008.Granulatedyeast.f2mBaking
1
BiscuitInternational6,40

43.
Furtherreading
Boekhout,T.,Robert,V.,2003.YeastinFood.WoodheadPublishingLtd,Cambridge,UK.
RawMaterials
Chapter|2
129
2.6.8Whatarethecorrectproportionsofacidsandalkalito
useinbakingpowders?
Theprincipalalkaliusedinbakingpowdersissodiumbicarbonate,anditis
thisingredientthatsuppliesthecarbondioxidegaswhichinflatespowder
raisedgoodssuchascakesandsponges.Forthegastobeevolvedatthe
mostsuitabletimeduringbaking,afoodacidisaddedtotheformulation.
Sodiumbicarbonatewillreleasecarbondioxidebythermaldecomposition
at90
C,butthisisfartoolatetobeofuseinbakingbecausebythat
2.6.9Whatismeantbythetermdouble-actingbaking
powder,andwhatisthevalueofusingsuchproducts?
Double-actingbakingpowdersusuallycompriseamixtureofatleasttwobak-
ingacidsandsodium(orsomeother)bicarbonate.Theoverallcompositionof
thebakingpowderwillbebalancedtakingintoaccounttheneutralisingvalue
ofboththeacidsusedwithrespecttothesodiumbicarbonate.Eachofthe
acidswillhaveadifferentRORandtheintentionistospreadandcontrol
thereleaseofcarbondioxidegasoveranextendedperiodoftimeinthe
bakingprocess.
Double-actingbakingpowdersaremostcommonlyusedinthemanufac-
tureofcakesandareespeciallyusefulinthedeliveryofcarbondioxide
productionintheovenwhichhelpsgivecakesextravolume

almostthe
cakeequivalentofovenspringinbread.Theprocessisshownschematically
in
Fig.2.13
.
Thelevelofsugarsusedinthemanufactureofcakebattersdelaysthe
gelatinisationofthewheatstarch

themainstructureformingagentin
cakes.Thismeansthatcakebattersarefluiduntilrelativelylateonin
thebakingprocess.Althoughthebatterisfluid,itiscapableofexpansion.
Withmanyofthefaster-actingbakingacids,thereleaseofcarbondioxideis
mostlycompletedduringmixingandthefirstfewmomentsofbakingwhich
mayleadtoarestrictionofcakevolumeandatendencyfortheproducts
tohaveapeakedshape.Thisiscommonlyovercomebyincreasingthelevel
ofaddition.
Anotheradvantageofusingadoubleactingbakingpowderisthatthefla-
vouroftheresidualsaltinthebakedcakecanbemodifiedbyusingdifferent
bakingacids.Itisalsopossibletoaidsodiumreductioninbakedproducts
withoutundulycompromisingproductqualitybyusingtwodifferenttypes
ofacidsinthebakingpowder.
Depositing
Release of carbon dioxide
Mixing
Baking
Starch
swelling
Gelatinisation
FIGURE2.13
Thereleaseofcarbondioxidefromdouble-actingbakingpowderincakebaking.
RawMaterials
Chapter|2
131
2.6.10Whyissodiumbicarbonatefrequentlyusedaloneorin
excesstothenormalinbakingpowderfortheproductionof
gingerproducts?
Theideaofusinganexcessofsodiumbicarbonateingingerproductsis
nodoubtbasedontraditionalpracticesrelatedtotheavailabilityofsuitable
chemicalaeratingagents.
Despiteitstraditionalbasis,thepracticedoeshaveapracticaladvantage.
Undertheinfluenceofmoistureandheatcarbondioxideisliberatedfrom
anysodiumbicarbonateleftafterthenormalacid
basereactionandsodium
carbonateremainsasaresidue.Thecarbonateisalkalineandwillreactwith
sugars,particularlyinvertsugartoformcomplexcarboncompoundswhich
arebrownincolour.Inthisway,theexcessofsodiumbicarbonateaidsthe
formationofthedarkbrowncolourwhichcharacterisesgingerproducts.
Ifyoulookcloselyatthecutsurfaceofbakedgingercakes,youmay
seethatthecolourismoreintensetowardthebaseandsidesofthecross-
section.Thesearetheareaswhicharebakedfirstandsohavebeenheld
foralongertimeattheoventemperature,andthebrowningreactionhas
proceededfurtherthanthemoistercentreareasofthecake.
Theresidualsodiumcarbonatehasacharacteristicwashingsodataste
whichiswhywenormallyseektoneutralisethesodiumbicarbonateinmost
bakedproducts.However,thestrongflavourofgingerwillcommonlymask
someofthecarbonateafter-taste.
BakingProblemsSolved
2.7IMPROVERS
2.7.1Whatarebreadimproversandwhyaretheyused?
Thetermbreadimproverisusedtoembraceawiderangeofmaterials
whichcanbeaddedtowheatflouranddoughtoimprovesomeaspectof
doughbehaviourandfinalbreadquality.Theuseofthetermiscommonand
mostoftenappliedtotheadditionofseveralingredientsatlowlevels
blendedwithacarrier,amaterialwhichmayormaynothavefunctional
propertiesbutwhichaidsdispersionandprovidesamoreconveniently
handledcompositematerial.Theformulationofbreadimproverswillbe
influencedbylegislativecontroloverthelistofpermittedingredientswhich
maybeusedinbreadmaking.
Alternativenamesforbreadimproverswhichmaybeencounteredinthe
bakingindustryinclude:
Doughconditioners
,aspecificreferencetothefactthatthematerial
additionchangesdoughrheology.
Processingaids
,whichimpliesasimilarfunctiontodoughconditioners.
Oxidisingagents
,whichimpliesamorespecificroleconcernedwiththe
Someofthemorecommoningredientsusedinbreadimproversare
notedbelow.Theclassificationusedisarbitrarysincethecomplexactions
ofmostmaterialsinbreadmakingmeansthattheymightbeclassifiedin
morethanonegroup.Forexample,theadditionofenzymepreparations
bringsaboutchangesindoughrheologywhichmakesiteasiertoprocess
doughsbutalsoresultsinimprovedovenspring,amanifestationofimproved
gasretention.
Aidstodoughprocessing.
Enzymeactivepreparations,e.g.,maltflour,proteolyticenzymes.
Reducingagents.
RawMaterials
Chapter|2

Aidstogasproduction.

Yeastfoods,suchasammoniumchloride.


Oxidisingagents,suchasAAandpotassiumbromate.

Enzymeactivematerials.

Emulsifiers.

Aidstobreadsoftness.

GMSandotheremulsifiers.

Enzymeactivematerials.

Aidstoimprovingcrumbcolour.

Soya(soy)flour.
Furtherreading
Cauvain,S.P.,2015.TechnologyofBreadmaking,thirded.SpringerInternationalPublishing
AG,Switzerland.
134
BakingProblemsSolved
breadimprovers?Whatconsiderationshouldwetakeinto
accountwhenchoosingwhichonetouse?
Thereisnoprecisedefinitionoftheseterms.Itcouldbearguedthattheterm
doughconditionercouldincludetheuseofmaterialstomodifyanydough-
basedproductwhichwouldincludebread,biscuitandpastrydoughs,whereas
thetermbreadimproversuggeststhatanyeffectsareconfinedexclusivelyto
breadandfermentedproducts.However,inpractice,bothtermsarecommonly
usedinterchangeablyandthiscancreatesomeconfusion.
Bothtermsareusedtodescribeafunctionalingredientoramixtureof
functionalingredientswhichareaddedatlowlevelstobeneficiallymodify
oneormorecharacteristicsofthefinalqualitiesofbreadandfermentedpro-
ductsortheirprocessingintermediaries,i.e.,thedough.Alloftheingredients
whichwouldfallintothiscategorywillmodifyfinalproductqualities,and
thevastmajoritywillalsomodifytherheologicalpropertiesofthedough.In
anumberofcases,itisthemodificationofthedoughrheologywhichdeli-
verstheimprovementtothefinalproduct.
Thecompositionsofdoughconditionersandbreadimproversarecompli-
catedandvariedaccordingtotheparticularbreadproductbeingmadeand
processesusedtomakethem.Theymayalsovarywithtimeastheformula-
tionsareadaptedtochangingrawmaterialinputs,suchasanychangesin
wheatandflourqualityfromoneharvestyeartothenext,andtolegislative
andconsumerpressures.
Whenyouareconsideringwhichdoughconditionerorbreadimproverto
use,youshouldconsiderfirstwhatqualitychangesyouwishtoeffectand
thenidentifywhichfunctionalingredientwilldeliverthosequalitychanges
thatyouareseeking.
Examplesofimprovementcategoriesandthefunctionalingredients
whichcontributetothoseimprovementsincludethefollowing:

Improveddoughprocessing

Enzymesandreducingagents(e.g.,
L
-cysteinehydrochloride,see
Section2.7.8
).

Improvedproductvolume

Oxidants(e.g.,AA),emulsifiers,enzymes.

Improvedcellstructure

Oxidants.

Improvedcrumbsoftness

Emulsifiers,enzymes.

Extendedproductshelf-life

Emulsifiers,enzymes.

Increasedmould-freeshelf-life

Preservatives.
Theindividualingredientsthatyouwillbeabletochoosefromwill
begovernedbylocallegislationandyoushouldcheckcarefullyastowhatis
permittedforyourcountry.
RawMaterials
Chapter|2
135
2.7.3Whatarethefunctionsofascorbicacidinbreadmaking?
AAiscommonlyknownasvitaminCandispresentinlargequantitiesin
patent(BP455,221)existingfrom1936.Itisacommonlyusedoxidant
(improver,additive),andinmanycases(e.g.,withintheEuropeanUnion),
itistheonlyonepermittedforuseinbreadmaking.
effectontheglutenstructure.Intermsofitschemistry,AAisareducing
mixing,itisreadilyconvertedtoDHA(see
Fig.2.14
)inthepresenceof
oxygenandascorbicoxidaseenzyme.Theoxygenfortheconversioncomes
fromthegasbubblesincorporatedduringdoughmixingandtheconversion
isenabledbytheascorbicoxidaseenzymeoccursnaturallyinwheatflour.
ThechemistryoftheAAoxidationprocessindoughmixingiscomplex
(
Cauvain,2015
)butprobablyinvolvestheoxidationofthe
s
S
s
H(sulphydryl)
groupsofgluten-formingproteinsandtheformationof
s
S
s
S
s
(disulphide)
bonds.ThenetresultoftheAAeffectistoimprovetheabilityofthedough
toretaingas(asseenbyincreasedovenspring)andtoyieldbreadwitha
finer(smalleraveragecellsize)crumbcellstructure.Thesechangesalso
resultinbreadcrumbwhichissoftertothetouchyethastheresiliencyto
recovermuchofitsoriginalshapeaftercompression.Thishelpstoconveythe
impressionofimprovedfreshnesstotheconsumer.
ThedependencyonoxygenfortheAAtoDHAconversionmeansthat
thequantitiesofairincorporatedduringdoughmixingplayasignificantrole
inpromotingoxidation.ThismeansthatAA-assistedoxidationvarieswith
mixertypeduetotheabilityofdifferentmixerstooccludedifferentquanti-
tiesofair(
Cauvain,2015
).Somemixingregimeshavebeendeveloped
whichincreasethetotalquantityofairoccludedduringmixingsothat
greaterAA-assistedoxidationcanbeachieved;twoexamplesaremixing
inanoxygenenrichedatmosphereandtheuseoftheso-calledpressure-
vacuummixer(
Cauvain,2015
).Therehasbeenatendencytoconsiderthat
itisnotpossibletoover-treatwithAAduetothelimitingeffectassociated
FIGURE2.14
Ascorbicacidchangesindough.
136
BakingProblemsSolved
withoxygenavailability.Withtheadventofthepressure

vacuummixer,
suchstatementsshouldbeviewedwithcaution.
TheoxidisingeffectofAAismainlylimitedtothedoughmixingperiod
becausebakersyeastwillremoveanyoxygenremainingintheairbubbles
bytheendofmixingorsoonafteritscompletion.Thus,inthedoughwhich
leavesthemixer,thegaseousmixtureofnitrogen(fromtheair)andcarbon
dioxide(fromyeastfermentation)whichremainsprovidesanenvironment
inwhichAAcanactasareducingagent.IfAAisusedindoughmakingpro-
cesseswithextendedperiodsoffermentation,thentheopportunityexistsfor
thereducingeffectofAAtoweakentheglutenstructurewithsubsequent
makingsystems.
TheactionofAAduringmixingalsobringsaboutchangesintherheol-
ogyofthedoughmakingitmoreresistanttodeformationbycomparisonwith
doughstreatedwithanadditionofpotassiumbromatewhichdoesnotexert
itsfulleffectuntilthedoughreachesthelatestagesofproofandtheearly
stagesofbaking.
Reference
Cauvain,S.P.,2015.TechnologyofBreadmaking,thirded.SpringerInternationalPublishing
AG,Switzerland.
RawMaterials
Chapter|2
137
2.7.4Wehaveheardthatsoyaflourisaddedinbreadmakingto
makethebreadwhiter.Isthistrue,andifsohowdoesitwork?
Full-fat,enzymeactivesoyaflourhascommonlybeenusedasafunctional
ingredient(improver)inbreadmakingsincethe1930s.Itisoftenused
asacarrierforotherfunctionalingredients,e.g.,oxidants,tofacilitatethe
additionofthesmallquantitiesthatarecommonlyused.Thesoyabean
containsahighpercentageofnaturaloilandhasadistinctivebeany
flavourwhichcanbeunpleasantifusedathighlevelsofadditionbutnotat
the1or2%levelnormallyusedwithbreadimprovers.
Soyaflourthreebasicfunctions;itgivesawhitebreadcrumb,itcontri-
whichneedstobeaddedtothedough.Thefirsttwofunctionsarecausedby
theactionsofthenaturalenzymesystemswhicharepresent,andsoitis
importantthattheenzymeactiveformofsoyaflourisused.
Soyaflourisrichintheenzymelipoxygenasewhichplaysamajor
roleinitsbleachingaction.Withthehelpoftheenzyme,theintermediate
oxidationcompoundsformedduringdoughmixingtransferoxygenfromthe
atmospheretobleachtheyellow-colouredcarotinoidpigmentspresentin
theflour.Bythismechanism,theflourisbleachedandthebreadcrumb
becomeswhiter.Thegreatertheavailabilityofoxygenthegreaterthebleaching
effect.
Theoxidationeffectappearstocomefromfreeingofboundlipidsfrom
specificsectionsoftheglutenproteinstherebyallowingtheproteinsto
becomehydrophillicandhelpingtoformthevisco-elasticsurfaceoftheair
bubblesinthedough(
).
Soyaflouranditsderivativeshavefoundotherusesinbaking,including
asaneggreplacerandingluten-freebreads(
Cauvain,2015
).Thereare
someconcernswithrespecttosoyaallergies.
References
Cauvain,S.P.,2015.TechnologyofBreadmaking,thirded.SpringerPublishingInternational
AG,Switzerland.
onthemechanicaldevelopmentofwheatflourdoughs.J.Sci.FoodAgric.24(4),421

436.
138
BakingProblemsSolved
2.7.5Iunderstandthatanenzymecalled
alpha
-amylasecanbe
addedtoflourordoughtoimprovebreadqualitybutthatthere
effectsonbreadsoftness.Whichone(s)shouldIuse?
The
alpha
-amylasesareagroupofenzymeswhichfacilitatethebreaking
downofthehydratedstarchgranules,bothamyloseandamylopectin,inflour
doughsintoshorterchained,unbranchedmoleculesknownasdextrins.
Thisactioncreatessitesforthe
-amylasewhichispresentinwheatflour
toconvertthestarchtoindividualmaltosemolecules.Wheatfloursusually
containsufficient
-amylasebutlevelsof
alpha
-amylasevaryandin
manycasesmaybesolowthatthestarchtomaltoseconversionislimited.
Aspartoftheamylaseactionswatermoleculeswhichwerepreviouslyheld
withthedamagedstarchgranulesmaybereleasedintothedoughmatrix.
Maltoseisfermentedbybakersyeasttoprovidecarbondioxidegas
inthedough,andthus,akeyrolefor
alpha
-amylaseistosupportgaspro-
duction.Althoughthiswastheoriginalreasonbehindtheadditionof
sourcesof
alpha
-amylasetowheatflourdoughs;inmanycases,itsaddition
(
CauvainandChamberlain,1988
),andthishasnowbecomethemain
reasonforitsaddition.
Thetraditionalsourceof
alpha
-amylaseforbreadmakingwasfrom
maltedbarleyorwheatflour,buttoday,itismorecommontouseamylases
derivedfromthefermentationofmicroscopicfungi(e.g.,
Aspergillusoryzae
)
theirheatstabilities(
Cauvain,2015
).Themoreheatstabletheamylasethe
greaterthebreakdownofthestarchduringbaking.Ingeneralterms,fungal
alpha
-amylaseisinactivatedbeforecereal(malt)which,inturn,isinacti-
vatedbeforebacterial.Theso-calledmaltogenicamylasesarederivedfrom
modifiedbacterialsourcesandhaveaprofilemoresimilartothatofthe
fungalsource.
Theheatstabilityoftheamylasesource(see
Fig.2.15
)isimportantin
theamylaseattacksthedamagedstarchgranulesandbreaksdownthestarch
molecules.Asheatingproceeds,especiallyduringbaking,theswellingand
latergelatinisingstarchprovidesalargerquantityofavailablesubstratefor
theamylaseenzymeswhicharenowworkingatafasterrateduetothehigh-
relatedtotheformationofstickydextrins(seealso
Section4.1.35
).
Tomaximisethebenefits,youshouldusethefungalsource.Themalto-
genicformcanbeusedduetoitsgreateranti-stalingeffectwhichgives
RawMaterials
Chapter|2
139
softerbread.However,ifusedattoohighalevel,youmayfinddifficulties
inslicingthebreadduetoitsenhancedinitialsoftness.Avoidusingthetra-
ditionalbacterialformasthismaysurvivethebakingprocessandleadto
unwantedliquificationoftheproductcrumbduringstorage.
References
Cauvain,S.P.,2015.TechnologyofBreadmaking,thirded.SpringerPublishingInternational
AG,Switzerland.
Cauvain,S.P.,Chamberlain,N.,1988.Thebreadimprovingeffectoffungal
alpha
-amylase.
J.CerealSci.8(Nov),239

248.
FIGURE2.15
Effectoftemperatureon
alpha
-amylaseactivity.
140
BakingProblemsSolved
2.7.6Whyareemulsifiersusedinbreadimprovers?Andhow
doIdecidewhichoneIshouldbeusing?
Emulsifiersareusedinbreadimproversforanumberofdifferentreasons
including:

tohelpcontrolgasbubblesize,


toimprovedoughstabilityand

toimprovecrumbsoftness.
Eachoftheemulsifierspermittedforuseinbreadmakingcontributes
degreesdependingontheparticularemulsifier.
Themostcommonlyusedemulsifiersandtheirlikelycontributionto
doughcharacterandbreadqualityareasfollows:

(DATAesters,DATEM)
.Theyarethoughttoreducetheaveragegasbub-
blesizeinbreaddoughswhichleadstoafinercellstructure.Theyare
breadvolumeandcrumbsoftness.Levelsofadditionareusuallyupto

Sodiumsteoryl-2-lactylate(SSL)
volumeandcrumbsoftnessbutweightforweightislesseffectivethan
tedproducts,e.g.,bunsanddoughnuts.

Glycerolmonostearate(GMS)
.Bestusedinthehydratedformbutcanbe
addedasapowder.Doesnotgreatlycontributetodoughgasretentionof
breadvolumebutdoesactacrumbsoftenerthroughitsprovenanti-staling
effect.

Lecithins
.Agroupofnaturallyoccurring,complexphospholipidscommonly
derivedfromsoya.Usedinbaguetteandothercrustybreadstheydoimprove
doughgasretentiontoadegreeandcontributetocrustformation.
Asnosingleemulsifierwillequallyperformallofthetasksrequired
inbreadmaking,itbecomesacaseofchoosingagivenemulsifiertofitwith
themainproductandprocessrequirements.Orablendofemulsifiersmaybe
used.Pricemayalsoinfluenceyourfinalchoice.
Furtherreading
Cauvain,S.P.,2015.TechnologyofBreadmaking,thirded.SpringerPublishingInternational
AG,Switzerland.
Whitehurst,R.J.,2004.EmulsifiersinFoodTechnology.BlackwellPublishing,Oxford,UK.
RawMaterials
Chapter|2
141
2.7.7Whatis
L
-cysteinehydrochloride,andwhatisitusedfor
inbreadimprovers?
Cysteineisanaturallyoccurringaminoacidduetoitssulphydrylgroup
(
s
S
s
H)isabletoactasareducingagentonthedisulphide(
s
S
s
S
s
)bonds
presentintheglutenstructureofwheatflourdoughs.Itismostcommonly
usedinthehydrochlorideformtoimproveitssolubility.
Itcameintocommonuseinbreadmakinginthe1960swhenitwasakey
componentofthebreadmakingprocesswhichbecameknownasactivated
doughdevelopment(ADD)(
Cauvain,2015
).InADD,
L
-cysteinehydrochlo-
ridewascombinedwithpotassiumbromateandAAtogiveanimprover
capableofdeliveringbothchemicalreductionandoxidationprocessesduring
doughmaking.ADDwasdesignedtoallowbakerstoobtainthebenefitsof
makingno-timedoughswithouttheneedforthehigh-speedmixersassoci-
atedwiththeCBP.ADDremainedverypopularwithsmallerbakersuntil
supersededbytheuseofspiralmixers(
Brown,1993;Cauvain,2015
).
Insomeways,thechemicalreductionofglutendisulphidebondsby
L
-cysteinehydrochloridecanbeequatedtothemechanicaldisruptionofsuch
bondsintheCBP.Thisviewhasledtotheconsiderationthatoneofthe
benefitsderivedfromtheuseof
L
-cysteinehydrochlorideisthatworklevels
canbereducedintheCBP.
Morecertainisthatthereducingeffectsof
L
-cysteinehydrochloridebene-
ficiallymodifydoughrheologyandimproveitsprocessingperformance.For
example,itsadditiontoso-calledbuckydoughsintheUSA(i.e.,doughs
havinghighresistanceandlackingextensibility)improvesdoughmoulding,
andintheCBP,steaksandswirlsinthecrumbmaybereduced,butnot
eliminated(
Cauvain,2015
).
Additionsof
L
-cysteinehydrochloridemaybemadetofermentedpro-
toreducedoughandproductshrinkage.
References
Brown,J.,1993.Advancesinbreadmakingtechnology.In:Kamel,B.S.,Stauffer,C.E.(Eds.),
AdvancesinBakingTechnology.BlackieAcademic&Professional,London,UK.
Cauvain,S.P.,2015.TechnologyofBreadmaking,thirded.SpringerPublishingInternational
AG,Switzerland.
142
BakingProblemsSolved
2.7.8Canweaddareducingagentduringdoughmakingsothat
wecanreducetheenergyinputrequiredduringthemixing?
Theinputofenergyduringmixingisanessentialpartofthedevelopmentofthe
glutenstructure;however,thisenergyinputisaccompaniedbyanincreasein
thetemperatureofthecombinedingredients.Thistemperatureriseincreasesas
thelevelofenergyinputincreases,therelationshipisessentiallylinear.
Optimumdevelopmentiscommonlyassociatedwithenergyinput,in
someprocess(e.g.,theCBP).Thismaybetoadefinedtotalenergylevel,
thoughinmostcasesitequatestothelengthofmixingtime.Fortheretobe
atransferofenergy,thedoughingredients,astheycombinetoformadough,
mustresistthemovementoftheimpellerblade.Toovercometheresistance
ofthedoughthework(energy)requiredbythemixermotorincreases,and
ofcoursesodoesthedoughtemperature.
Reducingagents,whenaddedtodough(andpastes),interactwiththe
disulphidebondswhichareacomponentofglutendevelopment.Inessence,
theyreduceorbreakthebondswhichweakenthedoughandlowerits
resistancetodeformationduringmixing.Inthisway,theenergyinputis
loweredandwithitthetemperaturerises.
Inthiscontext,theadditionofareducingagentmaybeseenashavinga
Chapter|2
2.7.9Whatisdeactivatedyeastandhowisitused?
Inessencedeactivatedyeastcomprisesthecontentsoftheyeastcellwithout
theintegrityofthecellitself.Innormalyeastcellsthevariousenzymes
andnaturalchemicalswhicharerequiredforcellactivityarecontained
withinthecellwall.Thiscellwallormembraneisresponsibleforcontrol-
lingtheflowofnutrientsintothecellwhicharerequiredforreproductionof
thecells.Theflowoftheby-productsoffermentation
typicallycarbon
dioxideandalcohol
outofthecellisalsocontrolledbythecellwall
membrane.
Awiderangeofenzymesandnaturalchemicalsarecontainedwithinthe
yeastandtheiractivityisnotdependentontheintegrityofthecells.Inthe
contextofdeactivatedyeastthebiasistowardsthosematerialswhichhave
animpactontherheologicalpropertiesofthegluten
formingpropertiesof
thewheatproteins.Specifically,deactivatedyeastiscommonlyusedforits
reducingeffectonglutenandsointhiscontextisseenasanaturalalterna-
tivetootherchemicalreducingagentsinthemanufactureofbreadandother
bakedproducts.
Twokeygroupsofactivatematerialswhichareimplicatedinthe
reducingeffectsareproteolyticenzymesandgluthothione.Tosomeextent,
thetermdeactivatedismisleadingasthenaturallyoccurringreducing
agentsremainactiveinthechemicalsense.Thetermreferstothelack
ofgas-producingcapabilitiesintheyeast,inpartbecausethecellwall
Chapter3
Ingredients,RecipesandBaked
ProductQualities
3.1INTRODUCTION
Examplesoftheimportantcontributionsthattheprimaryrawmaterialsmake
tobakeryproductqualitieshavealreadybeenshownin
Chapter2
,Raw
Materials;however,thesuccessfulmanufactureofbakeryproductsandopti-
misationoftheirqualitiesareonlyachievedbyanunderstandingofthekey
ingredient

bakeryproductsapartfromthemanufactureofmanybakeryfoods(
Cauvain
andYoung,2006
).Inthiscontext,thequalitymodelswhichareapplicable
basisoftheuseofwheatflourandthemanagementofthedevelopmentofa
context,
CauvainandYoung(2006)
havehighlightedthekeyroleplayedby
thepresenceandlevelsofsugarandfatinbakeryproductrecipes,butthere
aremanyotheringredient,recipeandprocessfactorswhichwillinfluence
theendproductresult,andnocomprehensivebakerytreatisecanidentify
andenumerateallofthepotentialinfluencesinvolved.Thischapteraimsto
illustratehowanunderstandingofthecomplexingredient

recipe-process
interactionsprovidesthebasisofthesolutionswhichareofferedtothevari-
ousproblemsandanswerstothequestionwhicharediscussedinthesubse-
quentchapters.Whileaddressingthisaim,theconceptofrecipebalance
willbeidentified,discussedandillustratetheprincipleswiththehelpofa
fewexamples.Inthefollowingdiscussion,recipebalanceisconsideredtobe
morethantheratioofingredientstooneanother.Theseareveryimportant
buttheymustbeplacedintheprocesscontexttofullyunderstandhowto
manipulateendproductquality.Asalreadydiscussed,suitablemathematical
modelsforthemanufactureofbakeryproductsarelimited,andinpractice,
manybakersuseintuitiveruleswhichhavebeenpassedonorlearntthrough
trialanderror.
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2017ElsevierLtd.Allrightsreserved.
Asdiscussedin
Chapter1
,IntroductiontoProblemSolvingTechniques,
onepossibleroutetooptimisebakeryproductqualityliesintheabilityto
breakproblemsdowninamannerwhichallowsthecriticalfactorstobeiden-
tifiedandtoprovideabasisforqualityoptimisation.Inthefollowingsections,
someguidelinesareofferedforthemajorbakeryproductgroupswiththeaim
ofprovidingsummariesofsomekeyingredientsandprocessfactorswhich
affectfinalproductqualitiesonthebasisofspecificproductcharacteristics.In
theexampleswhicharegivensomekeyinteractionsbetweeningredients,rec-
ipeandprocessareidentifiedtoillustratehowreaderscandeveloptheirown
personaliseddatabases,checklists,knowledgefragmentsandknowledgetrees.
3.2STRUCTUREOFBREADANDFERMENTED
PRODUCTRECIPES
Itremainsacommonpracticeforbreadandfermentedproductsrecipestobe
structuredusingflourastheingredientagainstwhichotheringredientratios
Chapter1
,IntroductiontoProblemSolvingTechniques.Inessence,itisthe
bakersattempttobalancetheratiosofingredientsonthebasisoffunctional-
ity.Therearenospecificrulesforbalancingbreadandfermentedproduct
recipesthoughkeyrelationshipswillinvolvetheadjustmentofrecipewater
leveltotakeintoaccountvariationsinflourcharacteristics(see
Section2.2.3
)
mentationprocesses.Breadandfermentedproductrecipesvaryconsiderably
ferences(
Cauvain,2015
)sothatvariationsinwhatconstitutesabreadrecipe
aretobeexpected.However,thereissignificantcommonalityintheingre-
dient

recipe-processinteractions,andtheirultimateinfluenceonproduct
qualitytowarrantidentificationofsomeofthekeyrelationships.
3.3SOMEKEYRELATIONSHIPSINTHEMANUFACTUREOF
BREADANDFERMENTEDPRODUCTS
Theprimaryfactorswhichunderpinthemanufactureofbreadandother
fermentedproductscanbeidentifiedunderthefollowingheadings:

Cellcreation

Gasproduction


Doughdevelopment

Doughrheology
Allthefiveprimaryfactorsmakesignificantcontributionstofinalproduct
qualities,asdiscussedbelow,andareprofoundlyinfluencedbytheidentified
examplesofrecipebalanceandprocessfactors.Readersshouldnotecombina-
tionsoffactorsmaycontributetomorethanoneproductcharacteristic.
146
BakingProblemsSolved

Positiveinputofflourproteinsandthenegativeinputofash(bran).

Recipewaterlevelsbasedonflourpropertiesandinputsfromother
ingredients.

Levelofflourproteinandtheinputofmechanicalenergyduringmixing.

Levelofrecipeyeast,doughtemperatureandfermentationtime.

Improverlevel,compositionanddoughtemperature.

Inputsfromfinalprovertemperature,humidityandtime.

Recipewaterlevelsbasedonflourpropertiesandinputsfromother
ingredients.

Levelofflourproteinandtheinputofmechanicalenergyduringmixing.

Levelofrecipeyeast,doughtemperatureandfermentationtime.

Improverlevel,compositionanddoughtemperature.

Finalprovertemperature,humidityandtime.

Doughpiecedimensionsandoventemperature.

Recipesugarlevelsandoventemperature.

Doughenzymicactivityandfermentationtimeandtemperature.

Levelofrecipeyeast,doughtemperatureandfermentationtime.

Recipewaterlevelsbasedonflourpropertiesandinputsfromother
ingredients.

Ascorbicacidassistedoxidationandtheavailabilityofoxygenfromthe
actionofthechosenmixer.

Doughtemperature,yeastlevelandprocessingtime.
3.4STRUCTUREOFLAMINATEDPRODUCTRECIPES
Thekeyrelationshipsinlaminatedproductrecipesrevolvearoundtherela-
recipesforlaminatedproductarerelativelystraightforward,andaswith
breaddough,themainingredientratiosarethoseofwatertoflour,withother
ingredientadditionscoveringawiderangeoflargelyindividualpreferences.
Itislargelytheratiooflaminatingfattobasedoughwhichcharacterises
laminatedproducts(see
Section7.1.11
)thoughthereisalsoanimportant
interactionwiththeleveloflaminationtobetakenintoaccount(
Cauvain,
2001
).Withfewotheringredientstoconsider,thestructureoflaminatedpro-
ductsisrelativelysimpleandtherearenomajorrulesofrecipebalanceto
consider.
Chapter|3
147
3.5SOMEKEYRELATIONSHIPSINTHEMANUFACTURE
OFLAMINATEDPRODUCTS
Theprimaryfactorswhichunderpinthemanufactureoflaminatedproducts
areverysimilartothoseforbreadmaking,inpartbecauseoftheneedfora
degreeofglutendevelopmenttoforitsimpactonproductliftandstructure.
Theprimaryfactorsmaybesummarisedasfollows:

Doughdevelopment

Pasterheology


Gasproduction
Inthecaseoflaminatedproduct,pasterheologyisespeciallyimportant
productgroupisalsoassociatedwithlayerintegritysothatsteampressureis
Section7.1.1
).Gasproduction
mostlyreferstothemanufactureofyeast-raisedlaminatedproductslike
croissantandDanishpastries.

Flourcharacteristicsandprocessingconditions.

Energyinputduringmixing,numbersoflaminationsandlengthofresting
periods.

Laminatingfatcharacteristicsandprocessingtemperature.

Flourcharacteristicsandprocessingconditions

Energyinputduringmixing,numbersoflaminationsandlengthofresting
periods.

Flourcharacteristicsandprocessingconditions.

Energyinputduringmixing,numbersoflaminationsandlengthofresting
periods.

Laminatingfatlevelandnumbersoflaminations.

Laminatingfatlevelandqualitycharacteristics.

Laminatingfatlevelandnumbersoflaminations.
3.6STRUCTUREOFSHORTCRUSTPRODUCTRECIPES
Shortcrustpastryrecipesarecharacterisedbywhethertheyareforthemanu-
theadditionofsugarstotherecipe.Therearenosignificantrulesofrecipe
148
BakingProblemsSolved
balanceforshortcrustpastryproductsotherthantheconsiderationthatthe
higherthelevelofrecipefattheshortertheeatingqualityoftheproductis
likelytobe.Thiseffectisbasedontheinhibitionofglutenformationbythe
employedformixingthepaste(
CauvainandYoung,2006
).
3.7SOMEKEYRELATIONSHIPSINTHEMANUFACTURE
OFSHORTCRUSTPASTRIES
Themain,ifnottheonlyprimaryfactorassociatedwithshortcrustpastry
production,ispasterheology,andwhilerecipewaterleveldoesplayarole
ofsugarislimited.

Flourcharacteristicsandprocessingconditions.

Levelandtypeofrecipefatandprocessingconditions.

Recipewater,fatandsugarlevels,mixingandprocessingconditions.
3.8CAKES

HIGH-ANDLOW-RATIORECIPES
Intheconstructionofcakerecipes,itistraditionaltousetheflourasabase
onwhichtodeterminethelevelsoftheotheringredientsbeingused.The
classicalconstructionofcakerecipesisbasedonthefunctionalityoftheindi-
vidualingredientsandtheircontributiontothedevelopmentofacakestruc-
ture.Inthisrespect,akeyroleisplayedbythelevelofsugarintherecipeas
thisingredienthasasignificanteffectonthegelatinisationcharacteristicsof
thestarchinthewheatflour.Asstarchisthemainbuildingblockofthe
cakestructure,anychangestoitsgelatinisationcharacteristicswillhavea
significanteffectoncakequality.Theadditionofsugarinacakereciperaises
thecakestructure(thefoamtospongeconversion).
Theotherkeyingredientincontrollingthegelatinisationcharacteristics
ofstarchiswater.Thelevelofwaterintherecipeisimportantfordissolving
thesugarandprovidingmoistureforthestarchgranulestohydrate,swell
andultimatelygelatinise.Empiricalworkhasshownthatasucroseconcen-
trationofaround0.5deliversacceptablecakequality(
CauvainandYoung,
2008
waterlevelsusedinacakerecipe.
Thetermslow-andhigh-ratioareusedtodefinetherecipetypesusedin
thisisreferredtoasliquidwhichisthesumofingredientssuchaseggor
Chapter|3
149
milk,butonlythewatercomponentoftheseingredientsshouldbeconsid-
ered)intherecipeareindividuallylowerthanthelevelofflour,whereas
high-ratioimpliesthattheyareindividuallygreaterthantheflourweight.
Fortheflourtobeabletosupportahigherlevelofsugarandliquid,itis
necessaryforittohavebeentreatedinsomeway;suchtreatmentmaybe
withchlorinegas(see
Section2.2.18
)orwithdryheattreatment(see
Section
2.2.17
).Inaddition,thereisatendencyforhigh-ratiorecipestousefatin
whichanemulsifierhasbeenaddedtoaidbatteraerationandstability.
Theexternalcharacteristicsofhigh-andlow-ratiocakesappearverysim-
ilar,andinternally,thehigh-ratioproducttendstohaveafinerandmoreuni-
formtexture(see
Fig.3.1
).However,whenitcomestoassessingthecrumb
characteristicsofthetwoproducts,thehigh-ratiocakeproductsexhibitsofter
andmoretendereatingproperties.Inpart,thiscomesfromthehighermois-
turelevelwhichusuallyremainsinthebakedhigh-ratioproducts;typically,
thiswillbeintheorderof3

6%higher(
CauvainandYoung,2006
).
Thekeycharacteristicsoflow-andhigh-ratiorecipesmaybesummarised
asfollows:
IngredientLowratioHighratio
FlourtreatmentNoneDryheat(orchlorinegas)
SugarEqualtoorlessthanthe
flourweight
Greaterthanthe
flourweight
Water(from
allsources)
Equaltoorlessthanthe
flourweight
Greaterthanthe
flourweight
FattypeNospecialformFatwithemulsifier
3.9CAKESANDSPONGES

THEROLEOFRECIPEBALANCE
Inthecaseofcakemanufacture,therearesomeempiricalruleswhichhave
evolvedtoconsiderthebalanceofingredientsinarecipewithrespect
(e.g.,
BennionandStewart,1958
),andtherulescommonlydatetoaperiod
FIGURE3.1
Comparisonof(left)high-and(right)low-ratiocakes.
150
BakingProblemsSolved
ontimewhencakeproductionwasbeinginfluencedbytheintroductionof
so-calledhigh-ratiorecipesbasedontheuseofchlorinatedflour.
Therulesofcakemakingmaybesummarisedasfollows:
Theratioofsugartoflouristhefirstrulethatisconsidered,andthisis
commonlydefinedonthebasisofwhethertherecipeisloworhigh
ratio(seeabove).
Theeggandfatslevelsareusuallybalancedagainstoneanother.This
ruleisrelatedtotheimpactofthesetwoingredientsontheeatingquali-
tiesofthefinalproducts;eggproteinimpartsafirming/tougheningeffect
ontheeatingqualitywhilefatdeliverstenderness.
Oncethelevelofegghasbeendecided,itisnecessarytochoosethefinal
liquidlevelintherecipe.Thisshouldbebalancedwiththesugarlevelto
deliverasuitablesucroseconcentrationinthebatter(seeabove).The
liquidsshouldincludetheegg,milk(ifusedasliquidmilk)andwater.
Youwillneedtobesurethatyouhaveidentifiedallsourcesofwater.
Althoughyoucanworkwiththeliquidsintheiraddedform,youmay
finditmoreusefultoseparateoutthewaterfromeggandmilkwhen
doingyourcalculations.
Chapter|3
quality.Cellcreationandgasproductionremainaskeyfactorsandbatter
viscositymaybeconsideredascomparablewithdoughrheology.

Recipeingredients.

Levelandtypeofbakingpowder.

Mechanicalandchemicalaeration.

Recipeingredients.

Mechanicalandchemicalaerationandheatinputduringbaking.

Recipesugarlevelsandoventemperature.

Mechanicalandchemicalaerationandheatinputduringbaking.
References
Bennion,E.B.,Stewart,J.,1958.CakeMaking,thirded.LeonardHill[Books]Limited,London,
UK.
Cauvain,S.P.,2001.Theproductionoflaminatedbakeryproducts.CCRAReviewNo.25.
CampdenBRI,ChippingCampden,UK.
Cauvain,S.P.,2015.TechnologyofBreadmaking,thirded.SpringerPublishingInternational
AG,Switzerland.
Cauvain,S.P.,Young,L.S.,2006.BakedProducts:Science,TechnologyandPractice.Blackwell
Publishing,Oxford,UK.
Cauvain,S.P.,Young,L.S.,2008.BakeryFoodManufactureandQuality:WaterControl&
Effects,seconded.Wiley-Blackwell,Oxford,UK.
152
BakingProblemsSolved
Chapter4
BreadandOtherFermented
Products
4.1BREAD
4.1.1Weareproducingarangeofpanbreads,somebaked
inarackovenandothersinadeckoven,andfindthatthereare
largeindentsorcavitiesinthebaseofmanyoftheloaves.
Whatisthecauseofthiseffectandhowcanitbeovercome?
Whenthepansentertheovendoughexpandstotouchallofthesides
ofthepan.Asthetemperaturecontinuestorise,thedoughpiececan
nolongerexpandoutwardsduetothepansidesandsostartstogrow
upwards.
expandingdough,thedoughwillcontinuetomoveupwardsuntilthetemper-
atureconditionsagainstthepansidesaresuitablefortheformationofthe
sideandbottomcrustoftheloaf.Thisnormallyhappensfairlyquicklydue
whichhasbeenlostfromthehotdoughbeginstodiffuseupthesideofthe
pansandisnormallylosttotheatmosphere.
Thecentreofthedoughcontinuestoexpandafterthebottomcrusthas
formedsothatdoughbecomescompressedagainstthesidesoftheforming
loaf.Insomecases,thisextracompressioncausesastrongsealtoform
canbecomesogreatthatareasofthebakingdoughmaybeforcedaway
fromthepansidesandbaseandthecavitiesorlargedentsthatyouseeare
formed(see
Fig.4.1
).
Thesimplestsolutiontotheproblemistousepanswithsmallholes
drilledattheanglewherethebaseofthepanjoinsthesidewalls.Itisusually
eachofthetwolongersidesoruptosixholesaroundthecircumferenceofa
roundpan.
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Anumberofotheraspectsmaycontributetotheproblem.Forexample:
Usingpanswhicharetoosmallforthemassofdoughbeingused(i.e.,
over-scaling,orsimplyhavingthewrongsizeofpan).
Havingtoomuchbottomheatintheoven,suchasmightbethecasein
thedeckoven.
Packingthepanstoocloselytogetherwhichslowsdowntherateofheat
FIGURE4.1
Exampleofpan-lockinbread.
BakingProblemsSolved
4.1.2Weareexperiencingaproblemwiththesidesof
Chapter|4
4.1.3Weareproducinghearth-style(oven-bottom)breads,
raggedcracksappearingalongthesidesoftheloaves.Whatare
thelikelycausesofthisproblem?
Theproblemthatyoudescribesuggeststhatyourdoughsareunder-proved
beforetheyentertheoven.Themainfunctionofproofistoexpandthe
doughbubblestructureusingcarbondioxidegasgeneratedfromyeastfer-
mentation.Itiscommontotrytoachievearound85

90%ofyourrequired
finalproductvolumeintheproverleavingtheremaining10%orsotocome
fromovenspringduringbaking.
Thecrustformsquicklyonoven-bottombreadsbecausetheyarenot
shieldedfromtheheatoftheovenbythesidesofanypans.Quickly,the
doughsurfacesbecomedehydratedandinflexible,butaswithallbreads,
therewillbecontinuedexpansionofthecentreofthedough.Ifthedoughis
under-provedthenthepotentialforcrumbexpansionisconsiderableandthe
forceswhicharegeneratedbegintocrackthealreadyrigidcrustalongany
linesofweakness(see
Fig.4.2
).
Duringproofthechangesindoughrheologymakeitmoreextensible,
lesselasticandlessresistanttodef
ormation.Suchchangesdependmore
ontimethanontemperature.Bymakingthedoughmoreextensible,itis
enceduringtheearlystagesofbakingandsoexpansionismoreeven.An
evenexpansionofthedoughismostoftenseenasuniformovenspring.
FIGURE4.2
Exampleofraggedcrustbreakwithbread.
156
BakingProblemsSolved
Wesuggestthatyoulookcloselyatfinalprooftimeandtheyeastlevel
thatyouareusing.Timeslessthan40minutes,especiallywithhigheryeast
levels,arelikelytoleadtoproblemswithunder-proveddoughs.
Wealsosuggestthatyoulookatsomefactors,suchas:
Thelevelofrecipewater.Commonlyhearthbreadaremadewithslightly
Chapter|4
4.1.4Wehavenoticedthedevelopmentofafruityodour
inourbreadsaftertheyhavebeenstored.Theproblemis
particularlynoticeablewithourwholemealproducts.
Whatisthecauseofthisproblemandarethereanyremedies
wecanapplytopreventitsoccurrence?
Theodourthatyouaredescribingcomesfromaproblemthatbakersreferto
,whichoccursnaturallyinthesoil.Ropebacteriaarecom-
4.1.5Whenviewingthecrumbappearanceofourslicedbread,
wenoticetheappearanceofdarkstreaksandpatcheswhich
haveacoarsercellstructureandfirmertexturethantherest
ofthecrumb.Isthisaproblemwithunevenmixing?
Asthemixingprocessissolelyresponsiblefortheincorporationofthegas
bubbleswhicheventuallybecomethebreadcrumbcellstructurewithno-
timedoughs,itisperfectlyreasonabletoassumethatmixingcanberespon-
sibleforvariationsincrumbcellstructureyouobserve.However,unlessyou
haveagrosslyinefficientmixeroryourdoughsaregrosslyundermixed,
whetherbecauseoftoolittleenergyortooshortatime,wedonotfeelthat
thisisthemaincauseofyourproblem.
Ingeneral,thelargerthesizeofthecellinthecrumb,thedeeperitisand
thedarkerwillbetheshadowthatitcastswhenviewedinobliquelighting
(see
Fig.4.3
).Whendoughsleavethemixer,thegasbubbleswhichbecome
cellstructurearethesmallestsizethattheycanbe.Duringthejourneytothe
oven,carbondioxidegasfromyeastfermentationinflatesthebubblesand
makesthemlarger.Thesizetowhichthegasbubblescangrowislimitedby
Intheeventthattheglutenfilmrupturessmallgasbubblesmaycoalesce
(jointogether)toformlargerones.Thedisplacedglutenfilmmaywellcon-
tributetoimprovingthestrengthoftheremaininglargerbubble.Thickercell
wallsalsocontributetodarkercrumbcolour.
Burstingandcoalescencegasbubblesinthedoughmayoccurifthesur-
roundingmaterialisunabletomaintainbubblestabilityduringprocessing,
especiallyinthoseoperationswhichplacethedoughunderstressesand
FIGURE4.3
Darkpatchesinbreadcrumb.
BreadandOtherFermentedProducts
Chapter|4
159
strains,e.g.,dividingandmoulding.Wewouldsuggestthatyourproblem
arisesbecauseyourdoughlacksthenecessarybubblestability,andtheglu-
lackofbubblestabilitymaycomefromanumberofsources,including:

Usingaflourwhichistooweakforthebreadmakingprocessbeing
employed.

Under-developingthedough,e.g.,toolittleenergyormixingtimetoo
short.

Notusingasuitableimproverwithano-timedough,e.g.,onewhich
lackshardfatoranemulsifier.

Toolittlewaterinthedough,tightdoughsaremoresusceptibleto
moulderdamagethansoftones(
CauvainandYoung,2008
).

Usingcolddoughswhichyieldstiffandunder-developeddoughs.

Insufficientfirstproofwhichgivesadoughwhichisnotsufficiently
relaxedforfinalmoulding.

stage.Thedarkpatchesmayformcharacteristicspatternsinthefinalloaf
whichcanindicatetheirpointoforigininmoulding.
Otherpossiblecausesforvariationsincrumbcellstructureofthetype
thatyoudescribemaycomefromtheinclusionofold,fermenteddoughdur-
ingthelaterstagesofmixingoraccidentallyduringmouldingandprocessing,
Reference
Cauvain,S.P.,Young,L.S.,2008.BakeryFoodManufactureandQuality:waterControland
Effects,seconded.BlackwellScienceLtd.,Oxford,UK.
Furtherreading
).
160
BakingProblemsSolved
4.1.6Periodically,weobservetheformationoflargeholes
inthecrumbofourpanbreadsandsuspectthattheadjustment
isfaulty;canyouconfirmoursuspicions?
(height)playapartintheformationofthelargeholesthatyouseeinyour
doughandthemoulderperformance,andyoumustbearinmindthatany
moulderisinanimateandcanthereforeonlyreacttothematerialthatit
receives.
Inthepreviousquestion,weconsideredhowthestabilityofgasbubbles
wasaffectedbydoughdevelopmentandthestressesandstrainsintroduced
bymoulding.Evenindoughswithoptimiseddevelopmentdamagetothegas
bubble,structuremayoccurduringmoulding.Largegasbubblesformed
fromthecoalescenceofsmalleroneshavealowerinternalpressurethanthe
smalleronesaroundthem.Thislowerinternalpressuremeansthatthecarbon
dioxidegasgeneratedfromyeastfermentationismorelikelytodiffuseinto
thelargegasbubblesratherthanthesmallerones.Inconsequence,thelarge
gasbubblesmaycontinuetogrowtosuchanextentthattheymayform
holesinthefinalcrumb.
Akeytoavoidingthistypeofproblemistoensurethatthedoughrheol-
ogyisoptimisedbythetimeofmoulding(
Cauvain,2015
).Tominimise
stressesandstrainsduringprocessing,youneedadoughwhichlacksresis-
tancetomouldingandisnotelastic.Suchrelaxeddoughscomefrom
ensuringfulldevelopmentwithoptimisedwaterlevels.Colddoughsshould
beavoided,andsufficientfirstproofshouldbegiventolowerdoughresis-
tancetodeformationforthesecond-mouldingstage.Youneedadough
whichisextensible,andthiscomesfromoptimisingglutenformation.
Acommonresponsetotheproblemthatyoudescribeistotightenthe
mouldbyincreasingthepressureexertedduringmoulding.Inmanycases,
increasingmouldingpressureleadstogreaterdamagetothestructureandis
tingshouldjustbeenoughtodelivertheshapeofdoughpieceyourequire
andnothingmore.Insometypesofmoulders,themouldingboardlengthis
tooshorttoachievetherequireddoughsizewithoutsubjectingthedoughto
considerablepressureduringthefinalstagesofmoulding.Theaimofmould-
ingshouldbetoshapethedoughpiecebutpreservethegasbubblesintact.
doughtodeliverthecharacteristicopencellstructure.
BreadandOtherFermentedProducts
Chapter|4
161
Otherfactorswhichmayinfluencetheformationofholesinthecrumb
includeanyskinningofthedoughwhichmayoccurbeforemoulding,the
useofhotpansandexcessivebottomheatintheoven.Inthelattercase,the
holeswhichformmaywelloccurtowardsthebottomoftheloafandmay
haveatriangularshape.
Reference
Cauvain,S.P.,2015.TechnologyofBreadmaking,thirded.SpringerPublishingInternational
AG,Switzerland.
Furtherreading
).
162
BakingProblemsSolved
4.1.7Wehavebeenhavingproblemswithholesappearingin
differentplacesinourpanbreads.Canyouexplainwherethey
comefromandhowtoeliminatethem?Isthereanyrelationship
thedividerandtheproblemsthatweareexperiencing?
First,weshouldpointoutthatitisalmostimpossibletomakebreadwithout
havingproblemswithholesfromtimetotime.Thereareanumberofdiffer-
entoriginsfortheholes,andthereareawiderangeoffactorswhichcontrib-
utetotheirformation.Whenwerefertoholesinbreadcrumb,weusually
meanfeatureswhicharesubstantiallylargerthantheholeswhichwecallthe
cellstructure.Inpanbread,thelatterrangesfrom1to2mmforsandwich-
typebreadupto5

6mmforfarmhouse-typeproducts.Largeholesinbread
crumbareaparticularproblem,butequally,alargenumberofsmallerholes
inthecrumbcanbeacauseforconcern.Tohelpusunderstandtheorigins
ofholesandconsiderhowmighteliminatethem,itisusefultoknowsome-
thingabouttheirkeyfeaturesandtheirlocationwithintheloaf.
Ausefuldiagnosticfeatureofholesistheappearanceofthecrumbwhich
comprisestheirinternalwalls.Thefirstclueoftheiroriginsisgivenby
thehole(see
Fig.4.4
).Insomecases,thestrandsmaybebrokenandleave
theholewiththeappearanceofalimestonecavernwithstalactitesandsta-
lagmites.Inthecaseofthesmooth-surfacedhole(see
Fig.4.5
),itisanindi-
cationthatthesideshadnevertouchedwhilearough-surfacetoahole
suggeststhatsomeforcerippedapartthecrumbintheregionofthehole.
Theotherkeyfeaturefordiagnosticpurposesisthepositionofthehole
withintheloaf,bearinginmindthetypeofbreadwhichisbeingmade.
reachthedoughmouldingandprocessingstages.Thesurvivaloftrappedair
areemployed.Ifafirstmouldingstepisemployed,thereissomepotential
FIGURE4.4
Strandedholes.
BreadandOtherFermentedProducts
Chapter|4
163
becausetheywillbeburstbytheactionoftherolls.However,therheologi-
doughpiece,albeitinamodifiedform.
andstillremainsapopularthemeintreatisesonbreaddoughprocessing.
Suchactionscancertainlybeaccomplishedwithsomebreadmakingpro-
cessesbutlesssowithothers.Forexample,asmuchas70%ofthevolume
ofabulkdoughafterfermentationandbeforeitreaches,dividing(
Cauvain,
2015
natureoftheglutenstructureofferslimitedresistancetodegassingactions.
Incontrast,thegaslevelsindoughpreparedbyano-timedoughmixingpro-
cesswilltypicallycompriselessthan20%ofthedoughvolumeandhavea
rheologymoreresistanttodeformation.Insuchdoughs,eliminatingtrapped
ing,andsuchforceshavesignificantpotentialfordamagingthedoughstruc-
tureleadingtotheformationofareasofcoarsecellstructureinthecrumb
cross-section(see
Section4.1.5
).Acommonapproachwhenholesare
observedinthebreadcrumbistoincreasethepressureputonthedoughas
itpassesunderthemouldingboardofthefinalmoulderbutthisoftenonly
increasestheriskofmoulderdamage(see
Section4.1.6
).
FIGURE4.5
Smooth-sidedhole.
164
BakingProblemsSolved
Thegascellstrappedinadoughpiecehaveawiderangeofsizesfroma
fewmicronsto1

2mm,ormoredependingonthedoughtype.Thelarger
gascellshavelowerinternalpressuresrelativetothesmallercells.Thisdif-
ferenceisanimportantfactorinthegrowthofthegascellswhencarbon
dioxideisproducedbybakersyeast.Ascarbondioxidecannotformagas
bubbleindough(
BakerandMize,1941
),itwillmigratepreferentiallytothe
areasoflowerpressure,thatis,thelargergascells.Theprocessisknownas
disproportionation,anditsconsequencesarethatlargergascellswillgrow
proportionallylargerthansmallgascellinthedough.Thisprocesshasasig-
nificantimpactinthecontextoftheformationofholesinbread.
Thepositionoftheholesinthebakedloafprovidesanumberofimportant
cluesastotheirorigins.Manyunwantedholescomefromtheinclusionofgas
Section9.5
)andas
thedoughpassesunderthemouldingboardonthefinalmoulder.Inaloaf
mouldedfromasingledoughpiece,therelationshipisfairlystraightforward
butwithfour-piecebreaditisnotsoclear.
Fig.4.6
).Usually,theholes
intheloafarecentrallyplaced,havesmoothsidesandrunhorizontally
doughpiece,itdoesnotnecessarilyendupinthecentreofthefinalslice
cross-section.Inpanbreadsmuchoftheexpansionofthedoughinthe
proveroccursinthelowerhalfofthepiece(foranillustrationofthiseffect
see
WhitworthandAlava,1999
),andtheoriginalcentremaywellendup
abouttwo-thirdsofthewayuptheloaf.Inthefour-piecingofdough,the
thedoughbutlargelyconfinedtoeachofthetwocentralportionsandrun-
ningatrightanglestothepanlength(see
Fig.4.7
).Afurthercluethatthe
curlinglinesandsohaveacurvedorcrescentshape(see
Fig.4.8
).
FIGURE4.6
Airocclusioninthedoughpancakeatthecurlingstage.
BreadandOtherFermentedProducts
Chapter|4
165
Thecurlingactioninfinalmouldingformsaroughcylinder,theendsof
whichareopen(
Cauvain,2015
)withthepotentialfortrappinggasinthe
finalstagesofprocessingunderthemouldingboard.Atraditionalrolefor
themouldingboardistheeliminationoftrappedgaswhichhasalreadybeen
discussed,thisdependsonthedoughconditionatthetimeofmoulding.
Underthemouldingboard,thedoughisoftenconstrainedbytwoguide
barsrunningthelengthofthemoulder.Thedoughisscrewedagainst
theseguidebarsbytherollingactiontosealtheendsofthepiece.Itisat
natedtheyarecommonlyseenasholestowardstheendsoftheloafinboth
singleandfour-pieceproducts.
FIGURE4.7
Fig.2.15)insingle(upper)andfour-piecebead(lower).
FIGURE4.8
166
BakingProblemsSolved
Thereisnosingleuniquesolutiontoeliminatingholesinbreaddough.
Tominimisetheappearanceofholesinbread,youwillneedtopayparticu-
tingsthatyouareusingduringdoughprocessing.Ingeneral,youarelooking
tocreateadoughwhichhaslimitedresistancetothedeformationprocesses
atworkinthemouldingstages.Thisimpliesoptimisingthelevelofwater
additionduringmixingbutalsoincludesensuringthatdoughdevelopment
hasbeenoptimised;bothunder-andover-developeddoughscontributetothe
References
Baker,J.C.,Mize,M.D.,1941.Theoriginofthegascellinbreaddough.CerealChem.18,
19

34.
Cauvain,S.P.,2015.TechnologyofBreadmaking,thirded.SpringerPublishingInternational
AG,Switzerland.
Whitworth,M.B.,Alava,J.M.,1999.Theimagingandmeasurementofbubblesinbreaddough.
In:Campbell,G.M.,Webb,C.,Pandiella,S.S.,Niranjan,K.(Eds.),BubblesinFood.
AACC,St.Paul,MN,pp.221

232.
Furtherreading
).
BreadandOtherFermentedProducts
Chapter|4
167
4.1.8Wearemakingopen-toppanbreadsandfindthatthetop
crustofsomeofourloavesisbeingliftedoffduringtheslicing
whereasonotheroccasionsthereisnot.Doyouhavean
explanationforthisproblem?Wehavetriedmakingthedough
strongerbyaddingmoreimproverbutwithoutanyreductionin
theproblem;infact,itmayhavebeenslightlyworse
Theweaknessthatyouareexperiencingjustunderneaththetopcrustproba-
blyhasmoretodowiththedoughmouldingprocessratherthanthe
strengthofthedoughmakingsystem.Yourownobservationsthatadding
moreimproverdidnotsolvetheproblemtendtosupportthisconclusion.
Lookingcloselyatthepicturesofbreadslicesthatyousentthrough,you
canseequiteafewsmallholesthroughoutthecrumboftheloaf.Ontheir
clearlyfollowthemouldinglinesformedinthedoughwhenitisbeing
Section4.1.7
).
Fig.4.9
)followsthe
curveoftheloafcrustandappearstobeassociatedwiththetailofthedough
toplacethisseamonthebottomofthepan(see
Section4.1.22
)wherethe
gaspressurecreatedinthedoughagainstthebottomofthepanislikelyto
isnotpossibletoensurewheretheseamendsupwithrespecttothepan.If
becomingaholeisalsoreduced.
However,ifashashappenedintheillustratedexample,theseamendsup
toexpand.Thereissomerestrictiontocrumbexpansiononcethecrusthas
FIGURE4.9
168
BakingProblemsSolved
mouldinglinestoformlargerholes.Thisappearstobethecasewiththe
faceofthedoughcurl.
Iftheunzippingeffectdoesnotformalargehole,thenitleavesbehinda
weaknessjustunderthecrustwhichcreatesyourproblemsatslicing.The
problemwillbemoreevidentatthetopoftheloafduetotheextraexpan-
sionthatthedoughmustaccommodate.Youarelesslikelytoseethisprob-
lemwithliddedbreads,thoughitdoesoccur,andyoumayalsoexperience
someweaknessjustunderanyofthecrusts.
ofthedoughandthefactorswhichcontributetothatdoughpropertybuttoa
physicalweaknessinthemannerinwhichthebreadcrumbisattachedtothe
crust.Inadditiontothecontributionmadebytrappedgaspockets,thedifferen-
tialinmoisturecontentinthefirstfewmmofthebreadsliceplaysarole.We
notethatthecrustcolouronyourloavesisquitedarkbecauseyourcustomers
preferaheavierbake.Thisdoesmakeacontributiontoyourproblembecause
itreducestheflexibilityofthecriticalareawherecrustandcrumbmeet.
Asyouareautomaticallypanningyourdoughpieces,thereisnowayyou
canguaranteethefinallocationofthedoughpieceseaminthepansoyou
ingcurling.Wesuggestthatyouexaminethepotentialforincreasingthe
moulder.Thedegreetowhichyoucandothisdependsontheoperational
conditionsinyourplant.Certainly,youshouldlooktoreducetheriskof
doughpiecesskinningduringprocessing.
Youshouldalsoexamineyourbreadcoolingprocessandseeifthereis
anopportunitytoreduceoverallmoisturelossandcertainlytrytominimise
wanttochecktherelativehumidityinyourbreadcooler.
Furtherreading
).
BreadandOtherFermentedProducts
Chapter|4
169
4.1.9WeareusingtheChorleywoodbreadprocesstodevelop
ourdoughsandapplyapartialvacuumduringmixingtoproduce
weobservethatthecellstructurebecomesmoreopeneven
thoughthevacuumpumpisstillworking.Canyouexplainthe
causeofthisproblem?
Theapplicationofpartialvacuum(typically0.5bar)duringdoughmixing
withtheChorleywoodbreadprocess(CBP)isusedtoproduceafiner(smal-
leraveragecellsize)andmoreuniformcellstructureinthefinalbakedloaf
(
Cauvain,2015
).Itdoesthisbecausethesizeofthegasbubbleschanges
withchangesinmixingchamberpressure;inparticular,thetransitionfrom
partialvacuumtoatmosphericpressureattheendofmixingcausesthegas
bubbleswhicharepresentinthedoughtoshrink.Atthesametime,it
reducesthetotalquantityofgasinthedoughwhichgivesimproveddivider
weightcontrolandyieldsadoughwhichfeelsdriertothetouch.Thelatter
effecthasallowedusersoftheCBPtoincreasetheaddedwatercontentat
doughmixingtodeliveradoughconsistencysimilartothatobtainedwith
bulk-fermenteddoughswithlowerwatercontents(
Cauvain,2015
).
Theprocessofdoughexpansiondependsofthepresenceofnitrogengas
bubblesinthedough,thenitrogencomesfromtheairbubblesoriginallyincor-
poratedduringmixingwiththeoxygenbeinglostbecauseofyeastaction
(
CauvainandYoung,2006
).Thenitrogengasbubblesprovidethesitesinto
whichthecarbondioxidegasgeneratedbyyeastfermentationcandiffuse.This
nucleatingroleiscriticalascarbondioxideitselfcannotformagasbubblein
breaddough(
BakerandMize,1941
).Withoutsufficientnitrogengasbubbles
beingpresentinthedough,youcannotformanormalbreadcellstructure.
Thenumbersofgasbubblenucleiinthedoughareconsiderablyreduced
asthemixerheadspacepressurefallscloserto0barabsolute(1barvacuum).
InpracticemostvacuumpumpsfittedtoCBP-typemixersaredesignedto
runaround0.3

0.5bar(absolute)becauselowerpressurestendtogive
coarserandmoreopencellstructures.Thesampleofbreadyousupplieddid
notsuggestabreakdownofthegasbubblestructureratherthatithadnot
formedcorrectlyinthefirstplace.Wesuggestthatyoudiscusstheoperation
ofyourvacuumpumpwithyourengineersandequipmentsuppliers.Though
rare,itdoesappearthatthesourceofyourproblemisthatthepumpattimes
isoperatingatpressuresmuchlowerthan0.5bar(absolute).
170
BakingProblemsSolved
Inadditiontothecoarse,opencellstructureacharacteristicofthisprob-
lemisthatthereisextensiveblisteringofthecrustwhichalsohasawaxy,
breads(
Cauvain,2015
).
References
Baker,J.C.,Mize,M.D.,1941.Theoriginofthegascellinbreaddough.CerealChem.January.
18,19

34.
Cauvain,S.P.,2015.TechnologyofBreadmaking,thirded.SpringerPublishingInternational
AG,Switzerland.
Cauvain,S.P.,Young,L.S.,2006.TheChorleywoodBreadProcess.WoodheadPublishingLtd.,
Cambridge,UK.
BreadandOtherFermentedProducts
Chapter|4
171
4.1.10Weareseekingtoimprovethequalityofourbread
doughtemperatureex-mixershouldbe.Canyouadviseusas
howtodecidewhatistheoptimumtemperaturetouse?
Thecontrolofthetemperatureofthedoughdeliveredattheendofmixingisa
criticalfactorinensuringconsistentfinalproductqualityduetoitscontribution
togasretentioninthedough,gasproductionbybakersyeastanddoughrheol-
ogyforprocessing.Whateveryourchoiceoffinaldoughtemperature,itisvery
importanttoensurethatyouareconsistentfromdoughtodough.
Choosingtheappropriatedoughtemperaturetoaimforaftermixingis
independentofproducingadoughwithaconsistentfinaltemperature.In
general,higherfinaldoughtemperatureswillencouragetheyeasttowork
faster,andthiswillspeedupfermentation.Oneofthedisadvantagesofthis
willbethatthebulkdoughdensitywillchangemorerapidlywithtime;as
thebulkdoughdensitydecreases,thiscanleadtogreaterproblemswith
dividerweightcontrolwhileprocessingthebatch.Astheyeastwillbemore
active,youmayfindthatyoucanslightlyreducethelevelthatyouareusing
providedyoudonotcompromisefinalprooftimeandovenspring.
Ifyouareusinganimproverthenbyusinghigherdoughtemperatures
youwillgainincreasedactivityfromtheascorbicacid(AA)presentwhich
contributionoftheenzymicactivityinthedough,andyouwillneedtomake
surethisdoesnotadverselyaffectdoughprocessing.Ingeneral,raisingthe
doughtemperaturewillmakethedougheasiertomouldintoshape,butin
somecircumstances,youmayfindthatthedoughbecomesstickierandyou
mayneedtoreduceaddedwaterlevels.
Warmerdoughsnotonlytendtofermentfaster,theyalsotendto
shorterbake.
Thekeyadvantageinreducingthedoughtemperatureisthatyoucan
limitthepotentialimpactofdoughstickiness.However,lowerdoughtem-
peratureshaveanadverseimpactongasretentionandsotherecanbealoss
ofproductvolumeandcrumbsoftness.Ifyouhaveafixedprooftimethen
youwillneedtoaddmoreyeastwithcolderdoughstomaintainproofvol-
umeforthesametime.Thiscanleadtoproblemsofproductuniformityin
theovenarisingfromtheincreasedtemperaturedifferentialbetweenthesur-
faceofthedoughpieceanditscentre.Acommonproblemarisingfrom
usingcooldoughsandhighyeastlevelscanbethedevelopmentofragged
crustbreaks(see
Section4.1.3
).
Theex-mixerdoughtemperaturescommonlyusedinbakingrangefrom
24to32

Cwithbulkfermentationprocessesusingthelowerendofthe
rangeandno-timedoughmakingprocessesthehigherend.
172
BakingProblemsSolved
4.1.11HowcanIcalculatetheamountoficeIneedtoreplace
someoftheaddedwaterwhenmyfinaldoughtemperature
istoowarm?
Usinganiceslush(amixtureofwaterandcrushedice)orcrushediceto
keepcontrolofthedough,temperatureattheendofmixingisapractical
solutiontounacceptablyhighdoughtemperaturesinthesummermonths,in
countrieswithhotclimatesandwithstrongerflourswhichmayrequirelong
mixingtimesorhighmixingenergies.Thecoolingcapacityoficeisatleast
fourtimesthatofcoldwaterasheatenergyisusedupinconvertingtheice
towaterat0

C.Theicemustbeinaformwhichiseasilydispersedandcan
quicklyuseuptheheatinthedough.
Tocalculatethequantityoficeneededtoreplaceaddedwater,aheat
balanceapproachmustbeused.Theheattoberemovedfromtheadded
water(tocoolittotherequiredtemperature),mustbebalancedagainstthe
heatrequiredtoconverttheicetowaterandthenheatthatmeltedicetothe
minethequantityoficewhichmustreplaceaportionoftherecipeadded
watertoobtaintherequiredwatertemperaturetocontrolthefinaldough
temperature.Aheatbalanceisachievedasshownin
Fig.4.10
.Theformu-
FIGURE4.10
Heatbalancecalculation.
BreadandOtherFermentedProducts
Chapter|4
173
W
i
5
weightofice
W
w
5
requiredweightofrecipeaddedwater
T
t
5
temperatureoftapwaterin

C
T
r
5
requiredwatertemperaturein

C
Heat,Q
1
,toberemovedfromaddedwater
5
(W
w

W
i
)
3
(T
t

T
r
)
3
4.186
Specificheatcapacityofwater
5
4.186J/kg/

C
Heat,Q
2
neededtomelticeandheatresultingwatertotherequiredwater
temperature
5
W
i
3
334.6
1
W
i
3
T
r
3
4.186
Latentheatofice
5
334.6
Forheatbalance
Q
1
5
Q
2
W
w
2
W
i

3
T
t

T
r

3
4
:
186
5
W
i
3
334
:
6
1
W
i
3
T
r
3
4
:
186

4
:
1

Forexample,40kgofwaterisrequiredforadoughmix.Temperatureof
tapwateris20

C.Requiredtemperatureofwaterforthedoughis10

C.
Calculatehowmuchoftheaddedwaterwouldneedtobeice.
Tocool(40kg
2
wtofice)ofwaterfrom20to10requiresQ
1
heatto
beremoved.
Q
1
5
40
2
W
i

3
20
2
10

3
4
:
186
5
40
2
W
i

3
41
:
86
ThisistheheatavailabletomeltW
i
kgice,andtoheatthaticewater
to10

C
Q
2
5
W
i
3
334
:
6
1
W
i
3

10
2
0

3
4
:
186
5
W
i

334
:
6
1
41
:
86

Usingheatbalance(
Eq.4.1
),
40
2
W
i

3
41
:
86
5
W
i
334
:
6
1
41
:
86

41
:
86
3
40

41
:
86W
i
5
376
:
46W
i
418
:
32W
i
5
1674
:
4
W
i
5
4
Ofthe40kgofwaterrequiredfortherecipe,4kgshouldbeaddedasice
and36kgaddedastapwaterat20

C.
Itisworthrememberingthatthewaterwhichislocked-upasiceatthe
startofthemixingisnotavailabletodissolveingredientsorstartthehydration
processesofthedamagedstarchandproteinsintheflour.Thelikelyimpact
ondoughdevelopmentwillbesmallbutmaybemoresignificantifavery
174
BakingProblemsSolved
largemassoficeisused.Inpracticalterms,itisbettertousecrushediceas
thisaidstherapiddispersionofthesmalliceparticlesthroughthedough.In
theory,cubeicemaybeusedbutthisshouldbeavoidedasmuchaspossible.
Ifyouaregoingtoroutinelyaddicetoyourdoughsmakesurethatyou
havealargeenoughicemakingcapacity.Youwillnotonlyneedtocalculate
themassoficethatyouarelikelytoneedforyourmixingsbutalsoneedto
takeintoaccounttheabilityofyouricemakingmachinetodelivericeatthe
requiredrate.Youmayneedtohavesomeformofbuffercontainertohold
theicereadyforuseinthebakery.
BreadandOtherFermentedProducts
Chapter|4
4.1.12Weareusingspiralmixersforourbreaddoughs.
Whatisthebestmixingtimetouse?
Thereisnosimpleanswertoyourquestionbecauseitdependsinpartonthe
typeofspiralmixeryouareusing,yourproductrangeandtheproductqual-
ityyouareseeking.Mostspiralmixershavetwooperatingspeeds;aslow
onemainlyusedtodispersetheingredientsandafasteroneusedtodevelop
thedough.
SpiralmixerstypicallyoperateatlowerspeedsthanCBP-compatible
mixersandthusinagivenmixingtimecannotimpartasmuchenergyto
thedough.Theactualtransferofenergytothedoughwithspiralmixers
dependstoalargeextentontheconfigurationofthemixingbladeand
thosedesignswhichhavemorethanonemixingbladewilltransfera
greaterquantityofenergytothedoughinagiventime.Thepresenceof
afixedcentralbarwillalsohaveasignificantimpactontherateof
energytransfer.
Thus,foragivenmixingtime,wewillexpecttoseedifferencesinthose
Whenyouhavecompletedyourtrialsyouwillprobablyseethatbreadvol-
umeincreasesasmixingtimeincreases(see
Fig.4.11
),reachesamaximum
andthenbeginstofallslightly.Thiswillindicatetheoptimummixingtime
foryourparticularspiralmixer.Thesametimecanbeusedforarangeofdif-
ferentbreadtypes,assumingthatmaximumbreadvolumeandcrumbsoftness
areyouraim.
FIGURE4.11
Exampleoftheeffectofmixingtimewithaspiralmixer(L-R,3,5,7,9min
secondspeed).
BreadandOtherFermentedProducts
Chapter|4
177
4.1.13Whyisitnecessarytocontrolthetemperature
ofbreaddoughs?
Thecontroloffinaldoughtemperaturetoaconstantvalueisessentialto
ensuringconsistencyofproductqualitywhateverthebreadmakingprocess
thatisbeingusedbecausealmostallofthechemicalandbiochemicalpro-
cessesinvolvedinbreadmakingaretemperaturesensitive.Inaddition,many
ofthephysicalpropertiesofdoughwhichinfluenceitsprocessingarealso
directlyaffectedbychangesintemperature.
Acomplexseriesofenzymicactionstakeplaceinfermentingdough,and
allofthesearetemperaturesensitive.Aswithyeast,enzymicactivity
increasesasthetemperaturerisesthoughthetemperatureatwhichmaximum
activityvariesaccordingtotheparticularenzyme.Inbreadmakingprocesses
whichemploysignificantperiodsofbulkfermentationaspartofthedevel-
opmentstage,thenvariationsindoughtemperaturewillhaveaprofound
effectonfinalbreadquality.
Evenchemicalreactionsindough,suchasAA-assistedoxidationare
affectedbytemperature.Lowertemperaturesgivelessoxidationandhence
4.1.14Wehavebeenexperiencingsomevariation
incrustcolouronourbreadproducts.Whatcauses
breadcrustcolourandwhyshoulditvary?
ThecrustcolouronbreadisprincipallyformedbyMaillard-typereactions
involvingreducingsugarsandaminocompounds(freeaminoacidsandter-
minalamino-groupsinsolubleproteins).Forcolourformation,youneed
bothfactorstobepresentinappropriateamounts.Thesereactionstypically
occurfromaround115

C.
Asmallamountofthemainreducingsugar,maltose,maybepresentin
theflourbutinfermentation,provingandtheearlystagesofbaking,the
alpha-
and
catalysedhydrolysisofthestarchintheflourincreases
theamountofmaltosepresent.Amylasesareslowtoattackintactstarch,so
themainsourceofstarchforhydrolysisisthedamagedstarch.Thus,thebal-
anceofenzymicactivityandflourstarchdamagebecomesimportantforcor-
rectcrustformation.
Othersugarswhichmaycontributetocolourformationareglucoseand
fructose,sucroseorlactoseifnon-fatmilksolidsinpresentintherecipe.
Caramelisationmayalsooccur,evenintheabsenceofMaillard-typereac-
tionsbutitoccursatmuchhighertemperatures,usuallyabove155

C.
Thevariationsincolourthatyouareexperiencingmaythereforecome
fromanumberofsources.Assumingthatthebakingconditionsarenotto
blamethenthemostlikelycausesarevariationsindamagedstarchlevelsin
theflourorenzymicactivity,whetherintheflourorfromtheimprover.You
maywanttohavethesechecked.
Rememberthatenzymicactivityistem
peraturesensitivesothatvaria-
tionsindoughtemperaturemaycontri
butetovariationsincrustcolour.
Processingdelaysmaycausedarkerth
anusualcrustcoloursduetothelon-
blemsofdarkcrustcoloursduetoenzymeactivityinthedough.Ifyouare
usingafermentationprocesstodevelopyourdough,youshouldcheckthat
thebulktimeandfermentationconditionsarebeingcarefullycontrolled.
Therearegenerallyadequateamountsofnaturallyoccurringaminocom-
ofnon-fatmilksolidsoranammoniumsaltcanhelp.Reducingadarkcrust
ishardertoachievebecauseitrequirestheremovalofmaterialwhichmay
bealreadyintheflourorimprover.
Furtherreading
InstabilityofFoodandBeverages.WoodheadPublishingLtd,Cambridge,UK.
BreadandOtherFermentedProducts
Chapter|4
179
4.1.15Whyisthesurfaceofsomebreaddoughscut
beforebaking?
Manytypesofbreads,especiallycrustyforms,haveadistinctivepatternof
cutsshowingonthebakedsurface.Thesecutsareusuallymadewhenthe
doughleavestheproverandbeforeitenterstheoven.
Themostobviousreasonforthecutsistoprovideadistinctivesurface
patternwhichdistinguishesoneloaffromanother.Eachcharacteristicpattern
willhaveoriginatedmanyyearsagoandhasnowbecomesoenshrinedin
theproductcharacterthattheyhavebecomepartoftheauthenticityofapar-
ticularproductandpartofconsumerperceptionofproductquality.Ifithas
beencutlikeabloomerandbakedlikeabloomer,thenatfirstglanceina
Cuttingshouldalwaysbecarriedoutwithaclean,sharpknifeandshould
followthetraditionalpatternclosely.Eachbreadtypewillhaveitsowndis-
Chapter|4
4.1.16Whatarethebestconditionstouseforproving
breaddough?
Themainpurposeoftheproofstageinbakingistoexpandthedoughpiece
andmodifyitsrheologytoobtainfurtherexpansionandstructuredevelop-
mentintheoven.Toachievethis,weneedtogeneratecarbondioxidegas
fromyeastfermentation.Soourfirstconsiderationistoprovidethebestpos-
sibleconditionsforyeastactivity.Yeastwillproducecarbondioxidegas
overarangeoftemperaturesrunningfromaround0
C.Asthetemperature
rises,gasproductionincreasesreachingamaximumataround43
C.Bythe
timethatthetemperaturehasreached55
C,allyeastactivityhasceasedand
thecellsaredead.
Usually,weseektoachievearound90%ofourrequiredproductvolume
intheproveddoughleavingthelast10%orsotocomefromovenspring.
Thetimethatittakesforthispointtobereachedintheproverdepends
mainlyoftheprooftemperatureandthelevelofyeastthatispresentinthe
dough,andtosomeextent,thedoughtemperaturewhenitenterstheprover.
Thegreaterthequantityofyeasttheshorterwillbetheprooftimetoagiven
volume.Thus,ifoursolecriteriafordecidingonproofconditionsistoleave
thedoughintheproverforasshortatimeaspossible,thenwewouldchoose
ahighyeastlevelandatemperaturearound40
C,andtoalargeextent
thisisthenorminmostbakeries.
Theotherissuewehavetoconsideristherelativelypoorconductivityof
heatbydough.Thedoughcommonlyenterstheproveratalowertempera-
turethantheairintheprover.Asproofproceeds,theouterlayersquickly
warmwhilethedoughcentreremainscooler.Iftheyeastlevelisveryhigh,
Ifcoolerproofconditionsarechosen,thenyeastlevelsandprovingtimes
willneedtobeadjusted,aswilltheproverrelativehumidity.Coolerproof
tureswhichdeliversamoreuniformproofandovenspring.
Furtherreading
Cauvain,S.P.,2015.TechnologyofBreadmaking,thirded.SpringerPublishingInternational
AG,Switzerland.
Cauvain,S.P.,Young,L.S.,2008.BakeryFoodManufactureandQuality:WaterControland
Effects,seconded.BlackwellScienceLtd.,Oxford,UK.
BreadandOtherFermentedProducts
Chapter|4
183
4.1.17Canwefreezeourunproveddoughpiecesandstore
themforlateruse?
Thefreezingandstoringofunprovedbreadandotherfermenteddoughsis
perfectlypossiblebutdoesrequiresomeattentiontoallaspectsofdough
production,processingandsubsequentuseondefrosting.Thefollowing
guidelineshighlightsomeofthemostimportantareasforattention:

Useano-timedoughmakingprocessasperiodsoffermentationbefore
freezinghaveanadverseeffectonbreadquality.

Useingredientsandadoughformulationwhichgivesgoodproductsby
scratchproduction.Freezingandthawingcannotimproveproduct
quality.

Raiseyourrecipeyeastleveltocompensateforthelossofgasproduction
fromyeastcellswhicharekilledduringthefreezingandstorage.Oruse
ayeaststrainwhichhasagreatertolerancetofreezing.

Freezethedoughasquicklyaspossibleaftermouldingtominimisegas
production.

Youmayneedtoadjustproductdimensionsbeforefreezingasdoughs
themoutforthawing.

Useablastfreezerbutavoidairtemperaturelessthan
2
30

Cdueto
adverseeffectsonproductquality.

Ensurethatproductsarefullyfrozen,aimforacoretemperatureofat
least
2
10

Cbeforepassingtostoragetominimisequalitylosses.

Expectprogressivelossoffinalproductvolumeasfrozenstoragetime
increasessocompensatewithincreasedprooftimes.

Thawtheproductsusinglowtemperaturesandlongtimestominimise
itreachestheendofproof.

Selectcarefullytheproductsthatyouwishtomakewithfrozendough.
cessfulthanthickerproductslikepanbreads
Furtherreading
Cauvain,S.P.,2014.Frozendoughandpar-bakedproducts.In:Zhou,W.(Ed.),BakeryProducts
ScienceandTechnology.WileyBlackwell,Oxford,UK,pp.523

538.
Cauvain,S.P.,2015.TechnologyofBreadmaking,thirded.SpringerPublishingInternational,
Switzerland.
Kulp,K.,Lorenz,K.,Brummer,J.,1995.FrozenandRefrigeratedDoughsandBatters.
AmericanAssociationofCerealChemistsInc.,St.Paul,USA.
Stauffer,C.E.,1993.Frozendoughproduction.In:Kamel,B.S.,Stauffer,C.E.(Eds.),Advances
inBakingTechnology.BlackieAcademic&Professional,London,UK,pp.88

106.
184
BakingProblemsSolved
4.1.18Whathappenswhendoughbakes?
Insimpleterms,whendoughenterstheovenitexpands,losesmoisture,the
differentphysicalandchemicalchangeswhicharesummarisedasfollows:

Gasproductionbytheyeastcontinue
sasthedoughtemperaturerisesinthe
earlystagesofbaking.Whenallofthedoughexceeds43

C,therateofgas
productionfallsandeventuallyceasesby55

C.Althoughthedoughsurface
israpidlyheatedandyeastactivityceases,thepoorheatconductivityof
doughmeansthatthecentrecontinuestoproducecarbondioxidegasfor
sometimeafterthecrusthasformed.Theforcewhichiscreatedbythe
expandingcentremeansthattindoughsp
ringsupwardscreatingovenspring.

Thedoughisalsobeingexpandedbysteampressureandtheexpansion
oftrappedgaseswhicharepresent.

Forthedoughtocontinuetoexpandduringbaking,itmustbeableto
retainthegaswhichisbeingreleased.Thestressesplacedonthedough
duringtheearlystagesofbakingaremuchgreaterthanthoseplacedonit
duringproof,anditisonlyintheoventhatdoughswhichtrulylackthe
tionisseenaslackofovenspringorinmoreextremecasesascollapse.

Thedoughlosesmoisturewithincreasingbakingtime.Themoisture
lossesaregreatestfromthecrust,andthisencouragestheformationofa
crispeating,crustylayer.

TheMaillardreactionsbegintodevelopthecrustcolour(see
Section
4.1.14
).

Thestarchbeginstoswellandgelatinise.Atthistime,moreofit
becomessusceptibletotheactionofany
alpha
-amylaseenzymeswhich
arepresent,andthebreakdowntostickydextrinsandmaltoseisacceler-
atedbythehighertemperatures.

Inthedough,thegasbubbleswhicharepresent,areseparatedfromone
anotherbyathinprotectivefilm.Astheyarenotconnectedwithone
another,theyarecommonlydescribedasafoam.Asbakingproceeds,
thelossofwatermakestheglutenprotectivefilmbecomemorerigid,
andthepressureswithinthegasbubblesrupturetheprotectivefilms.At
thismoment,thefoaminthedoughisconvertedtoasponge,thatis,a
systeminwhichallofthecellsareopenandinterconnected.Atthistime,
thevolumeofthebakingloaffallsslightlyastheinternalandexternal
gaspressuresareequalised.
BreadandOtherFermentedProducts
Chapter|4
185

Moisturecontinuestobelostwhiletheproductremainsintheoven.

Allofthenecessarychangesfromtobakedproductareusuallyachieved
96

C.
Furtherreading
Cauvain,S.P.,2015.TechnologyofBreadmaking,thirded.SpringerPublishingInternational
AG,Switzerland.
Cauvain,S.P.,Young,L.S.,2008.BakeryFoodManufactureandQuality:WaterControland
Effects,seconded.BlackwellScienceLtd.,Oxford,UK.
186
BakingProblemsSolved
wehavebeenhavingcomplaintsaboutourproductsgoingsoft
quickly.Wehavenotchangedourrecipeorprocess.Canyou
helpusunderstandwhathashappened?
Whencrustyproductsleavetheoven,themoisturecontentofthecrustis
muchlowerthanthatofthecentrecrumb.Typicalvaluescanbeaswidely
apartas12and42%,respectively.Fromthemomentofleaving,theoven
thismoisturedifferentialprovidesadrivingforceformoisturemigration
fromthecrumbcentretothecrust.Thismoisturemigrationcontinuesasthe
productbeginstocoolandcarriesonduringsubsequentstorage.Eventually,
thecrustmoisturecontentrisestoalevelatwhichtheproductisnolonger
crisporcrusty.
Therateandextenttowhichthemoisturemigratesfromthecrumbtothe
crustdependsonseveraldifferentfactors,includingthestoragetemperature.
Thelowerthestoragetemperaturethelowertherateofmoisturemigration,
butnotethattherateonnon-moisture-relatedfirming(staling)willincrease
(see
Section4.1.20
).
Theusualprocessforthemovementofmoistureincrustybreadisfrom
crumbtocrustasnaturetriestoachievemoistureequilibriumbetweenthetwo
components.Themoisturecontentofthecrumbfallsandthatofthecrust
rises.Iftheproductisunwrapped,thenthecrustgenerallylosesmoistureto
thesurroundingatmosphere,providedthattheatmosphererelativehumidityis
lowerthanthatoftheloaf.Inpractice,thisismostlythecaseandairdraughts
whichsweepacrosstheproductsurfacecarrythemoistureaway.Thislost
moistureisreplacedbymoremigratingforthecrumbandthewholeproduct
dehydratesandlosesconsumerappeal.
Topreventthisdehydration,wewrapbreadinasuitableprotectivefilm
butifweputcrustybreadintoamoisture-impermeablefilm(e.g.,apolyeth-
ylenebag),thenthemoisturewhichwouldhavebeensweptawayremains
andthebreadquicklycomestoequilibriumwiththeatmosphereinthewrap-
per.Theresultisthatcrustinessisquicklylost.Thealternativeistousea
theholesinthewrappersandhelpkeepcrustcrispnessforalongertime.
Commonlyperforatedfilmsareusedforthepurposes,thesizeanddistribu-
tionoftheperforationsbeingusedtocontroltherateofmoistureloss.
Acommoncauseoflossofcrustcrispness,evenwhenperforatedfilms
areusedcomesfromwrappingbreadtoowarm.Inmanybakeries,bread
freshnessiswronglyequatedtheproductbeinghot,andstaffmaybeencour-
agedtowraptheproductwhilestillwarm.Thispracticehasthreemain
disadvantages:
BreadandOtherFermentedProducts
Chapter|4
187
1.
Moisturewillbelostfromthewarmbreadandcondensewithinthewrap-
per.Themoisturewillbereabsorbedbytheproductcrust,sointhecase
ofcrustybreads,itencouragessofteningofthecrust.
2.
Thelossofcrustcrispnessleavesthebreadsusceptibletocrushingonthe
shelfandintheshoppingbasket.
3.
Condensationencouragesthelocalisedraisingofproductwateractivity
andsoencouragesthegrowthofmoulds.
Infact,yourproblemaroseduetoasubtlechangeinthetypeofperfo-
ratedfilmthatyouwereusing.Feedbackfromthecheck-outstaffinthe
storehadindicatedthatbitsofcrustwerecontaminatingthescannerandso
thescannerproblembutalsoreducedtherateatwhichmoisturewaslost
fromtheproduct,ineffectthesystembehavedmorelikeanimpermeable
bagandthecrustsoftenedmorerapidly.
Thewaytoreducethescannerproblemiscertainlytoreducetheperfora-
areaoffilmsothatthemoisturevapourtranspirationrates(see
Section11.7
)
sizeofthecrustparticleswhichfallthrough,andtheincreaseinthenumbers
willmaintainthelossofmoistureatalevelsimilartothatwhichyouwere
Furtherreading
Cauvain,S.P.,Young,L.S.,2008.BakeryFoodManufactureandQuality:WaterControland
Effects,seconded.BlackwellScienceLtd.,Oxford,UK.
188
BakingProblemsSolved
4.1.20Wehavebeencomparingourbreadwiththatofour
Chapter|4

Maltogenicamylasescanbeaddedtothedoughandthesealsoaffect
firmatalowerrate.
Youshouldalsolookatyourovenbakingconditions.Generally,softer
breadisobtainedisyoucanbakeatahighertemperatureforashortertime,
butofcoursetherearelimitations.Alsocheckyourcoolingprocessand
whetheryoucanshortenthetimebeingtakentocooltheproduct.Theshort-
estpossiblecoolingtimewillbedictatedbythetemperatureatwhichyou
cansliceorwrapyourproduct.Youdonotwanttoencouragecondensation
inthewrapperwhichcanencouragemouldgrowth.
Furtherreading
Cauvain,S.P.,2015.TechnologyofBreadmaking,thirded.SpringerPublishingInternational
AG,Switzerland.
Cauvain,S.P.,Young,L.S.,2008.BakeryFoodManufactureandQuality:WaterControland
Effects,seconded.BlackwellScienceLtd.,Oxford,UK.
190
BakingProblemsSolved
4.1.21Wearehavingproblemskeepingauniformshapewith
ourbloomers.Theytendtoassumeabentorbananashape.
Thishappenseventhoughwetakegreatcaretostraightenthem
thisproblem?
Thiscanbeacommonproblemintheproductionoffree-standingbreads
andcaneasilybeexplained,thoughinsomecasesthesolutioncanbequite
difficulttoachieve.Thebananashape(see
Fig.4.12
)isactuallycreated
towardstheendofthefinalmouldingstage.Asthedoughpiecepassesunder
themouldingboardonthefinalmoulderandisextendedinshapebythe
rollingaction,theendsofthepiecetouchthesideguidebars.Theeffectof
theguidebarsistoslowdowntheprogressofthetwoendsofthedough
piecewhilethecentrecontinuestomoveatahigherspeed.Ifyoulook
closelyatthedoughpiecesastheytravelunderthefinalmouldingboard,
youwillseethishappeningandobservethatthedoughpiecealreadyhasthe
bananashapeyoureferto(
Fig.4.13
).
Duringthepassageofthedoughunderthemouldingboardtheendsand
thecentreofthedoughpiecearesubjectedtodifferentlevelsoftwisting
force.Thismeansthateventhoughyouarestraighteningthedoughpieces
FIGURE4.13
Schematicofbloomerdoughpiecepassingunderthemouldingboard.
FIGURE4.12
Bloomerwithbentshape.
BreadandOtherFermentedProducts
Chapter|4
191
byhand,andeventhoughyouaregivingthem45-minuteproof,thereissuf-
onduringmoulding.Thisproblemismoresevereinbloomersbecausethe
roundcross-sectionafterbaking.
pressureexertedbythemouldingboardraisingitupsothatthedoughpiece
onlyreachesitsfulllengthafterhalfwayundertheboard,ideallyabouttwo-
thirdsofthewaydownthelengthoftheboard.Ifyoucannotdothiswithout
compromisingotheraspectsofshape(e.g.,sealedends),thentheidealsolu-
tionwouldbetouseamoulderwithalongermouldingboard.
Youmayfindsimilarproblemswithanyfree-standingcylindricalshaped
products.Ifyouaretakingalargerdoughpieceandcuttingitintosmaller
individualpieces,youarelikelytofindthatunevenmouldingcontributes
significantlytovariationsindoughpiecedimensionafterbaking.
Youcangainsomebenefitbyprovingthedoughatalowertemperature
foralongertime.Thelongertimeandthereducedtemperaturedifferential
inthedoughpiecebothhelptoyieldamorerelaxeddoughpieceentering
theovenwhichshouldexpandinamoreuniformmanner.Ifyoudoreduce
theprovingtemperature,remembertoslightlyreducethehumidityaswell
otherwisethedoughpieceswillbegintoflowandlosetheirshape.
Ifyoucannotmakeadjustmentstothemoulderorprovingconditions,you
mighttryaslightincreaseinaddedwaterlevel,butthereisadelicatebalance
herebecausemorewaterinthedoughcancausethebloomertoassumeaflat-
terappearance(
CauvainandYoung,2008
).Youmayalsofindthatithelpsto
mixthedoughlongerasyouareusingaspiralmixer,makingsurethatyou
keepthefinaldoughtemperaturethesameasfornormalproduction.
Reference
Cauvain,S.P.,Young,L.S.,2008.BakeryFoodManufactureandQuality:WaterControl&
Effects,seconded.Wiley-Blackwell,Oxford,UK.
192
BakingProblemsSolved
4.1.22Wehavebeentaughttoalwaysplacetheseamofour
mouldedbloomerdoughpiecesdownwardsonthetraybefore
proof,butwedonottakethesameprecautionswithourpan
breads.Canyouexplaintherelevanceofplacingthebloomer
doughpieceseamdown?Shouldwealsodothis
withourpanbreads?
formedafterithasbeencurled.Itisseenasacurvinglineonthefinal
mouldeddoughpiece.Evenwithhandmouldingaseamwillbeformedby
thelastportionofthepiecetobemoulded.Inbakerieswheredoughpieces
arepannedbyhand,thetraditionalpracticeistoplacethemonatrayorina
trayorsling.
Thereareanumberofreasonsforthisprocedure.Thefirstisrelatedto
theappearanceofthebakedproduct.Theportionofthedoughwhichcom-
prisestheseammaynotalwaysbesealedinthefinalstagesofmoulding
andoftenhasthepropensitytouncurlintheproverandtheearlystagesof
baking.Placingtheseamdownwardsusesthepressureofthedoughmass
duringexpansiontoreducetheriskoftheseamunravelling.Iftheseamis
placedonthesidesortopofthedoughpieces,thenanyunravellingwill
causeunsightlysplitsinthecrust.
Inprinciple,theseamshouldbeplacedonthebottomforalldough
pieces.Inautomaticplants,thisisnotgenerallypossiblewhenmakingpan
breadsasthereisnohumaninterventionatthepanningstage.Thistendsnot
tocausesignificantproblemsforthequalityofliddedpanbreadsbecause
theimpactofthelidreducesthepotentialforunravellingofthedoughcurl.
Similarly,thereisareducedriskofunravellingwhenfour-piecingofthe
doughisused(see
Section9.6
),evenwhenopen-topbreadismade.The
greatestriskofqualitylossesfromtherandompositioningoftheseamis
likelytooccurwithopen-topsinglepiecebread.
Onecontributionoftheseamlocationnotoftenappreciatedisthepotential
contributiontotheformationofunwantedholesintheproductcrumb.There
isthepotentialfordamagetothedoughduringsheeting(
CauvainandYoung,
2008
contributetotheformationofunwantedholes(see
Section4.1.7
).Iftheseam
isplaceddownwardsonthetrayorinthepan,thepressuresinthedough
locatedinsomeotherpartofthedoughpiecethepressuresmaybeinsufficient
Reference
Cauvain,S.P.,Young,L.S.,2008.BakeryFoodManufactureandQuality:WaterControl&
Effects,seconded.Wiley-Blackwell,Oxford,UK.
BreadandOtherFermentedProducts
Chapter|4
193
4.1.23Canwemakebreadwithoutusingadditives?
Whatwillbethekeyfeaturesoftheingredientsandprocess
thatweshoulduse?
Therearemanydifferenttypesofbreadandfermentedproductswhichare
madewithoutusingadditives,i.e.,withjustflour,water,yeastandsalt.To
giveasignificantperiodoffermentationtothedough.Thefirststagesof
doughfermentationareusuallycarriedoutwiththedoughstillinitsbulk
form,i.e.,beforeitisdividedintounitpiecesforprocessing,provingand
baking.Thelengthofthebulkfermentationperiodvariesaccordingtothe
strengthoftheflour.Ingeneral,lowproteinfloursaregivenshorterperiods
ofbulkfermentationthanhighproteinflours.Thisisbecauseittakeslonger
forthenaturalenzyme-inducedchangestomodifythedoughglutenquality
withhighproteinflours.
Thelengthofthebulkfermentationtimewillalsoaffectthedevelopment
offlavourinthefinalbread.Itiscommonlyconsideredthatabulkfermenta-
tionperiodofatleast3

4hoursisrequiredfortheretobeasignificant
changeinbreadcrumbflavour.Inmanycases,thefermentationperiodsmay
extendforupto24hours.Inbulk-fermenteddough,asignificantcontribu-
tiontoflavourcomesfromtheactionoflacticacidbacteria(
Wirtz,2003
)
whichdeliverdistinctivelyacidflavournotesinthefinalproduct.
dough,itwillbeveryimportantforyoutocontrolboththetimeandthetem-
peratureoffermentation.Toachievecontrolofthelatter,youwillneedto
worktoaconstantdoughtemperatureandcarryoutthebulkfermentation
undertemperature-controlledconditions;ifyoudonotdothis,thenyoumust
expectvariablebreadquality.
Ifyoudonotwishtofermentthedoughinbulk,thenyoumaychoose
otherdoughingredientsformanyhoursbeforemixingthemwiththerestof
theingredientstomakethefinaldough.Theseprocessesareknownbymany
differentandtraditionalnames;suchassponge(anddough),flyingferments,
sourdoughand
polish
(
Calvel,2003
)andeachcontributesdifferentattributes
tofinalproductquality.
Choosingtherightflourwillbeveryimportanttoyouasyouarerely-
References
Calvel,R.,2003.TheTasteofBread.AspenPublishers,Inc,Gaithersburg,MA.
Wirtz,R.L.,2003.Improvingthetasteofbread.In:Cauvain,S.P.(Ed.),BreadMaking:
ImprovingQuality,firsted.WoodheadPublishingLtd,Cambridge,UK,pp.467

486.
194
BakingProblemsSolved
4.1.24Wemakebreadandrollsusingabulkfermentation
process;canweuseascorbicacid(AA)toimproveourbread
quality?
AAisconsideredinchemicaltermstobeareducingagentoranti-oxidantin
foodsystems.However,inbreadmakingiscommonlyregardedasanoxidis-
ingagent.Thisisbecauseinthepreparationofbreaddough,theAAreacts
withoxygenfromtheairwhichisincorporatedduringdoughmixing.The
reactionindoughconvertstheAAtoasubstanceknownasdehydro-ascorbic
acid(DHA)(inconjunctionwiththeascorbateenzymepresentnaturallyin
wheatflour)andsocanactasanoxidantbypromotingtheformationofdis-
Wieser,2012
).
Thepresenceofoxygeninthedoughisanintegralpartoftheoxidation
processwhenAAisused.Thereisanotherimportantreactioninvolvingoxy-
geninthedough,andthisislinkedtoyeastactivity.Duringmixingandin
theearlystagesofdoughprocessing,theyeastscavengestheoxygenmole-
culeswhicharepresentwiththeresultthattheenvironmentinthedough
changesfrombeingaerobic(i.e.,withoxygenpresent)toanaerobic(i.e.,
withoutoxygen).
Theyeastcancontinueworkingandgeneratingcarbondioxideinthe
anaerobicenvironmentwhichhasbeencreated,buttheAAcannolongerbe
convertedtoDHA.Whenthissituationarises,theAArevertstoitsusual
chemicalfunctionasareducingagentandcanreducethestrengthofthe
propertiesandinturn,alossofbreadvolume.Inbulkfermentationpro-
cesses,theenvironmentinthedoughwillquicklybecomeanaerobic,and
thereisthepotentialfortheAAtoactasareducingagentduringthelong
fermentationperiodwhichfollowsmixing.
ThepotentialforusingAAasanimprover(thatis,toincreasedough
areusing.Ifyouareusingshortperiodsoftime(sayupto2hours),youare
longerperiods,youarelikelytoseetheopposite.Youshouldavoidusing
AAinthespongepartofaspongeanddoughprocess,unlessyouneedthe
reducingeffectforsomereason.
Inpractice,thelevelsofadditionofAAforuseinbulkfermentationshould
belowandlimitedtonomorethan15

20-ppmflourweight(0.15

0.20gto
10kgflour).SomemillerssupplyflourtreatedwithlowlevelsofAA.Youmay
wanttocheckifthisisthecasebecauseaddingmoreAAinthebakerycould
wellcreateproblemsforyourbreadqualityasdescribedabove.
Reference
Wieser,H.,2012.Theuseofredoxagents.In:Cauvain,S.P.(Ed.),BreadMaking;Improving
Quality,seconded.WoodheadPublishingLtd,Cambridge,UK,pp.447

469.
BreadandOtherFermentedProducts
Chapter|4
195
throughwhichitissold.Theyarenotsatisfiedwiththequality.
Wehavesomepicturesoftheproductsconcerned.Thisseemsto
beaone-offandweareatalosstounderstandwhathasledto
theproblem.Canyouhelpusunderstandwheretheproblem
camefrom?
Identifyingthecauseofone-offproblemscanbeverydifficult.Thebest
placetostartistolookatanyproductionrecordsthatyoumayhaveforthe
periodinquestion.Inparticular,youshouldlookatanyprocessinformation
whichmightindicatechangesiningredientbatch,recipeordeviationsfrom
thenormalprocesstimes.Iftherearenosuitablerecordsavailable,thenyou
willneedtostarttheinvestigativeprocessbyrecordingwhatyouseeand
thenworktowardsthelikelycauseoftheproblem.
Ourfirstobservationisthatthereisaclearproblemwiththeshapeofthe
productandinparticularthetopwhichisnotuniforminappearance
(
Fig.4.14
).Therearesomedipsinthesurfacewhicharealsopalerincolour
thanthesurroundingareas.Thepalecolourtellsusthatthesepartsofthe
doughwerenotincontactwiththelidonthepanforthewholeofthebaking
period;otherwise,theywouldhavethesamecolour.Whatisdoesnottellus
Theouteredgesoftheloafshowthatthedoughhadclearlyfilledthe
panatsomestage.Ifexpansionofthedoughwaslateintheoventhenwe
wouldexpectthattheedgesoftheloafwouldbethepaleareas.So,wecan
reasonablyassumethatthepaleareasareassociatedwithacollapsingback
ofthedough.
Theinterioroftheloafshowconsiderablevariationincellstructurewith
considerablecompressionatthebaseandthesidesoftheloaf(
Fig.4.15
).In
contrast,theareainthecentretowardsthetopismoreopen.Thiscouldbe
FIGURE4.14
Loafexternalappearance.
196
BakingProblemsSolved
becausethelidwasnotheavyenoughtocausecompressionunderthetop
crust.However,wehavealreadyconcludedthatinplacesthedoughwasnot
incontactwiththelidlongenoughtobecomeascolouredastherestofthe
crust.Thisinternaleffectisalsoconsistentwithacollapseofthedough
earlyoninthebakingprocessandanalmostcompleterecoveryoftheshape
laterduetothesignificantgasproductionpotentialinthecentreofthe
doughpiece.
FIGURE4.15
Loafinternalappearance.
BreadandOtherFermentedProducts
Chapter|4
onesideofthepanbutthatthebreakisnotformedconsistently
ononeside.Canyouexplainwhythisis?
Theprocessthatyouareaskingaboutisoftencalledovenspringoroven
ofcarbondioxidegasandsteaminthefirstfewminutesintheoven.The
breakformswhenthepressurecreatedbytheexpansionofthecentreofthe
doughpieceissufficienttocauseabreakinthecrustwhichhasformedsoon
afterbakingstarts.Atthistime,thecrustisstillrelativelysoftanddoesnot
havesufficientstrengthtoholdbacktheexpansionforces.Duetoitsrelation
characteristicinfermentedbreadproducts.Theaimistohavecontrolledand
uniformexpansion.Inthecaseofpanbreads,theidealistohaveasmallbut
uniformbreakalongbothsidesoftheloaf.
Thenatureandpreciselocationoftheovenbreakonaloafdependson
manyfactors.Thepresenceorabsenceofmoistureintheovenatmosphere
hasaprofoundeffectontheovenbreak.Alowrelativehumiditytendsto
leadtotheformationofraggedandunevenbreaksthoughthisisusuallya
greaterproblemwithoven-bottomorhearthbreads(see
Section4.1.3
)dueto
thelackofshieldingfromapan.Raisingthelevelofhumidityintheearly
stagesofbakingthroughthedeliberateintroductionofsteamisacommon
practicalwaytocontrolovenspringwithopen-toppanbreads.Steammay
beintroducedwhenbakingliddedpanbreadsthoughitsimpactmaybevery
limitedbythepresenceofthelid.
Acommonfactorwhichcaninfluencetheformationandlocationofthe
ovenbreakisthedeliveryofheattothedoughpiece.Forexample,ifthe
loavesareplacedclosetothesidewallsoftheoven,theywillbeexposedto
greaterradiantheatthanotherloavesmorecentrallyplaced.Thiscausesthe
theovenbreakisonthesidenearesttheovenwall,whereasinothercases,it
willoccurontheoppositesideoftheloaf.Muchdependsonthetotal
amountofheatandtherateatwhichitreachestheproduct.Thiswillvary
thedimensionsofthedoughpieces,thestrappingconfigurationofthepans
andtheirspatiallayoutintheovenchamber.
isabletogentlyexpandintheoven.Optimisingthefinalproofofthedough
sothatithastheappropriaterheologicalcharacteristicsisanimportantfactor
inachievinguniformityofexpansion;asaruleofthumbbakersaimforthe
doughpiecetoachieveabout90%ofthefinalbreadvolumeinproof.
198
BakingProblemsSolved
4.1.27Wearemakingarangeofcrustybreadsusingasmall
breadplant.Weappreciatethevalueofhavinganopencell
However,fromtimetotime,wehavedifficultyinachievingthe
desireddegreeofopennessinthestructure.Canyouhelpus
identifywhythishappens?
Youarequiterightinrecognisingtheimportantlinkbetweentheopennessof
breadcellstructureandtheformationofacrispcrust.Theopennessofthe
finalstructuredependsontwokeyfactors;theabilitytocreatelargegascells
inthedoughandtheirretentionduringdoughprocessing,provingandbaking.
Whendoughleavesthemixer,largenumbersofsmallgasbubblesaretrapped
omyeastfermentat
ioninflatesthese
smallbubbles,andtheygrowlarger.Lateron,duringtheprovingandbaking
stages,thegasbubblesgrowverylarge,be
gintotouchandcoalesce(thatis,join
together)toformevenlargergasbubbles.Itisthesegasbubbleswhicheventu-
allybecomethecellstructureinyourpr
oduct.Tohelpyouappreciatethescales
involvedtheinitialgasbubblesmayrangefrom10to200

minsizewhilethe
cellsinthebakedcrumbaretypically5

15mm;thatis,around100timeslarger.
Akeyprocessinthegasbubbleexpansionisthegenerationofsufficient
carbondioxidegasintheprocessingtimeavailable.Thiswillbeaffectedby
theyeastlevelyouareusing,andthedoughandprocessingtemperaturesand
times.Assumingyouarenotvaryingthetimethenalikelycauseofvariation
maywellcomefromvariationsindoughtemperature.Youmaybecompen-
satingforthesebyadjustingfinalprooftimes,butoften,itistheamountof
mouldingstages)thatmakesthedifferencetotheproductstructure.
Someofthecreationofanopencellstructureoccursinthemixerassome
mixersincorporatelargergasbubblesthanothers.Afterleavingthemixer,it
isbesttodividethedoughintoindividualpiecesandlimitanyfirstmoulding.
Ifyouhavecreatedlargergasbubbles,thenitisimportanttoretainthemdur-
ingprocessing,andthiscanonlybedonewithgentlehandlingofthedough.
Ifyoufindthatyoucannotachievetheopennessofcellstructurethat
yourequire,thenyoumaywanttolengthenthefirstorintermediateproof
time.Ifyoudolengthenthistime,thenyoushouldmakesurethetempera-
tureofthedoughpiecesdoesnotfallandthatthereisnoopportunityfor
skinningtooccur.Youmayalsoneedtoslightlyreduceyourfinalproof
timetomaintainaconstantdoughpiecesizeenteringtheovenbutnoso
muchastoendupwithunder-provedloavesasthismayleadtootherquality
problems,suchasraggedbreaks(see
Section4.1.3
).
productistoensurethatthereareminimalvariationsindoughtemperature
andtoensurethatyourmouldingregimeispreservingthelargergasbubbles.
Thinkofthelargergasbubblesasbeingeggsandthattheobjectiveofdough
processingistocarrythemunbrokeninthedoughtotheprover.
BreadandOtherFermentedProducts
Chapter|4
199
4.1.28Duringthemanufactureofbreadandotherfermented
4.1.29Ourtotaltimeforbreadproductionfromflour
fermentationtimeof4hoursandafinalprooftimeof
90minutes.Wefindthatwithincreasedbreadsalesthatwedo
nothaveenoughprovingcapacity.Ifweweretoshortenthe
finalprooftimewhatotherchangeswouldwehavetomaketo
maintainourcurrentbreadquality?
Finalproofhastwoimportantfunctions;oneistoencouragetheproductionof
carbondioxidegasbytheyeastandtheotherisallowsomemodificationof
therheologicalpropertiesofthedoughsothatitwilllosesomeofitselasticity.
Thislatterchangeisimportantasitallowsforamoregradualexpansionofthe
doughintheovenandthedeliveryofasmoothanduniformovenbread.
Breadwhichisunder-provedisoftencharacterisedbyaraggedorwildcrust
break,sometimesreferredtoasaflyingtoporraggedbreak(
Fig.4.16
).
Inviewoftheabovecomments,therewillbeaminimumfinalproof
timethatyoucanusewithoutcompromisingbreadquality.Youwillneedto
exploretheoptionsforyourselfasthisminimumtimeisaffectedbythe
doughtemperatureandfinalproofconditions.Asaguide,youcouldreduce
yourfinalprooftimetoabout60minutesandwewouldsuggestthat(pro-
videdyouhavetheprocessspaceavailable)thatyoucompensatebyincreas-
ingyoubulkfermentationtimetoabout4.5hours.Thischangeshould
maintainyourexistingbreadqualitywithouttheneedforrecipechanges.
Ifyouarenotabletoextendyourbulkfermentationperiod,thenyou
wouldhavetoslightlyincreasethelevelofyeastthatyouareusingtoensure
thatyoumaintaindoughvolumeattheendofproof.Youmayfindthatwith
extrayeastthatyouneedtocutbackyourbulkfermentationtimeslightly.
FIGURE4.16
Flyingtop.
BreadandOtherFermentedProducts
Chapter|4
201
spongeandafermentandwhenwouldtheybeused?Wehave
alsoseenreferencestobarms,canyoutellusanythingabout
theseaswell?
Bothspongesandfermentsarebasedontheprincipleofinitiatingyeast
fermentationbeforethemainbreaddoughmixingstageofbreadmaking.
whichtheystandbeforebeingusedandthatthefermentwillbeofamuch
softerconsistencywithlessflourbeingusedinthefermentrecipe.
Thebasicrecipeofaspongecomprisesflour,water,saltandyeastand
aftermixingthespongeisallowedtostandforseveralhoursbeforeit(ora
portionofit)istransferredtothemixerwheretherestofthedoughingredi-
Section
4.1.31
).Theratioofwatertoflourinthespongeissimilartoorslightlyless
thanthatusedinastandarddough.Theyeastlevelinthespongeisusually
lowasitwillbefermentingformanyhours,commonly10

20.Duringthe
fermentationperiod,thespongewilldevelopadistinctiveacidflavourprofile
whichwillbecarriedthroughtothefinalproduct.Thespongealsocontri-
butestothedevelopmentofthefinaldough.Afterfinaldoughmixing,the
bulkdoughisusuallydividedimmediatelyforfurtherprocessing.
thisisnowalesscommonprocessthanthespongeanddough.Typically,the
fermentwillcontainflourandwaterinatleastequalparts,alloftheyeast
allowedtostandforashortperiodoftime,typically20

40minutes,before
beingmixedwiththeotheringredients.Afterfinaldoughmixing,itiscom-
montoleavethedoughinbulkforashortperiodbeforedividingitintounit
piecesforfurtherprocessing.Thefermentcanbeparticularlyusefulifyou
areusingdriedyeastthatrequirespre-hydration(see
Section2.6.7
).
Barmsarenotoftenseeninusethesedays,ifatall.Theywerebasedon
theuseofdistillersyeastfromthemaltingsandwereoftenseeninusein
complicatedandreliedonthepreservationofaportionofbarmforusein
subsequentbatches.Theprocessstartedwithmaltandwaterbeingmashed
togetherforseveralhours.Aliquorwaspressedfromthemixture,flourstir-
redinandboilingwateraddedtogelatinisetheflour.Thescaldasitwas
calledgraduallycooledover24handaportionofoldbarmfromaprevi-
ouslypreparedbatchadded.Thismixturewasthenfermentedfor3

4days
beforebaking.Barmswerenormallypreparedtwiceaweek.
202
BakingProblemsSolved
4.1.31Howwouldweprepareanduseasponge
withtheChorleywoodbreadprocess(CBP)?
ThepreparationanduseofaspongewiththeCBPisnotdifficult.Thecommon
useofaspongeiswithno-timedoughprocesses(i.e.,thedoughmovesfrom
completionofmixingtothedividerwithoutdelay).Theonlyspecialfacilities
thatyouwillneedwouldbetheprovisionofspaceforstoringthesponges.
Togetconsistentresults,youshouldstorethespongesundertemperature-
controlledconditionsandcoverthemtopreventdehydrationandtheformation
ofaskinonthesurface.Itwillbeimportanttousethespongesinstrict
rotation.Ideally,youwouldmakeonespongeforeachdoughand,thatis,
thebasisoftherecipegivenbelow.Inpractice,thismaybedifficultdueto
spaceconditions,soyoumayhavetomakealargerspongeanduseportions
forseveralsuccessivedoughs.Ifthatisthecasewesuggestthatthesponge
shouldnotbeusedformorethan20

30minutesofdoughmakingtominimise
therisksofqualityvariations.Inprinciple,theseprecautionsarenodifferentto
usingaspongewithanyotherspongeanddough-typeprocess.
Thereisnoneedtofullydevelopthespongesoyoumayuseanother
mixerforitspreparation.YoucanuseyourCBP-typemixerforthesponge
preparation,butyouneedonlymixforashortperiodoftime;thiswillbe
helpfulincontrollingthespongetemperature(seebelow).
Thelevelofspongethatyoupreparedependsonthehowmuchyouwish
tochangethecrumbflavour;thelargerthequantityofspongeusedthestron-
gertheflavourprofile.Wesuggestthatyoutryaquartersponge;thatis,using
onequarterofthetotalflourweighttopreparethespongeasfollows:
IngredientWeight(kg)
Flour12.50
Water7.00
Yeast0.10
Salt1.25
Mixtocleardoughwithafinaltemperatureof20

Candfermentfor16h.
Doughmaking
Addthespongetotherestoftheingredientsinthemixer,i.e.,3/4ofthe
flourwithappropriatewater,salt,improverandyeast(thelattermaybe
reducedbyabout5

6%ofitsoriginallevel).
Donotincludethequantityofspongeinyourenergycalculation.
Furtherreading
Cauvain,S.P.,Young,L.S.,2006.TheChorleywoodBreadProcess.WoodheadPublishing,
Cambridge,UK.
BreadandOtherFermentedProducts
Chapter|4
203
4.1.32Ourbreadandbunsprovetoasatisfactoryheightin
intheoven.Wehavetriedincreasingitsstrengthandusingmore
improver,butwhateverwedoweseenoovenspring.
Therearetwoprocesseswhichcontributetoovenspring;gasproductionand
thattherewasnoimprovementinovenspringstronglysuggeststhatthe
problemiswiththegasproductioncapabilitiesofthedough.
Initially,gasproductioninthedoughreliesontheabilityoftheyeastto
fermentthesugarswhicharepresentinthewheatflourtoproducecarbon
dioxideandalcohol(see
Section2.6.2
).Ifthereareaddedsugarstheyeast
mayusethese;firstthemono-saccharides(simplesugars)andlaterthedi-
saccharides.Thereisalsosomemaltosesugarbeingproducedastheamylase
enzymesinthedoughbegintobreakdownthedamagedwheatstarch.
regulatedbytheosmoticpressure(see
Section11.12
)acrossthewallsofthe
yeastcell.Inpart,thisosmoticpressureisaffectedbythenatureandconcen-
trationofsolubleingredientsintherecipe.Inadditiontothesugarsalready
mentioned,solubleingredientsinthedoughwhichhaveaneffectonyeast
activityincludesalt(sodiumchloride)andpreservativessuchascalcium
propionate.
ableinthedough.However,thetransitionfromonefoodsourcetoanother
cessesintheyeastslowdownandgasproductionfalls.Aftertheyeasthas
madetheadjustmentgasproductionwillagainincrease.Fromthedescription
ofyourproblem,itappearsthattheyeaststrainthatyouareusingismaking
oneofthesetransitionsasthedoughbeginstoreachtheovenandsoisnot
abletoprovidethelastburstofcarbondioxidegaswhichnormallycontri-
butestoovenspring.
Differentstrainsofbakersyeasthavedifferenttolerancestosugar
(osmotolerance)andcalciumpropionate.Theyproducecarbondioxidegasat
differentratesfromotheryeaststrainsinthedoughandsomaybemore
suitableforyourbreadandbunproduction.Youwillneedtoconsultwith
youryeastsuppliertofindthemostsuitablestrainofyeastforyourparticu-
larrecipeandprocessingconditions;oncethatyouhavethemostappropriate
strainofyeast,wearesurethatovenspringwillberestored.
204
BakingProblemsSolved
4.1.33Weareexperiencingaproblemwithloavesbakedin
rackovenssinceweboughtnewpans.Astheenclosed
portionsoftheloavesthattouchhavenocrustformationwhich
makesthemweakwhentheyaredepannedandhandled.How
canwepreventthisfromhappening?
Inthephotograph,itisclearthatthedoughhasrisenwellduringtheearly
stagesofbakingandloavesinadjacentpansinthestraphavetouched
(
Fig.4.17
).Consequently,thesepartsoftheloafdidnotformasolidcrust
andhadapale,under-bakedpatchontheside.Ontheendsofthestrap
wherethedoughhasoverflowedslightly,anormalcrustwasformed.
Youindicatedthatyouchangedtonewpansrecentlyandnowhavefour
smallpansacrosstherackwidthwhereyouhadthreepreviously.Ifbread
pansarestrappedtoocloselytogether,thenwithawell-developeddough,
thiskissingofadjacentloaveswilloccurastheygrowintheoven.Thisis
finalproofofthedough,albeitintheoven.
oftheovenincirculatingairthroughthegaps.Ovenswhichprovidesignifi-
airconvection.Airflowinfan-assistedrackovensmaynotbeasgoodatcir-
culatinghotairasforcedconvectionovens.
FIGURE4.17
Touchingloaffromnewstrapsofpans.
BreadandOtherFermentedProducts
Chapter|4
205
Ifthescaledweightofthedoughpiecedepositedinthepansistooheavy,
thenthismaybeacontributortotheproblem.Thescalingweightsshould
becheckedforconsistency.Withthecurrentderegulationofbreadweights
inmanypartsoftheworld,itmaybepossibletoslightlyreducethedough
scalingweightprovidedthefinishedbakedweightiswithintheweight
specificationfortheproductatpointofsale.
4.1.34Wewishtocreateaboldershapeandmoreopencell
structurewithourcrustysticksandhaverecentlyincreased
ourdoughdevelopmentbymixinglonger.Now,weexperience
under-provethedoughpieces,wehaveproblemswithragged
breadandpoorshapes.Shouldwereduceourmixingtimeback
toitsoriginallevel?
Thisproblemhassimilaritieswiththatin
Section4.1.33
.Ourfirstresponse
isthatyoushouldnotseektosolveyourproblembyunder-provingthe
doughpieces,indeedyouowninformationsuggeststhatthiswillonlylead
tounacceptableproductquality.Wedonotrecommendthatyougobackto
thedoughbecauseitwillbelesswelldeveloped.Thiswillnothelpyou
achievethevolume,boldnessofshapeandopennessofcellstructurethat
youareseekinginthefinalproduct.
Youhavebeenscalingthedoughpiecestogiveyoua400gbakedweight
intheproduct,buttheindentedtraysthatyouareusingweredesignedfora
lowerdoughpieceweightwhichwoulddeliverabakedstickweightof300g
meansthatthecross-sectionofthestickistoolargefortheindentonthe
tray,thepiecesarenotsupportedattheirsidesandsoflowovertheedgesto
touchoneanother.
Asyoudonotwanttoreduceyourscalingweighttodeliverabakedstick
weightof300gorlessthisleavesyouwithtwopossibilities;oneistoonlybake
threestickspertraybyplacingdough
piecesinalternateindents.Thiswill
reduceyouroverallbakingcapacityandyoumayneedtoreduceyourbatchsize
accordingly.Theothersolutionwouldbetoseekatraydesignwithonlyfour
Fig.4.18
).Ifyouaregoing
tousethissolution,thenwealsosuggest
thatyouseekaslightlydeeperprofile
BreadandOtherFermentedProducts
Chapter|4
207
FIGURE4.18
Alternativecrustysticktrays.
BakingProblemsSolved
4.1.35Wearefindingthatthecrumbofourbreadistoosoft
forslicing.Wealsonoticeatendencyforthesidesoftheloaves
toslightlycollapseinwards.Wedonotthinkthatconditionsin
ourcoolerhavechangedcanyoupleaseadviseusofwhatto
investigate?
Whenbreadleavestheoventhecrustisfirm,butthecrumbisstillrela-
tivelysoft.Intheinitialstagesofcooling,thecrumbbeginstofirmasthe
amylosefractionofthewheatstarchbeginstoretrograde(recrystallise).The
longer-termfirmingeffectassociatedwithbreadstalingisrelatedtotheret-
rogradationoftheamylopectinfractiononthestarch.Itistheinitial
increaseinfirmnessduetotheamyloseretrogradationwhichallowsthe
breadtobeslicedmechanically.Thelengthoftimethatthebreadspendsin
thecoolerisusuallylinkedwithcoreloaftemperatureatwhichthebread
canbesliced.Typicalloafcoretemperaturesforbreadslicingareinthe
order27

30

C.
Ofcourse,theabilitytoslicealoaf
mechanicallyisalsolinkedwith
thecrumbmoisturecontentandthelowerthemoisturecontentofthe
crumbtheeasieritwillbetoslice.However,breadsoftnessisreduced
whenthecrumbmoisturecontentislower,soitiscommonpracticeto
limitasmuchaspossiblemoisturelossesduringcooling.Thesidesof
fromtheloafduringcooling.
Anumberofingredientswhichareusedintherecipealsoplayarolein
saidtoimprovecrumbsoftnessthoughwiththelowfatlevelsusedinmany
breadsthiseffectismostlikelytobeassociatedwiththeaccompanying
improvementinbreadvolume.
Theadditionofanti-stalingagentscanhaveanimpactontheinitial
crumbsoftnessinadditiontothelonger-termanti-stalingeffects.Inthiscon-
text,theadditionofmodifiedbacterial(maltogenic)amylaseshasbecome
popularinmanybreadtypes,andhighlevelsofadditionhavebeenassoci-
atedwithexcessivelysoftcrumbatslicing.
Theslightcollapseinwardsoftheloafsidesalsosuggeststhatthelevel
ofenzymeadditionistoohighinyourrecipe.CheckthattheflourFalling
Numberisnottoolowandtalkwithyoursupplieraboutmakingasmall
reductioninthelevelofenzymeadditioninyourimprover.
Furtherreading
Cauvain,S.P.,2015.TechnologyofBreadmaking,thirded.SpringerPublishingInternational
AG,Switzerland.
BreadandOtherFermentedProducts
Chapter|4
209
4.2OTHERFERMENTEDPRODUCTS
4.2.1Canyousuggestwhatstepscouldbetakentoprevent
ourrounddoughnutsshrinkingorcollapsingwithinafew
minutesofleavingthefryer?
Thecollapseofyourdoughnutsaftertheyleavethefryerisassociatedwith
thetransitionofthedoughfromafoamtoasponge(inthegenericnot
specificcakemakingsense).Infoams,thegasbubblesorcellsareseparated
fromoneanotherbyastabilisingfilmofoneformoranother,e.g.,protein,
fat,emulsifier,whereasinasponge,thecellsareinterconnectedandgases
andliquidscanreadilypassthroughthematrix(see
Fig.4.19
).
Intheoven,mostbakedproductsundergothetransitionfromfoamto
spongeandthegascontainedwithintheindividualcellsdiffusesoutofthe
productintothesurroundingatmosphere.Thetransitionoccursatdifferent
partsofthedoughpieceatdifferenttimes,dependingontheheattransfer
ratefromthesurfacetothecentreofthepiece.Beforeconversion,thepres-
sureinsidetheairbubblesisgreaterthanthatofthesurroundingatmosphere,
andthiscontributestoinflationoftheproduct.Atthemomentofconversion
fromfoamtosponge,thereisanequalisationofthegaspressureinsidethe
foamwiththatinthesurroundingatmosphere,andthisisseenasaslight
shrinkingofthevolumeofthebakedproductjustbeforetheendofbaking.
Theprocessinthedoughnutfryerisessentiallythesameasthatfordoughin
theoven.Infact,theincreasedpressureinsidethegasbubblesinthedough
foamcontributestowhatmakesdoughnutsfloatinthehotoil.
Theadditionofsomeingredientscandelaytheconversionofthefoam
toaspongetoalatertimeduringthebakingprocess.Assugarisalmost
alwayspresentindoughnutformulations,itisimportanttoappreciatethe
rolethatitplaysintheformationofdoughnutstructures.Sugar,intheform
ofsucrose,delaysthegelatinisationofthewheatstarch,andsubsequently,
thetemperatureatwhichthefoamtospongeconversionismade.Insome
formulations,thestarchgelatinisationtemperaturecanberaisedsohighthat
inthecentreoftheproductitmaynotevenoccurbeforefryingiscom-
pleted.Asaconsequence,someofthefoamremainsintactandasthetem-
peraturewithinthecellsfallssodoestheinternalpressure.Atsomepoint,
theexternalpressureontheproductbecomesgreaterthantheinternalpres-
sureinthecellsandtheproductshrinks.Thisisthecollapseandwrinkling
oftheproductthatyousee.
FIGURE4.19
Transitionfromfoamtosponge.
210
BakingProblemsSolved
Itiswellknownthatamechanicalshockdeliveredtomanysuchproducts
canbeusedtoeliminatethistypeofproblem,sosimplybangingthetraysas
youremovethemfromthefryercanreduceoreveneliminatethisproblem.
However,thisisnotmaynotbeeasytoachieveinacommercialbakery,and
sotoavoidtheproblem,youshouldlooktoreducethesugarlevelinthe
carefulnottoloseoverallproductvolume.
Furtherreading
Aguidetodoughnuttechnology.
ChorleywoodBookshelfMonographNo.2.
).
BreadandOtherFermentedProducts
Chapter|4
211
4.2.2Thefermenteddoughnutswearemakingtendtobequite
greasytoeat.Canyouadviseonhowwecanreducethis
problem?
Duringthefryingprocess,theheatexpandstheairbubbleswhicharetrapped
withinthedough,carbondioxidegasisevolvedfromthelastoftheyeast
activityandsteamisgivenoff.Whileallofthisistakingplace,thepressure
withinthedoughpieceisgreaterthanthatofthesurroundingatmosphere,
andthisgreaterinternalpressurepreventstheabsorptionofoil.Oncethe
transitionfromfoaminthedoughtospongeismade(see
Section4.2.1
),the
pressurewithinthedoughbecomesequaltothatoutsidethedough,anditis
Infact,muchoftheoilabsorptionthatoneseeswithdoughnutsoccurs
aftertheproducthasleftthefryer.Inparticular,anypoolsofoilwhich
remainofthedrainingwiresincontactwiththefinalproductprovideeasy
accessoftheoilbelowtheproductsurface.Youshouldtrytofindameans
ofshakingoffasmuchexcessoilaspossiblebeforeleavingthedoughnuts
tostand.Insomecases,tappingorbangingofthetrayscanbeemployedand
thismayalsohelpavoidproblemsofcollapseandwrinkling(see
Section
4.2.6
).
Othermeansofreducingoilabsorptionindoughnutsinclude:

Addingalowlevelofacellulose-basedmaterialtotheformulation(up
0.3%flourweight).

Maximisingtheaddedwatercontentofthedoughasthiswillhelpto
increasethesteampressureduringfrying.

Ensuringthatthefryingtemperatureoftheoildoesnotfalltoolow.
Typically,itshouldbeabout180

C.Toolowanoiltemperaturereduces
theheatinputandlengthensthetimethatthedoughnutspendsinthefat
afterthefoamhasconvertedtoasponge,therebyincreasingthetimefor
Furtherreading
Aguidetodoughnuttechnology.
ChorleywoodBookshelfMonographNo.2.
).
212
BakingProblemsSolved
4.2.3Wehaverecentlybeenexperiencingdifficultieswiththe
productionofourbreadrolls.Thefinishedrollshavepoor
volumewithlargeholesinthecrumb.Canyousuggestmeasures
wemighttaketoeliminatethesefaults?
Yourproblemwithsmallvolumemaycomefromanumberofsources,all
(volumeperunitmass)ofrollsisnormallyexpectedtobegreaterthanthat
dough.Youcanachievethisinanumberofwaysincluding:

Usingastrongerflour.Itiscommonpracticetouseahighergradeof
flourforrollsthanbread.

Raisingtheleveloftheimproverthatyouareusing.Often,breadimprovers
areusedat1%flourweight,andthismaybeincreasedto2%forrolls.

Changetoamorepowerfulimprover,thatis,onewhichwillgive

Ensurethatthedoughisfullydevelopedduringthemixingcycle.This
mayentailraisingworkinputintheCBPormixinglongerwithother
breadmakingsystems(see
Section4.1.12
).

Raisethedoughtemperaturetoaiddoughdevelopment.Ifexcessivegas
productionbeforemouldingbecomesaproblem,simplyreducetheyeast
level.
Theholesthatyouobservearemostlikelytocomefromdamagetothe
gasbubblestructureduringmoulding.Thereareanumberofreasonswhy
thisdamagemightoccurincluding:

Thelevelofwaterinthedoughbeingtoolowsothatmouldingpressures
havetobeincreasedtoachievetherequiredshape.

mouldingstagesistooshort.

Thedoughtemperaturebeingtoolowgivingamoreviscous(stiff)dough
similartohavingtoolowawaterlevel.
BreadandOtherFermentedProducts
Chapter|4
213
4.2.4Wehavebeenreceivingcomplaintsthatoursmall
fermentedproducts,suchasrolls,teacakesandbaps,
arestalingtooquickly.Canyouadviseonhowwecanimprove
theproductsoftness?
Thereareseveraldifferentwaysinwhichyoucanimprovethesoftnessof
yourproducts.Theycanbegroupedundertheheadingsofimproving
volume,raisingmoisturecontent,
usingfunctionalingredientsand
storage.
4.2.4.1Improvingvolume
Ingeneral,larger-volumeproductswillhaveasoftercrumb.Thisisbecause
mouth,isreduced.Youwillneedtoensurethatthedoughhasbeenfully
developedbeforebakingasthisgivesadegreeofresiliencetothecrumb
whichisimportantfortheoverallqualityoftheproduct.Rollswhichshow
noresiliencyaftercompressionwhiledefinitelyappearingsoftlacktheche-
doughdevelopmentoftencomesfromprinciplessuchasextendingdough
mixingtimes(see
Section4.1.12
)orincreasedenergyinput.
4.2.4.2Raisingmoisturecontent
Thehighertherecipewatercontentinthedough,thehigherthemoisture
contentinthefinalproductwillbeforafixedbakingtimeandtherefore
thesofteritwillbe.Youshouldlooktomaximisethewateradditionto
thedough,thiswillalsohelpdoughdevelopment.Tryalsotobakeless
wateroutintheoven,thefinalmois
turecontentismoreaffectedbythe
lengthoftimethattheproductspendsintheovensothereareadvantages
toraisingthebakingtemperatureandreducingthebakingtime.Someof
themoisturefromthecrumbwillinevitablymigratetothedriercrustto
achieveequilibrium.Keepingthecrustthinmeansthatlesswaterisneeded
toachieveequilibrium(
CauvainandYoung,2008
).
4.2.4.3Usingadditives
Thereareanumberoffunctionalingredientswhichmaybeusedtoimprove
sodiumstearoly-2-lactates(SSL)(
Cauvain,2015
).GMSformscomplexes
withthestarchandsohasatrueanti-stalingeffectinfermentedproducts
(
Cauvain,2015
).
214
BakingProblemsSolved
Additionsofenzymeactivematerialsarealsouseful.Forexample,the
so-calledmaltogenicorintermediatethermalstabilityenzymeshaveabene-
ficialanti-stalingeffect,whereasfungal
alpha
-amylasecanbeusedto
increaseproductvolume(
CauvainandChamberlain,1988
).Lipaseenzymes
arealsoknowntohaveanantistalingeffectastheysplittri-glyceridesinthe
doughtoformdi-andmono-glyceridesinsitu
.
4.2.4.4Storage
Itisimportanttowrapyourproductsasquicklyaspossibleaftercoolingina
moistureimpermeablefilmtominimisemoisturelosses.Youshouldalsobe
carefulwhereyoustoretheproductsbecausebreadstalingproceedsfasteras
thetemperaturefalls(
Cauvain,2015
),soavoidstorageareaswherethe
ambienttemperaturefallsbelowabout15

C.
References
Cauvain,S.P.,2015.TechnologyofBreadmaking,thirded.SpringerPublishingInternational
AG,Switzerland.
Cauvain,S.P.,Chamberlain,N.,1988.Thebreadimprovingeffectoffungal
alpha
-amylase.
J.CerealSci.Nov.8,239

248.
Cauvain,S.P.,Young,L.S.,2008.BakeryFoodQuality&Manufacture:WaterControland
Effects,seconded.Wiley-Blackwell,Oxford,UK.
BreadandOtherFermentedProducts
Chapter|4
215
4.2.5Ourfruitbreadsriseveryslowlyintheproverandfailto
riseanyfurtherintheoven.Wemakesomeunfruitedproducts
withthesameformulationandtheyaresatisfactoryinall
respects.Canyouexplainwhy?
Astheproblemisassociatedonlywithfruitedproducts,thenwemustlookto
thefruitforthecause.Youappeartohaveaproblemwithbothgasproduc-
theslowproof
4.2.6Ourfruitedbunsfrequentlycollapsewhentheyleave
theoven.Wehavetriedbakingthemforlongerbutthisdoesnot
curetheproblem.Ourfruitedloavesmadewiththesamedough
donothavetheproblem.Canyouadvise?
Thecauseofthisproblemisessentiallythesameasthatdescribedforthe
doughnuts(see
Section4.2.1
).Namelythat,thetransitionofthedoughfrom
afoamtoasponge(inthegenericnotspecificcakemakingsense)isnot
occurringintheovenandthegaseswithintheindividualbubblesorcellsare
notdiffusingoutoftheproductintothesurroundingatmosphere.During
cooling,theexternalpressurebecomesgreaterthanthepressurewithinthe
intactbubblesandtheproductshrinks,collapsesandthecrustwrinkles.No
amountofextrabakingwillcuretheproblem.Toavoidtheproblem,you
shouldlooktoreducethesugarlevelintheformulationorreducetheability
Itiswellknownthatamechanicalshockdeliveredtomanysuchproducts
canbeusedtoeliminatetheproduct,sosimplybangingthetraysasyou
removethemfromtheovencanreduceoreveneliminatethisproblem.But
careshouldbetakentoavoidpersonalinjuryordamagetoequipmentand
trays.Ifthemechanicalshockistooviolent,thenitispossibletocrackthe
crustsurfaceoftheproductasitlacksthenecessaryflexibilitytowithstand
themechanicalstresses.
Youarelesslikelytoseetheproblemwiththedoughbakedinpans
becausethestandardprocedurewhenyoutaketheproductsoutoftheoven
insmallerbakeriesistogivethepansasharpknocktoreleasetheproduct
fromthepanforcooling.Thisdepanningactiondeliverstherequired
mechanicalshocknecessaryforthedisruptionofthegascells.Inindustrial
scalebakeries,automaticdepanningmaynothelpeliminatethisproblem.
BreadandOtherFermentedProducts
Chapter|4
217
4.2.7Wearemakingafruitedbunproductandfromtimeto
timeexperienceproblemswiththeproductflowingoutduring
proofandbaking.Canyouidentifythecauseandsuggest
aremedy?
Thereareanumberofpossiblereasonsforyourproductflowingduring
proofandbaking.Theyincludethefollowing:

Toomuchwaterinthedough.Thismaycomefromincorrectlevelsof
additionorfromthefruitifyouhavebeensoakingit.

Thepresenceofthereducingagentglutahionearisingfromthedisruption
ofyeastcellwhichhavenotbeenstoredcorrectly(see
Section2.7.9
).

Toomuchhumidityintheproverwhichcausessolubilisationofthepro-
teinsinthedough.

Residualsulphurdioxideinthedriedfruit(see
Section4.2.5
).
Astheproblemisassociatedwithafruitedproduct,wesuggestthatyou
thoroughlywashanddrythefruitbeforeusingit.Iftheproblempersists,then
youshouldlookforaprocessingcause,suchasexcesshumidityintheprover.
218
BakingProblemsSolved
4.2.8Whenwecutopenbreadrollsandhamburgerbuns
whichhavebeenstoredinthedeepfreezeforaperiodoftime,
weobserveawhiteringjustinsidethecrustwhichhasahard
eatingcharacter.Wheredoesthisproblemcomefrom?
Thephenomenonthatyouhaveobservediscommonlyreferredtoasfreezer
burnandarisesfromthemovementofwaterwithinandfromtheproduct
whilestillinthedeepfreeze.Thistypeofproblemwasreportedby
Pence
whoexaminedthewhitenedareasofproductsexhibitingthe
phenomenonandobservedthattheyhadagreaternumberoftinyvoidsasso-
ciatedwithstarchgranules.Thesevoidswherelinkedwithicecrystalswhich
hadsublimatedfromwithinthestarchgranulescausingagreateropacityof
thecrumbandthewhitenedappearanceduringfrozenstorage.Thechangein
thecrumbtexturefromthiseffectalsocausesthecrumbtohaveaharsh,dry
eatingqualityarisingfromthelowermoisturecontent.However,theeffect
doesnotcomeexclusivelyfromthelossofmoistureastheattemptsto
restorethecrumbpropertiesarelargelyunsuccessful.
Eventhough,theproducthasbeenstoredinadeepfreezerunningat
about
2
20

Cnotalloftheaqueousphaseintheproductisfrozen.This
arisesbecauseoffreeze

concentrationeffectsandthepresenceofsoluble
materialslikesaltandsugar.Aswate
rturnstoicecrystals,theconcentra-
tionoftheremainingaqueousphaseintheproductincreases,andits
freezingpointbecomeslower(
CauvainandYoung,2008
).Eventually,
theconcentrationmaybecomesolowthatthesolutionwillnotfreeze
evenat
2
20

C.
Anyincreaseintheproducttemperatureduringstoragewillenablesome
oftheunfrozenwaterpresenttodiffusefromtheproductintothesurround-
ingatmosphere.Thisclearlyhappenswithmanyfrozenproducts,asitisnot
commontofindsnoworicewithinthewrappingmaterial.Thelongerthe
productisheldinthestoragefreezer,thegreateristheaccumulationof
snowastheproductprogressivelydehydrates.
Aftertheproducthaswarmedinthestoragefreezer,anysubsequent
refreezingwilltakeplaceveryslowlyfromthesurfaceinwards.Thiscreates
aninterestingeffectbecausethecentreoftheproductoftenremainsfrozen;
surfacefreezesslowly.Theendresultistheformationofthewhiteareasof
freezerburnwhichcommonlyreflecttheoutershapeoftheproduct.
Theproblemcanbeminimisedbypayingattentiontoafewsimple
housekeepingrules:

Donotstoretheproductforverylongperiodsoftime.

Checktheactualstoragetemperatureoveraperiodofrunningtime.The
BreadandOtherFermentedProducts
Chapter|4
219

Ensurethatyourstoragefreezerisregularlyservicedandhavethecondi-
tionsofanyautomaticdefrostcycleschecked.

Asmuchaspossibleavoidactionswhichallowthefreezertemperatureto
riseexcessively.Forexample,keepdoorsclosedasmuchaspossibleand
minimiseloadingandunloadingtimesasmuchaspracticallypossible.
References
Cauvain,S.P.,Young,L.S.,2008.BakeryFoodQuality&Manufacture:WaterControland
Effects,seconded.Wiley-Blackwell,Oxford,UK.
Pence,J.W.,Standridge,N.N.,Black,D.R.,Jones,F.T.,1958.Whiteringsinfrozenbread.
CerealChem.35,15

26.
220
BakingProblemsSolved
4.2.9Wearenotalargebakerybutareplanningtopart-bake
andfreezebreadproductsforbake-offatsomelatertime;
whatpointsshouldwebeawareof?
Thebake-offoffrozenbreadproductsgivesbakersflexibilityofsupplyto
theircustomers.However,infreezingandbaking-offsuchproducts,itis
importantthattheyloseaslittlemoistureaspossibletoreducetherateat
whichthefinalbakedproductwillfirm(stale).
Whencoolingtheproductsaftertheirfirstbaking,thecoretemperature
shouldbechecked.Atemperatureof30

Cshouldbeaimedforinorderto
reducethethermalshockthattheproductswillexperiencewhentransferred
tothefreezer.Ittakessometimeforheattobedrawnoutfromtheproduct
breadtoambienttemperatureinthebakeryratherthanputhotbreadin
thefreezer.Coveringtheproductscanhelptoreducemoisturelossesbut
finalcrustquality.
achest-typefreezer.Thespeedoftheairmovementinablastfreezercan
removeasmuchas2

3%moisturefromtheproduct.Tolimitmoisture
losses,keepthefreezingtimesasshortaspossible.Productcoretempera-
turesafterfreezingshouldbeintheorderof
2
10

C,butrememberthatpro-
atdifferentrates.
Considercollatingracksbefore
loadingandunloadingthefreezer

i.e.,fewerdooropenings

orfittinganaircurtain.Openingtheblast
freezerdoorreducesitsefficiencywh
ichmeansthattheproducttakeslon-
gertofreezeandlosesmoremoisturetothebakeryatmosphere.Oncethe
mintomoisture-impermeablebags
andintoastoragefreezerasquicklyaspossibletoavoidmoisturelosses.
Thesaltinthebreaddepresse
sthefreezingpointtoaround
2
4to
2
6

C
andsooncethetemperaturerisesabovethis(forexample,duringpacking)
theproductbeginstodefrost.Partiald
efrostingandthenrefreezingresults
infreezerburn;thisshowsaswhitepatchesinthecrumbwhicharehard
tothetouchandhaveaharshmouthfeel(see
Section4.2.10
).Thephysical
andchemicalchangeswhichhaveoccurredinthecrumbarenotusually
reversiblesoyouneedtotakecareofyourstorageconditionsifyouareto
avoidthisproblem.
Anothercommonproblemwithfrozenbake-offproductisthatcalled
(
Fig.4.20
).Thisphenomenonarisesbecausethedifferentmoisturecontent
ofthecrustandcrumbcausethetwocomponentstofreezeanddefrostat
BreadandOtherFermentedProducts
Chapter|4
221
differentrateswhichstrainsthephysicallinksbetweenthetwo.Theprob-
lemcanoccuratanumberofstagesofthebake-offprocessdependingon
itsseverity.

Duringfrozenstorage,especiallyiftheproductisstoredforlongperiods
oftime.

Ondefrostingbeforesecondbaking.

Aftersecondbaking.
Withprolongedstoragetimes,youmayseeacombinationofshellingand
freezerburn.
Inpreparingtheproductforbake-off,checkthecoretemperatureon
defrostinginambientconditions.Aimforatemperatureof
2
5

C(just
defrosted).Atbake-offconsiderusinghighertemperaturesthanforstandard
bakingwithshorterbaketimes.Moisturelossduringsecondbakedepends
moreontimethanontemperatureandsoaccuratetimingofbake-offis
essentialiftheproductisnottolosetoomuchmoisture.Bake-offproducts
willalwaysstalefasterthanscratchproductsandexcesslossofmoisture
(eitherinthefreezingorthebakingoff)willexacerbatethisstaling(
Cauvain
andYoung,2008
).
Reference
Cauvain,S.P.,Young,L.S.,2008.BakeryFoodManufactureandQuality;WaterControland
Effects,seconded.Wiley-Blackwell,Oxford,UK.
FIGURE4.20
Shellingoffrozenbake-offproducts.
222
BakingProblemsSolved
4.2.10Whenwereheatpar-bakedproductswefindthatthey
remainsoftforonlyashortperiodoftime,typicallyanhouror
so,buttheyquicklygohardandbecomeinedible.Ifwedonot
reheatthem,wefindthatpar-bakedproductscanstayfreshfor
severaldays.Whatcausesthechangeintherateoffirming?
Isittheadditionalmoisturelostonthesecondbake?
Yourassumptionispartlycorrect.Moisturewillbelostfromtheproductsat
bothbakingstages,anditismorethanlikelythatthesumofthetwomois-
turelosseswillexceedthatofasinglebake.Thelowerthemoisturecontent
oftheproduct,thefirmerthecrumb.However,tofullyansweryourquestion
weneedtoconsidertheprocesswhichcerealscientistscallstaling.
Breadcrumbfirmnessincreasesduringstorageevenwhennomoistureis
lostfromtheproduct.
SchochandFrench(1947)
proposedthemostcom-
monlyacceptedmodelforbreadstaling.Theirmodelforbreadstalingwas
basedonthechangesinthetwomajorfractionsofthestarchinwheatflour,
theamyloseandtheamylopectin,post-bakingandduringstorage.Rawstarch
granulesinflourhaveanorderedorcrystallinestructureandduringdough
mixingthosewhichhavebeenphysicallydamagedduringflourmilling
becomehydrated.Inthedoughenteringoventhestarchfirstswellsasit
absorbswaterandthenlatergelatinisesasthetemperatureincreasesto
around60

65

C.Gelatinisationdisruptsthecrystallinestructureandthe
amylosediffusesintotheaqueousphasetoformaninsolublegelwhichcon-
tributestoasoftcrumbstructure.Onleavingtheoventhebreadcoolsand
theamylosefractionquicklyre-associates;thisprocessgivesbreadcrumbits
initialfirmness.Theotherstarchfraction,theamylopectin,takesmuchlon-
gertore-associate,usuallyseveraldays.Itisthisprocesswhichisresponsi-
bleforcrumbfirmingduringprolongedstorageandistheonemost
commonlyassociatedwithbreadstaling.
Ifstalebreadisreheateditispossibletoreversetheamylopectinrecrys-
tallisationprocessandsoftenthecrumb.However,whenthebreadscoolthe
secondtime,thereisanoticeableincreaseintherateatwhichitgoesfirm;
whatusedtotakedaysnowtakesonlyafewhours.Thisincreasedstaling
rateisassociatedwiththetemperaturethattheproductachievesduring
reheating.Itisessentialtomelttheentireamylopectinfractionintheproduct
whichmeansthatthecentrecrumbtemperatureshouldreach65

C.Ifthis
doesnothappenthenafewun-meltedcrystalsofamylopectinactasseedfor
therecrystallisationprocesswhichproceedsmuchfasterasaresult.Many
usersarecautiousaboutre-heatingbake-offproductsandareconcernedto
avoidexcesssurfacecolour,consequentlythecrumbdoesnotreachthecriti-
caltemperatureandre-firmingratescanberapid.
Reference
Schoch,T.J.,French,D.,1947.Studiesinbread
staling.1.Roleofstarch.CerealChem.24,231

249.
BreadandOtherFermentedProducts
Chapter|4
223
4.2.11Whilereadingaboutthemanufactureofhamburger
buns,weseereferencestothepHandTTAofthebrew.
Whatdothesetermsmean?Whenaretheyusedand
whatisthepurposeofcontrollingthem?
Inthemanufactureofhamburgerbuns,itisacommonpracticetopre-ferment
partoftheflourwithwaterandyeastbeforeaddingthemixturetothe
remainingingredientsformixingintothefinaldoughandprocessinginto
buns.Thispre-fermentationstagehasanumberofadvantagesincludingthe
modificationoftherheologicalpropertiesofthefinaldoughwhichassist
inimprovedprocessingandflowoftheshapesinthepan.Theotherimportant
changewhichoccursasaresultofthepre-fermentationstageisthedevelop-
mentofacidicflavournotesinthefinalproduct.
Duringpre-fermentationtheacidityofthedoughfallsandsothepH(see
Section10.1
)ofthebrewfalls.However,themeasurementofpHalonedoes
notprovidethenecessaryinformationontheformationofacidsinthebrew,
anditiscommonpracticetomeasurethetotaltitratableacidity(TTA).The
TTAtestmeasuresboththedissociatedacids(whichdirectlyimpactpH)and
theun-dissociatedacidsunderspecifiedconditionsandprovidesrelevant
informationontheexpectedflavourprofileinthefinalbakedproduct.
Inbroadterms,thetwopropertiesarerelatedinthattheTTAofabrew
increasesasitspHfalls.However,oneoftheproblemsassociatedwithusing
pHasthesolepredictorofthedegreeoffermentationinthebrewisthat
someoftheingredientsthatmaybeusedinbakinghaveabufferingeffectin
thebrew.Thepresenceofbufferingagentsmeansthateventhoughthe
amountsoforganicacidsinthebrewincrease,thehydrogenionconcentra-
tion(pH)doesnotsignificantlydecrease.Inanumberofpartsoftheworld,
themandatoryorvoluntaryadditionofcalciumcarbonatetowheatflour
introducesasignificantbufferingagent.
ItisworthnotingthatchangesinbrewpHandTTAarenotexclusively
controlledbybakersyeastfermentation.Thepresenceof
lactobacilli
and
otherlessdesirablemicroorganismsintheflourcanmakesignificantcontri-
butionstothegenerationoforganicacids.Regularcleaningoutofthebrew
tanksisessential.UnexpectedchangesinTTAinthebrewcanoftenbean
indicatorofthepresenceofhighlevelsofunwantedmicroorganismscanbe
animportantindicatoroftheneedtocleanoutthebrewsystem.
Furtherreading
Cauvain,S.P.,2015.TechnologyofBreadmaking,thirded.SpringerPublishingInternational
AG,Switzerland.
224
BakingProblemsSolved
havelargeholesunderneaththetopcrust.Wedonotexperience
thesameproblemwithscratch-madeproducts.Whyisthis?
Eventhoughyouarenotexperiencingaproblemwithyourscratchproduc-
tiononeofthepossiblecausesofy
ourproblemmaycomefromtheshap-
ingprocesses.Inparticular,thepressureappliedduringthepinning
structureunderneaththeuppersurfaceofthedough.Thedoughpieces
tionmaytendtoexaggeratetheproblemthatmightbeseenonsomeocca-
sionswithscratchproduction.
Someofthecausesofdamagetothegasbubblestructureinthedough
cancomefromtheinitialdoughmixingandprocessing.Forexample,ifthe
doughisstiff(lackswater)orcoldthenpinningpressuresneedtobehigher
toachievetherequiredshapeandsize.Thereisoftenatemptationtomake
lessabletowithstandthestressesandstrainsappliedduringprocessing
lowerdoughtemperatures.
canalsobemadeworseifanyskinningofthedoughpiecehastakenplace
butifthisistoogreat,theuppersur-
faceofthepiecelosesflexibility.Whenthepiecemovesintotheproof
cycletheincreasedevolutionofcarbo
ndioxideinthedoughincreasesthe
internalstresseswithinthepiece.T
hismayexploitanyareasofweakness
ningislesslikelytooccurwiththescratchproducttheuppersurface
ocopewiththeinternalstressesand
strainsandperhapsexplainswhyyoudonotseetheproblemwithscratch-
madeproducts.
Furtherreading
Cauvain,S.P.,2015.TechnologyofBreadmaking,thirded.SpringerPublishingInternational
AG,Switzerland.
BreadandOtherFermentedProducts
Chapter|4
225
findthattheproductsmadebakedfromthemarecoveredwith
manysmall,white,almosttranslucentspotsonthesurface.We
thesamerecipe.Canyougiveanexplanationfortheir
Theformationofsmall,white,almosttranslucentspotsonthesurfaceof
Fig.4.21
).Theprinciplereasonsfor
theproductionofcarbondioxidegashasbeenshowntocontinueindough
evenwhenstoredat
2
5

overthelongstorageperiodbeginstoinflatethesmallgasbubblesinthe
dough.Whenviewedunderalowpowermicroscopethelargergasbubbles
heldjustunderneaththetopsurfaceofthedoughpiecewherewhitespots
freewatermayactasadiluentforthecolour-formingcomponentswhich
normallycontributetocrustcolourandsoonbakingthoseparticularbubbles
roleofmoistureisindicatedbythefactthatwhitespotscannotoccuron
FIGURE4.21
BreadandOtherFermentedProducts
Chapter|4
227
Eliminationofthewhitespotscanbeachievedinanumberofdifferent
waysincluding:

choiceofasuitableimprover.

Bynotusingalowdoughtemperature.Eventhoughitistemptingtouse
alowdoughtemperaturetocontrolyeastactivity,thisactionwillreduce

Byreducingyeastleveltominimisegasproductionintheearlystagesof

doughpiece.

Furtherreading
Cauvain,S.P.,2015.TechnologyofBreadmaking,thirded.SpringerPublishingInternational
AG,Switzerland.
228
BakingProblemsSolved
andbuns.Wefindthatthesmallerproductsarequite
satisfactorybutloavesmadeusingthesameformulationand
bakedinpanshavestainsaroundthefruitpiecesandadarker
crustcolourthanwewouldlike.Canyoupleaseadviseuson
howtocuretheseproblems?
productsaremadewiththesamedoughformulation.Thedifferencesarise
becauseittakeslongerfortheheattobeextractedfromthecentreoflarge
doughpiecesthanitdoesfromsmallerones.Inyourcase,thepanloaves
slowdownyeastactivityinthedoughsothatitmaybestoredforextended
periodsbeforelaterwarmingandbaking.
Inadditiontoyeastactivity,therewillbesignificantenzymeactivityin
thedough.Inparticular,theamylaseenzymeswillbereactingwiththedam-
agedstarchintheflourandconvertingthemtomaltose.Withthelongstor-
suchactivity.Themaltosewhichisproducedeffectivelyincreasesthelevel
ofsugarsthatarepresentinthedoughwhenitreachestheovenandthis
givesincreasedMaillardbrowning(see
Section4.1.14
)whichisthecauseof
thedarkercrustcolourthatyousee.Tominimisethecrustcolourincrease,
temperaturesaround
2
4

C.Thedoughwillnotfreezebecausethepresence
ofsaltandsugardepressthefreezingpoint.Youwillhavetostartyour
proofingphasealittleearliertoallowfortheslightlycolderdough.
Iftheabovesuggestionsdonotwork,thenyoumayhavetomakeyour
bunsloavesusingaformulawithaslightlylowersugarlevel.Anotherchange
whichtakesplaceinyourproductsisthegradualseepageofsugarsfromthe
fruitintothesurroundingdough.Thisoccursbecausethefruitandthedough
havedifferentmoisturecontentsandwateractivities;first,watermovesfrom
thedoughtothefruitpieces,thenthesugarsdissolveandthesugarsolution
diffusesoutofthefruitbackintothesurroundingdough.Thesugarscoming
outofthefruitaredifferentfromthesucrosethatyouhaveaddedandwhen
theyareheatedtheygobrownatlowertemperatures

hence,thestainson
thesideoftheloaveswheretheheatinputsaregreater.
Thisproblemwillbedifficulttoeliminatebutagainloweringtheretard-
ingtemperaturewillreducetheratesofmoisturetransferanddiffusionof
thesugarsolution.Alternatively,youcouldwashthefruittoreduceits
sugarcontent,drainofftheexcessmoistureandallowthefruittodrybefore
usingit.
BreadandOtherFermentedProducts
Chapter|4
229
thattheyleantoonesideandloseweightduringstorage.
Canyouadviseusastohowtocuretheseproblems?
Alldoughproductslosesomemoistureduringstorageduringretarding,and
thisaccountsforthelossinweightthatyouareexperiencing.Theweightloss
occursbecausetherelativehumidityofthedoughpieces(typicallyaround
95%)isgreaterthanthatoftheatmosphereintheretarderandthereisevapo-
rationofmoisturefromthedoughsurface.Tomaintainahighrelativehumid-
ityintheretarderchamber,theevaporatorcoilsurfaceismuchlargerthanin
standardrefrigerator.Thisreducesthelikelihoodofmoistureintheretarder
chambercondensingoutandformingiceonthecoolingcoils.Moisturewhich
condenseslowerstherelativehumidityofthechamberatmosphereand
increasesthedifferentialbetweenthechamberairandtheproductsothatthe
latterwillcontinuetolosemoistureinanattempttoachieveequilibrium.
ingtemperaturetobelow0

Cbutkeepitabove
2
5

C,e.g.,around
2
3

C,
tominimiseweightlosses.Youmayfinditnecessarytogiveaslightlylon-
gerproofperiodtocompensatefortheslightlycolderdoughbutthediffer-
enceshouldonlybeafewminutes.Loweryeastlevelsalsoleadtolower
weightlossesfromthedoughpieces,whateverthestoragetemperatureused.
Ifyoudodecidetouseloweryeastlevels,thenyouwillcertainlyneedto
Anotherfactorwhichcontributestoweightlossesisthemovementofair
theyarejustsufficienttomaintainuniformityofthechamberairtempera-
tures.Highairvelocitieswillleadtodehydrationofthedoughpiecesthough
yeastlevels.
Theproblemthatyouhavewithdoughpiecesleaningislinkedwiththe
weightlossesthatyouareexperiencing.Ifyoulookclosely,youwillnotice
andimpingesonthedoughpiece,itdrivesoffalittlemoisturefromthefirst
surfacethatitencountersbutdrivesoffrelativelylittlemoisturefromthe
surfacesofthedoughontheothersideoftheroll

justaswenoticeless
airmovementwhenwestandintheleeofahillonawindyday.Thedehy-
dratedsurfacelosesitsflexibilityandcannotexpandwhencarbondioxide
Furtherreading
Cauvain,S.P.,2015.TechnologyofBreadmaking,thirded.SpringerPublishingInternational
AG,Switzerland.
230
BakingProblemsSolved
severaldays;toachievethisweareusingarollconcentrate.
Tohelpuscopewithfluctuationsindemandwefreezea
proportionofourproduction,butfindthatthedefrosted
productisveryfragileandmayevenfallapart.Canyouhelpus
overcomethisproblem?
Inadditiontothefragility,youareexperiencingthesamplesthatyouhave
provided,weseethattheyallhaveaverycoarsecellstructureandadull,
almostdark,crumbcolour.Theproductswerecertainlyverysoft,butthere
wasnoresiliencetothecrumbwhichhadapastyeatingquality.Akeyfactor
indeliveringasoftandresilientcrumbisthedevelopmentofafineandrela-
tivelyuniformcellstructureintheproduct;fromourobservationsonyour
productthisisnothappening.Anumberofdifferentfactorswillcontribute
todoughdevelopment;theyincludethechoiceofflour,rollconcentrate
(improver)andmixingconditions.
Yourproductrangeisbasedonwhiteflourbutincludesseveralvariations
tiesofthedough;ineffect,youareaskingtheflouryouareusingtocarry
someinertmaterials.Asabasicchoice,youshoulduseaflourwithaprotein
contentof12

12.5%(ona14%moisturebasis)withalowashorgradecol-
ourfigure(see
Sections2.2.1and2.2.2
).Theproteinisthebasicbuilding
blockofdoughdevelopmentandwillcontributetothecrumbresilience
whichyourproductslack.
Havingchosenasuitableflour,itisjustasimportanttochoosea
Itturnsoutthatyouareusingaspiralm
ixerwithacombinationof2minutes
mixingonslowspeedand4minutesinfastspeed.Youshouldincreasethesec-
ondspeedmixingstagetoatleast8andeven10minutes.Youcancompensate
fortheslightlyhigherdoughtemperatur
ebyusingalowerwatertemperature.
Fromtheinformationthatyouprovided,itwouldbeperfectlyreasonable
touseaslightlyhigherdoughtemperatureasthiswillincreasetheoxidation
potentialoftheAAinyourrollconcentrate.Currently,yourdoughtempera-
tureisonly22

24

C,youcancertainlyincreasethisto26

28

C.Ifyou
experienceproblemswithexcessgassingduringprocessingslightlyreduce
thelevelofyeastinyourrecipe.
Ifyouoptimiseyourchoiceofflouranddoughmixingconditions,you
mayfindthatyoucanreducethelevelofrollconcentratethatyouuse.The
componentsintherollconcentratethatmakecontributionstocrumbsoftness
arethefat,emulsifiersandsomeoftheenzymespresent;currently,youare
relyingonthesetodeliverasoftproduct,butyoushouldseetheseasa
top-uptobasicdoughdevelopmentnotanalternativetoit.
BreadandOtherFermentedProducts
Chapter|4
231
breadsandtheirproduction?Wemakeourstandardbreads
usingtheChorleywoodbreadprocess,wouldwebeabletomake
theseproductsusingthisprocess?
Chinesesteamedbreads,orman-tou,areknowntohavebeeneateninChina
foraround3000years.Theyareastaplefoodofthewheatgrowingareasof
northernChinabutareconsumedthroughoutthecountry,commonlywarmat
breakfastthoughtheyareoftenavailableatallmealtimes.Theyareknownin
manyothercountriesthroughoutsouth-eastAsiaandincreasinglyfurtherafield.
Itderivesitscommonname,steamedbread,fromthecharacteristic
productwithasmooth,white,thincrust.Externallythesurfaceshouldbe
freefromblemishes.Internally,theproductshaveaclosecellstructure,
brightcrumbcolourandadistinctlychewyeatingcharacter.Theproductis
eatenwarm.Thetraditionisfortheproducttobefreshlymade,oftenusing
overnightfermentationsothattheproductisreadyforbreakfast.
amixtureof100partsofalowproteinbreadmakingflour,0.5partsyeast
and50

55partswater;thereisnosaltintherecipe.Thedoughisthor-
oughlymixed(commonlybyhand)andfermentedfor3

16hours.Theyeast
levelmaybeadjustedtouselessforthelongerfermentationtimes.Should
thedoughsoftenexcessivelyduringthefermentationtimethenmoreflour
maybeadded,thedoughre-mixedandthenallowedtostandforabout
another15minutesbeforeprocessing.
Afterfermentationthebulkdoughisdividedinto100

200gpiecesand
eithermouldedroundortoaroughcylindricalshape.Ashortproofperiodof
about15minutesisgivenbeforetransferringthepiecestothesteamerwhere
theyaresteamedfor15

20minutessuspendedonwiremeshtrays.Thespe-
cificvolumeofthefinalproductismodest,typicallyaround2.0mL/gwhich
ismuchlowerthanthatofUKpanbreads(around3.5mL/g).
TheapplicationoftheCBPtotheproductionofChinesesteambreadhas
beenstudiedandfoundthatitwaspossible.
CauvainandYoung(2006)
pub-
Ingredient%Flourweight
Untreatedflour100
Compressedyeast1
Water60
Ascorbicacid0.0075(75ppmflourweight)
232
BakingProblemsSolved

Thedoughwasmixedatatmosphericpressuretoatotalof11Wh/kg
doughinthemixer.

Finaldoughtemperature30
6
1

C

Scaleat100or200g.

Mouldround

Nointermediateproof.

Proveat40

Cand85%relativehumidity;15minutesfor100gand
30minutesfor200gpieces.

Steamfor15

20minutes.
SomeoftheconventionalCBPrecipeandprocessingparameterswere
notsuitableforthemanufactureofChinesesteamedbread.Oneofthe
reasonsforthesefindingswasprobablyrelatedtothelowproductspecific
volumethatwasexpected.Insummary,theirkeyfindingswereasfollows:

Theoptimumflourproteinwasaround10%(ona14%moisturebasis);
higherproteinflourstendedtocauseproductcollapse.

HighlevelofAAcausedproductcollapse.

Theadditionoffatcausedsmalldepressionsontheproductsurface.

Workinputsoflessthan11Wh/kgresultedincavitiesunderthetopsur-
faceoftheproduct,whilehigherlevelcausedproductcollapse.

Highcereal
alpha
-amylasecauseddoughhandlingproblemsandproduct
collapse.
Insummary,theirfindingsshowedthatChinesesteamedbreadmadeby
theCBPrequiredlittlebywayoftheadditionofdoughconditionersorbread
improverstodelivertherequiredproductquality.
Moststeamedbreadproductscallforawhiteflouressentiallyfreefrom
branparticleswhichwouldotherwisespoiltheappearanceofthecrust.
However,notallsteamedbreadsarebasedonwhitewheatflour;onevaria-
tionismadeusingaproportionofbuckwheatflourwhichyieldsaproduct
withadistinctiveflavourandevenmoredistinctivepurplecolour.
Reference
Cauvain,S.P.,Young,L.S.,2006.TheChorleywoodBreadProcess.WoodheadPublishingLtd,
Cambridge,UK.
BreadandOtherFermentedProducts
Chapter|4
233
4.2.19Whatiscinnamontwistbreadandhowcould
wemakeit?
Thedistinctivefeatureofcinnamontwistbreadisthatitpreparedbyspread-
Chapter5
Cakes,SpongesandMuffins
CAKEMAKING?
involvessplittingtheflourintotwoportions,thefirsttobecreamedwiththe
fatsandthesecondportiontobemixedintothebatteratalaterstage.Atthe
sametimeastheflourandfatarebeingmixed,theeggsandsugarare
whiskedtogetherusingasecondmachinetoformafoam(similartothepro-
ductionofspongecakes).
Typically,thefatsarecreamedwithanequalweight(orslightlyless)of
flouruntilacreamymixtureisobtained.About400gflourto450gfat
(14ozflourto1lbfat)isrecommended.Theeggiswhiskedwithitsown
weightofsugar.Thiswhiskingneednotbeasthoroughasforspongecakes,
andaerationshouldnotgotoofarorthecakeswillbetoolargeinvolume
andhaveafriablecrumb.About5or6minutesonsecondorfastspeed
Section5.2
).
Whentheegg

sugarfoamisready,itisaddedtotheflourandfatbatter,
whilethemachineisrunningatamoderatespeed.Thefoammaybeadded
insmallportions

Usuallyinfourorfiveparts,eachportionbeingbeaten
inbeforethenextportionisadded.Alternatively,itmayberuninasacon-
tinuousstream.Whenbothbattersaremixed,anyremainingflourandbak-
ingpowdercanbemixedin,eitherbyhandorattheslowestmachinespeed.
Forfruitedcakes,thefruitisaddedwhentheflourisalmostmixedin.
Anyminoringredientssuchasessencesorcoloursshouldbeaddedtothefat
andflourwhilebeating.Ifmilkisadded,thenthisshouldbedoneatthe
timeofaddingthesecondportionofflour.Wheretheweightofsugaris
greaterthantheweightofeggs,theextrasugarshouldbedissolvedinthe
thecolourthroughoutthecakebatter.
235
BakingProblemsSolved.DOI:
http://dx.doi.org/10.1016/B978-0-08-100765-5.00005-9

2017ElsevierLtd.Allrightsreserved.
Ifglycerineisusedinflour-battercakes,thismaybeaddedtoeitherthe
spongeortotheflourbatter,usuallythelatterbeforethetwoaremixed
together.Whenmilkpowderisusedinsteadofliquidmilk,thenecessary
quantityofpowderisaddedalongwiththesecondportionofflour,whereas
thenecessaryamountofmoistureintheformofwaterisaddedandthebat-
terismixedasbefore.
theeggstooquicklycanresultincurdling(see
Section5.3
).Anotheradvan-
sugar,amoreeventextureisimpartedtothecake.Asmostoftheflourhas
beencreamedwiththefats,thereisrelativelylittleofittobeamalgamated
atthecriticalmomentincakemakingafteralltheeggsarein,sothepoten-
tialfortougheningofthebatterbyoverworkingisreduced.
Alloftheingredientsshouldbeatthesametemperaturebeforemixing
startstoensurethatasuitabletemperatureisachievedinthefinalcakebat-
ter,typicallyaround20

C.
waterprooftheflourbyblendingitwithfatandsolimitingthepotential
developmentofglutenstructureinthebatter.Infact,theformulationofcake
asseeninbreaddough,isunlikely.
236
BakingProblemsSolved
CAKEMAKING?
ofoil/fatinwaterwithairbubblestrappedinthesolidfatphase.Theother
ingredientsaredissolvedordispersedinthewaterphase.Thefatsandsugar
arecreamedtogetheruntilthemixtureislight.Usually,thistakesabout10
minutesbutdoesdependonthetemperatureandcreamingqualitiesofthefat
andthetypeofmixerused.Youwillnotbeabletoachievethedesiredresult
usingonlyliquidoil.Manycommercialbakersmixthebattertoafixed
specificgravity(see
Section10.2
).Theliquideggisthenaddedinfourorfive
portionsoveraperiodof5to7minuteswithcreamingofthemixturebetween
additionstopreventthebattercurdling.Egg,andtheotheringredients,should
beatthecorrecttemperature(typically,21

C/70

Fisconsideredoptimum)as
thiswillalsoassistinavoidingcurdlingofthebatter(see
Section5.3
).
Once,alltheeggshavebeencreamedin,thebattershouldhavea
siftedflourandallotherpowdersandanyadditionalmilkorwater.These
aregentlymixedintothebatter.Anyfruitshouldbeaddedwhenclearing
thebatter(i.e.,thelaststagesofmixingtoensurethattherearenounmixed
ingredientsremaining).Itisnotadvisabletomixthefruitwiththeflouras
someflourmaysticktothefruitandcouldcausetheformationoflarger
holesinthebakedcake.
Itisimportantinallcakemakingprocessestohavecorrecttemperatures
andmixingconditionstoensureconsistentproductquality.
Cakes,SpongesandMuffins
Chapter|5
237
5.3WHYDOOURCAKEBATTERSMADEBYTHESUGAR-
5.4WEAREEXPERIENCINGSOMEVARIATIONINCAKE
QUALITY,ESPECIALLYVOLUME.HOWIMPORTANTISITTO
CONTROLTHETEMPERATUREOFOURCAKEBATTERS?
Almostalloftheprocesseswhicharecriticaltosuccessfulcakequalityare
initiatedinthemixingstages,sotomaintainconsistentbatterandfinalcake
qualities,itisimportanttomaintainastandardbattertemperature.
Variationsincakebattertemperatureswillhavesignificantimpactonthe
followingprocesses:

Therateatwhichthesolubleingredients,mainlythesugarswilldissolve;
thelowerthebattertemperature,thelongeritwilltakeforthesugarsto
dissolve.Thiscanhaveaprofoundimpactwhenusingcoarsergrained
sugarssuchasthegranulatedformandcancontributetotheformationof
whitespotsorspecklesonthebakedcake(see
Section5.19
).

Therateatwhichthestarchintheflourwillhydrate;thelowerthebatter
temperaturetheslowerthestarchwillbetohydrate.

Thecreamingandaerationpropertiesofthefat;ingeneral,thelowerthe
battertemperaturesthepoorerthecreamingpropertiesofthefatin
Section5.2
)andthelowerthe
case,thebakedcakesmaylackvolumeandhavepooreatingqualities.
However,thepreciseimpactoftemperatureonfatperformancedepends
whichmakeupthefat(see
Section2.3.1
).

Thefunctionsofemulsifiersusedtoaidbatteraerationwillbeaffected.

Therateatwhichthebakingpowdercomponentswillreact.Allchemical
reactionsproceedmoreslowlywhenthetemperaturefallsorproceed
morerapidlywhenthetemperaturerises.Ofallofthepotentialimpacts
ofvariationsincakebattertemperaturetheimpactonbakingpowder
reactionsisperhapsthemostimportantone.Variationsintherateof
releaseofcarbondioxidefromthebakingpowderreactionhavedirect
impactsoncakeshape,volumeandstructure(see
Section2.6.9
).

Thecontrolofbatterdepositweightwillbemoredifficulttoachieve
becauseofvariationsinbatterdensitylinkedwithfatandemulsifierper-
formanceandbakingpowderreactionratesfrombatchtobatch.
Insummary,youcanexpectthatvariationsinthetemperatureofthe
batterthatyouproducewillbeassociatedwithvariationsincakeshape,
volume,appearanceandstructure.
Cakes,SpongesandMuffins
Chapter|5
239
5.5HOWDOWECALCULATETHELIKELYTEMPERATUREOF
OURCAKEBATTERATTHEENDOFMIXINGANDWHAT
TEMPERATURESHOULDWEAIMFOR?
Thepredictionofthebattertemperatureattheendofmixingisrelatively
straightforwardbecausethemaininputstothecalculationcomefromthe
temperaturesoftheingredients.Cakeandotherbattershavearelativelylow
viscosityandtheirlowresistancetomixingmeansthatrelativelylittleheat
isgeneratedinthemixingprocess.Theremaysomeinfluencefromthe
ambienttemperatureandequipmenttemperatures,butthisisusuallycon-
finedtotimeswhenthereareextremesoftemperature,e.g.,oncoldstart-up.
Tocalculatethelikelycakebattertemperature,youneedonlypreparea
simpletableoftheingredientcontributionsandcalculatetheweightedaver-
age.Duetothehighlevelofwaterpresentinvariousformsintheformula-
tion,itislessimportanttotakeintoaccountthespecificheatcapacityofthe
variousingredientsthanwouldbethecasewithbreaddough.Thefollowing
examplewillhelptoillustratetheprocess:
IngredientMass(kg)Temperature(
C)Mass
Temperature
Flour100252500
Fat50201000
Bakingpowder22550
Sugar110252750
Liquidegg304120
Water75151125
Total3677545
Battertemperature
temperature
totalmass
Ifyouwanttoachieveaconsistentbattertemperatureandwanttocom-
pensateforvariationsiningredienttemperaturethenwesuggestthatyou
adjustthewatertemperature.Thissimplymeanssubstitutingthetemperature
ofthewaterintheabovetablewithanunknown,sayTandthenusethefol-
lowingcalculation:
Therequiredfinalbattertemperatureis20
C.Thus,
BakingProblemsSolved
where6420isthesum(mass
3
temperature)ofingredientswithoutthe
watercontribution.Rearrangingthisgives
T
5

367
3
20

2
6420
75
soT,therequiredwatertemperature
5
12.3

C.
Wewouldrecommendthatthefinalcakebattertemperatureintheregion
is18

24

C.Lowbattertemperaturesmayleadtocurdling(separation)ofthe
batter(see
Section5.3
),impairedperformanceofthefatandundulydelayed
releaseofcarbondioxidefromthebakingpowder(see
Section2.6.9
).
Allfloursexhibitaphenomenonknownasheatofhydration(
Wheelock
andLancaster,1970
);thatiswhenflourandwateraremixedtogether,there
isanincreaseinthetemperatureofthemixbeyondthecontributionofthe
individualingredients.Thedriertheflourthegreaterwillbetheheatof
hydration.Manyheat-treatedflours(see
Section2.2.17
)havemoisturecon-
tentssignificantlybelow14%,andthismeansthattheheatofhydrationcan
besignificant.Theheatofhydrationcanbecalculatedaccordingtothefor-
mulaprovidedbyWheelockandLancasterandshouldbedeductedfromthe
practice,theeffectsarerelativelysmallandseldomaccountforanincrease
inbattertemperatureofmorethan1

2

C.However,evensuchrelatively
smallincreasescanhaveaneffectontherateofreaction(ROR)ofthebak-
ingpowderandshouldbetakenintoaccounttominimisetheimpactonfinal
productquality(
CauvainandYoung,2008
).
References
Cauvain,S.P.,Young,L.S.,2008.BakeryFoodManufactureandQuality:WaterControland
Effects.Wiley-Blackwell,Oxford,UK.
Wheelock,T.D.,Lancaster,E.B.,1970.Thermalpropertiesofwheatflour.Starke22,44

48.
Cakes,SpongesandMuffins
Chapter|5
241
MANUFACTUREOFOURPLAINCAKES.OCCASIONALLY,WE
EXPERIENCELOSSOFVOLUMEANDTHETOPOFTHEBAKED
PRODUCTBECOMESPEAKEDRATHERTHANFLAT.ITHAS
BEENSUGGESTEDTHATWEAREOVER-MIXINGTHEBATTER
ANDDEVELOPINGTHEGLUTENINTHEFLOUR;ISTHIS
CORRECT?
First,itisratherdifficulttodevelopaglutenstructureincakebattersofsim-
ilarstrengthtothatseeninbreaddoughs.Therearetwomainreasonsfor
this;oneisrelatedtothenatureofcakeformulationsandtheothertothevis-
cosityofthebatter.Cakerecipestypicallycontainhighlevelsofsucroseand
othersugarswhichdissolveinthewaterpresentinthebatterandlimitthe
availabilityforhydrationofthegluten-formingproteinsintheflour.Some
(see
Section5.1
).
Thewaterlevelsincakebatterrecipeswithrespecttotherecipeflour
weightaresignificantlyhigherthanthatseewithbreaddoughrecipes;typi-
cally,therecipewaterlevelwillbeequaltothatoftheflourweightincakes,
whereasitseldomexceeds70%inbreaddoughrecipes.Thehighlevelof
recipewatersignificantlylowerstheviscosityofthebatterandreducesthe
abilityofmixingequipmenttotransferenergytothebatter.Inbreadmaking,
thesignificantresistanceofthedoughduringmixingisessentialforthe
transferofenergy,andasthefrictionalforcesarelowincakebatters,itis
cantroleincreatingyourproblem.
sibletomanufacturecakebattersinthisway.However,asalloftheingredi-
entsarepresentatthestartofmixing,allofthereactionswhichare
associatedwithcakemakingwillbeinitiated.Inthecontextofyourproblem,
animportantoneisthegenerationofcarbondioxidegasfromthebaking
powderthatyouareusing.Asthegasisgenerated,thecontinuedagitation
ofthebatterpermitstheescapeofaproportionofthecarbondioxideduring
themixingprocessitselfandthelongerthemixingtimethegreateristhe
potentialforthelossofcarbondioxidegas.
242
BakingProblemsSolved
Inessence,alongmixingtimeisdeliveringacakebattersimilarincon-
stituentstothatcontainingloworreducedlevelofbakingpowder;ifyou
lowvolumeproductsandapeakedshape.
Theobvioussolutionistoavoidover-mixingthebatterandworkwitha
fixedmixingtime.Youwillalsoneedtoensurethatyouarenotallowingthe
finalbattertemperaturetorisetoohighasthiscanalsocausepremature
releaseofcarbondioxide.Muchasyoushouldfixyourmixingtime,you
shouldfixyourfinalbattertemperature(see
Section5.4
).Ifyoucontinueto
haveproblems,thenyoumayconsiderchangingthecompositionofyoubak-
ingpowdertoonewithalowerROR(see
Section2.6.9
).
Cakes,SpongesandMuffins
Chapter|5
243
5.7WHENMAKINGFRUITCAKES,WEFINDTHATTHE
Olderrecipebooksshowthatbakershaveaddedasmallquantityof
groundalmondstothemixing.Duringbaking,thiswillhavesufficientbind-
ingandswellingeffecttocounteracttheforceofgravityactingonthefruit.
However,thiscanaddtothecostsoftherecipeandmaycauseotherpro-
Chapter|5
5.8CANWEFREEZECAKEBATTERSANDWHATHAPPENS
TOTHEMDURINGSTORAGE?
Cakebatterscanbefrozensuccessfullyandfrozencakebattersmaybepur-
chasedtoreducethewastagethatmightoccurwithscratchproductionwhere
consumerdemandisoftenlesspredictable.Forthosepurchasingfrozencake
batters,theadvantagesinclude:

Nostorageorhandlingofrawmaterials(apartfromproductdecoration).

Noingredientweighingormixingonsite.

Specialistcentralisedproductionimprovingthechancesofoptimalprod-
uctquality.

Cakebatterscanbefrozenandstoredforupabout2or3monthsbefore
anysubstantialqualitylossesinqualityofthefinalproductareencountered.
2
12and
2
20

C
(11and6

F).Thetemperaturewillvarydependinguponthelevelofdis-
solvedsaltsandsugarsbecausetheirpresencedepressesthefreezingpointof
thefreewaterinthebatter.Thehighsugarconcentrationinmostdriedfruits
willfurtherdepressthefreezingtemperatureoffruitedcakebatters.The
timetakentofreezethebatterwillbeshorteratlowerairtemperaturesand
higherairvelocitiesinthefreezer.
Careshouldbetakennottoexposethefrozenbattertotemperatures
unplannedthawingcanleadtodeformationofthebatterinthecontainer.
Somelossofvolumewilloccurwithcakesproducedfrombatterswhich
havebeendeepfrozenandstoredat
2
20

C.Thislossofvolumewillbeprogres-
sivewithincreasingstoragetime.Alongstoragetimewillalsoleadtoafirmer
andlesstendercrumbinthebakedpr
oduct.However,withcare,theproduct
shouldstillhaveacceptablevolume,crumbtextureandtastewhenbaked.The
crustofthecakemayhaveamarbleda
ppearanceduetothebatterdryingout
duringstoragecausinglocalisedexcesssugaratthesurfaceofthecake.
Thefrozenbattersshouldberemovedfromthedeepfreezeandcaneither
begivenashortdefrostingperiod,orbakedimmediatelyfromfrozen.The
surfacediscolourationmayoccurwhenproductisbakedfromfrozen,but
thismaynotbeadisadvantageifthecakeistobedecorated.Bakingcondi-
tionsshouldbeasnormalbutifbakingfromfrozenalongerbakingtime
mayberequired.
Furtherreading
Cauvain,S.P.,Young,L.S.,2008.BakeryFoodManufacture&Quality:WaterControland
Effects,seconded.Wiley-Blackwell,Oxford,UK.
246
BakingProblemsSolved
5.9WHYDOCAKESGOMOULDY?
Mouldgrowthisthevisiblesignthattheproducthasbeencontaminated
withmouldsporesinanenvironmentsuitablefortheirgrowth.Suchspores
canbepresentinthebatterbutareusuallykilledinthebakingprocess.
However,astherearemanysporesintheatmosphere,itislikelythatmould
Chapter|5
Itisimportanttohaveascleananatmosphereaspossiblepostbakingto
reducethepotentialforsporecontamination.Thefollowingsuggestionsmay
reducesuchcontamination:
1.
paper.Allsurfacesincontactwiththecakeshouldbeclean,dryandfree
fromflourdust.Preferablycoolingshouldnottakeplaceinthebakery
butinatemperature-controlledarea.
2.
Iftheproductistobecutordecoratedensurethatallutensilsusedare
cleananddryandwrapimmediatelyafterfurtherprocessing.
3.
Storetheproductinacoolplacebeforedispatch.
4.
Inlargerbakeries,cleanroomtechnologiescanbeeffectiveatlimiting
contaminationofproductsbeforeandduringwrapping.
Furtherreading
Cauvain,S.P.,Young,L.S.,2008.BakeryFoodManufacture&Quality:WaterControland
Effects,seconded.Wiley-Blackwell,Oxford,UK.
248
BakingProblemsSolved
5.10INTHELIGHTOFTHEPREVIOUSQUESTION,WHYDO
HEAVILYFRUITEDCAKESGOMOULDYMORESLOWLY?AND
ARETHEREANYSPECIALCONDITIONSWESHOULD
OBSERVEWHILEMAKINGCHRISTMASPUDDINGS?
Vinefruitsusedinheavilyfruitedproducts,suchasChristmascakesand
partlyasaresultofthehighnaturalsugarspresentinthefruitwhichlowers
theERHoftheproductandsoextendstheshelf-life.Alsotherearetracesof
naturalpreservativesinthefruitskinswhichwhilenotchangingthebatter
ERHwillimprovetheproductmould-freeshelf-lifebecausetheyprovidea
naturalinhibitorformouldgrowth.
Caremustbetaken,however,withproductslikethesethatthecakeor
puddingiscooledproperlybeforepackingtoensurethatthereisnolocalised
condensationonthesurfaceoftheproduct.Localisedcondensationprovides
areashighinmoistureand,whiletheoverallERHoftheproductmaybe
adequatetoensurethedesiredmould-freeshelf-life,ontheselocalisedareas,
therelativehumidityandmoisturecontentcanbehighenoughtoallow
mouldgrowthatafasterrate.
InChristmas-puddingproduction,thesteamingprocessactuallyadds
moisturetotheproductratherthanremovesitasisthecasewithconven-
tionalbaking.Anallowancemustbemadeforthisextramoistureinthefinal
life.Usually,ChristmaspuddingshaveanERHbelow80%andamoisture
thepuddingcanbecomesaturated(owingtotheevaporationofmoisture
fromtheproductintotheatmosphereinthepack).Ifthestoragetempera-
turesfluctuategrossly,thenmoisturecancondenseandfallontotheproduct
surfaceeitherbyspotcondensationfromthepackagingfilmoronthesides
ofthecontainer.Thelocalatmospherethenbecomesfavourabletomould
growth.Ifthepuddingbasinsarenotadequatelyfilledwiththepuddingmix-
ture,waterenterswhiletheyarestillboilingandremainstoamuchgreater
extentthanifthebasins/containershadbeenwellfilledandtightlysealed
beforeboiling.Whenthepuddingsareboiling,thewatermustnotbe
allowedtoceaseboilingbecauseifthetemperaturefalls,thepuddingsare
outsideofthepudding.Aftersteaming,thepuddingsshouldbecooledwith
thetopsurfacesexposedtopermitdryingoutwithoutriskofcondensation
andallowedtodryfor24

48hoursbeforepacking.
Furtherreading
Cauvain,S.P.,Young,L.S.,2008.BakeryFoodManufactureandQuality:WaterControland
Effects,seconded.Wiley-Blackwell,Oxford,UK.
Cakes,SpongesandMuffins
Chapter|5
249
OURDECORATEDCAKESANDTHEBOARDONWHICHTHEY
SIT.WHYSHOULDTHISHAPPEN?
Mouldsporesarealwayspresentintheatmosphereinabakery,particularly
wheretheremaybepoorhygieneoranexcessofflourdust.Mouldsinflour
dustareusuallydestroyedduringbaking.Theboarditselfmaynotbethe
sourceofcontaminationthoughthiscannotbediscounted.Thecakemayhave
pickedupthemouldsporespostbaking,forexample,fromasurfaceinthebak-
eryonwhichtherewasflourdust.Ifthesporesarepickedupandthecakeis
subsequentlyiced,theyaresealedbyplacingthecakeontheboard.Thehumid
conditionswhichwillbecreatedinthosecircumstancesprovidetheappropriate
conditionsforthemouldsporestogerminateanddevelopmouldcolonies.
ThisproblemonlyoccurswithcakesofhighERH(equilibriumrelative
boardandthecakesurfaces.Iftherelativehumidity(RH)ofthelocalised
trappedairisbelow75%,mouldgrowthwillnottakeplacedespitetheinitial
contamination.Thiscanbeachievedbypaintingthebaseofthecakewitha
concentratedsugarsolution(thusloweringtheRH)beforeputtingitonthe
baseboard

thebasisofthetraditionofpaintingonafruitpureeontothe
surfaceofcakes.Apractical,lowcostsolutionistoraiseafondanttoboiling
pointandpaintitoverthebaseofthecake.Thesyrupislargelyabsorbed
andalsohelpstoactasanadhesivetokeepthecakeinplaceontheboard.
andcrumbandthewholecakewillcomeintoequilibriumbutforalong
timethedesiredlocalisedreductioninERHnearthebaseismaintained
whichlimitsmouldgrowth.
Similarly,thetopsurfaceofasponge,whichmayhavebecomecontami-
natedfrommouldsporesintheatmosphereandwhichissubsequentlyiced,
coating.
Itisverydifficulttoeliminatecontaminationofthistype,butitcanbe
reducedbyplacingthecakesonacleandust-freesurfaceandcoveringthem
with,forexample,greaseproofpaperpriortopacking.Theboardsshouldbe
storedinadryplaceandprotectedfromcontaminationbydust.
Furtherreading
Cauvain,S.P.,Young,L.S.,2008.BakeryFoodManufactureandQuality:WaterControland
Effects,seconded.Wiley-Blackwell,Oxford,UK.
250
BakingProblemsSolved
5.12WEAREEXPERIENCINGMOULDGROWTHONTHE
SURFACEOFOURICEDCHRISTMASCAKES.THISISTHE
FIRSTTIMEWEHAVEHADTHISPROBLEMANDCANNOT
EXPLAINWHY.CANYOU?
Christmasandcelebrationcakesneedtobestoredwithcaretoavoidmould
growthontheirsurface.Thismouldgrowthiscausedbylocalisedareasof
highmoistureonthesurfaceoftheicedcake.Theselocalisedhighmoisture
areascanoftenformbecausethepresenceofundissolvedsugarcrystalsin
theicingwhichmakesithygroscopic.Ifcakesarestoredinacontainer
beforetheyarecompletelycool,condensationcanformonthesurfacesof
thecontainerorwrappingmaterialanddropontothecakeformingareasof
highmoisturewhicharegoodbreedinggroundsformould.Thistypeofcake
canbeaparticularproblembecausetheyarestoredforlongperiodsoftime.
Chapter|5
5.13WEAREEXPERIENCINGAMUSTY,OFF-ODOUR
DEVELOPINGINOURCAKES,EVENTHOUGHWESTORE
THEMINADEEPFREEZE.CANYOUADVISE?
Duetotheirhighsugarcontentcakesaresusceptibletopickingupboth
moistureandodoursfromthesurroundingatmosphere.Careshouldbetaken
tokeeptheareasandsurfacesofallcontainerscleanandfreefromother
materialswhichmightimpartodoursintotheatmosphere.Inthecaseofa
deepfreeze,itisimportanttoregularlyflushoutwithcleanwateranystag-
nantwaterwhichmightaccumulateinthedriptrayneartheevaporator.
Suchwaterprovidesabreedinggroundformouldsandbacteriawhichcan
produceodoursthatarereadilyabsorbedbythecakes.
BakingProblemsSolved
5.14WEREGULARLYMEASURETHEWATERACTIVITYOF
THEINDIVIDUALCOMPONENTSINOURCOMPOSITECAKE
PRODUCTSANDTRYTOADJUSTTHEMTOREDUCETHE
MIGRATION.EVENTHOUGHWEDOTHIS,WEARESTILL
HAVINGPROBLEMSKEEPINGTHECAKEMOISTDURING
SHELF-LIFE.CANYOUGIVEUSSOMEADVICEASTOWHAT
WEMAYBEDOINGWRONG?
Inadditiontobalancingthewaterac
tivitiesofthecakecomponents,there
areotherfactorswhichencouragethemigrationofwatertotakeinto
account.First,youshouldcheckyourpackaging.Moisturelostthroughthe
packwillcreateamoisturegradienti
nthepackwhichencouragesmoisture
migrationintheproduct.Cardboardpa
ckaginghasalowmoisturecontent
(andlowwateractivity)somoistureinthepackatmospherecanbe
absorbedbytheboardandsinceitisrelativelypermeable,caneasilypass
outtotheatmosphere.Aswellasthepermeabilityofthepackyoushould
checktheintegrityofthepacksealstoseethatnomoistureisescapingvia
thisroute.
Evenwhenthepackisnotlosingmoisturetothesurroundingatmo-
sphere,moisturewillmigratefromtheproductintothepackatmosphere.
Themassofwaterwhichcanbeheldinthepackatmosphereiscontrolled
bythesaturatedvapourpressureoftheair(
CauvainandYoung,2008
).This
islowatthetypicaltemperaturesusedtostorecakeproducts,butthegreater
thevolumeofairinthepackthegreaterwillbethemassofwaterrequired
toachievesaturation.Youmaywanttoconsiderwhetherthepacksizecan
tureimpermeablefilmbeforeplacingitinabox.
Youshouldlookcloselyattheformulationthatyouareusingforyour
creamfilling.Currently,youaremeasuringthewateractivityofthefilling,
butyoushouldcheckthatallofthesugarsthatyouareusinginthecream
tion,thenthecrystallinematerialwillincreasethelikelihoodofmoisture
migrationfromthecake.Thepresenceofcrystallinematerialisnotmea-
Wesuggestthatyoucarryoutamassbalancewithcompositeproducts;
thatis,youcalculatethemoisturesandwateractivitiesofthedifferentcompo-
nentstoseewherethepotentialisformoisturemigration,rememberingto
takeintoaccountthevolumeofairinthepack.Wealsofinditusefultodraw
adiagramshowingthelikelymovementofwaterinacompositecakesystem.
Furtherreading
Cauvain,S.P.,Young,L.S.,2008.BakeryFoodManufactureandQuality:WaterControland
Effects,seconded.Wiley-Blackwell,Oxford,UK.
Cakes,SpongesandMuffins
Chapter|5
253
5.15WHENWETAKEOURCUPCAKESFROMTHEOVEN,
WEFINDTHATTHEPAPERCASESTHEYWEREBAKEDINFALL
OFF.HOWDOWEAVOIDTHISPROBLEM?
Thetendencyforcakestoshrinkwhenbakedisthemostusualcauseofpaper
casesbecomingdetached.Theshrinkagegenerallyresultsfromtherecipehav-
ingtoohighaliquidlevelorsugarlevel,especiallyifthewatertosugarratio
isnotinbalance.Oncooling,thepressureofthesteamformedandmaintained
withinthecakewhileintheovenisreducedandthecakeshrinksunderthe
effectsnormalatmosphericpressure.Asthecasesarerigid,theyholdtheir
shape,andtheresultisthatthecakeshrinksawayfromthecase.
5.16OURSMALLCAKESOFTENSHRINKEXCESSIVELY
DURINGCOOLING.HOWCANWEAVOIDTHIS?
Allcakesshrinkalittleoncooling.However,excessiveshrinkingoncooling
occursbecausetheintactgascellsinthetexturecontract.Duringbaking,the
gascellsformingthefoaminthebatterexpandastheyarefilledwiththesteam
andgasproducedbytheraisingagents.Duetothehighquantityofsugarsin
thebatter,thegelatinisationtemperatureofthecakecellwallmaterialis
Chapter|5
TEXTURE.HOWCANWEIMPROVEIT?
Unitcakesarecharacterisedbytheiruniformandfinetexture(cellstructure).
Ifthetextureiscoarsetheadditionofasuitableemulsifiercanhelprectify
theproblem.Theemulsifierwillhelptoreducetheoverallsizeofthegas
bubblesincorporatedintothebatterandimprovetheirstabilityduringbak-
ing.Anumberofemulsifierpreparationsareavailable.Theycomeingel
andpowderedform,wesuggestthatyouconsultyouringredientssupplier.
Thepowderedformisusedintheformulationofdrycakemixes.Apro-
portionofsuchemulsifiersconsistsofacarrier,oftenskimmedmilkorwhey
powder.Ifthisisthecasethenyoushouldmakeallowancebyreducingthe
levelofmilksolidsintherecipe;otherwise,thecakemaybetoobrowndue
totheMaillardreaction(see
Section4.1.14
)andthepresenceoflactosein
themilkpowder.Youshouldhavenosuchproblemsifyouuseagelemulsi-
fier,butyouwillneedtoadjusttherecipewateradditiontocompensatefor
theinclusionofsomewaterinthegel.
10%offlourweight;youshouldreducethemilkpowderlevelbyabouthalfof
yournormallevelofadditioninyourrecip
etoavoidthepotentialfordarkening.
Inthecaseofagelemulsifier,around
2.5%flourweightshouldbesuitable.
Cakes,SpongesandMuffins
Chapter|5
257
5.19WHATARETHECAUSESOFTHESMALL,WHITE
CAKES?
Whitespecklesonthecrustofcakesaremostcommonlyduetosugarwhich
spots.Duringthebakingprocess,thereductionofmoisturecontentparticu-
larlyonthecrustcanresultinthesugarcomingoutofsolutionandforming
thespotsonthesurface.
Anychangesinthereciperesultinginareductionofmoisturecontentor
excessivesugar,therebyincreasingtheratioofsugartowater,maygiverise
tosugarspotformation.Forexample,thechangefrombutterorotherfat
containingaproportionofwatertoawhitefatcontainingnowatercanbe
enoughtoprecipitatetheproblem.Similarresultsmayoccurifanywater
containingingredientsarereplacedbyformscontainingnowater.
Otherfactorswhichmightcausesugarspottingoncakesinclude:

Increasedgranularityofsugarwhichmaypreventitdissolvingproperly
atthebatterstage.Asaprecaution,thesugarcanbedissolvedinthe
wateraddedtothebatchbeforemixing.Thisiseasilydonewithwhen
usingaflour-batter(see
Section5.1
Section5.2
)isemployed,sugarin
excessoftheweightoffatmaybedissolvedintheliquidportionbefore
essentialtoavoidthisproblem.

Bakingatalowerthannormaltemperatureorbakinginanovenwithtoo

Allowingthedepositedbattertostandfortoolongaperiodinthebakery
beforebakingmaycausesurfacedryingandsubsequentsugarspotting.If
usingatravellingoven,amuchshorterstandingtimeisrequiredbecause
ofthehotairpassingoverthecakesattheentrancetotheoven.Insuch
ovens,theproblemcanbeovercomebyapplying,byhandorautomati-
cally,anatomisedspayofwateroverthecakeswhiletheyareonthe
ovensoleandastheypassintotheoven.

Inroundcakeswherearingofbatter(asugarring)mayhaveoverflowed
thewrapperandhastendedtobecomeloose,aslightreductioninscaling
weightorincreasingtheheightofthepaperbandusedwouldhelptopre-
ventoverflowingandhencethelocalisedsugarspotting.
258
BakingProblemsSolved
Chapter|5
5.21WHENWEADDFRESHFRUITSSUCHAS
FINDTHATTHEYFAILTOKEEPTHEIRCOLOURDURING
BAKINGANDOFTENDISCOLOURTHEBATTERADJACENT
TOTHEFRUIT.CANYOUOFFERANEXPLANATIONANDA
SOLUTIONTOTHEPROBLEM?
Thisproblemoccursbecausethenaturalcolouringagentsintheblackcur-
rantsandmanyotherfruits(see
Section5.23
)arepHsensitive.Thismeans
thattheywillchangecolourasthepHchanges.Forexample,anthocyanin,a
majorcolouringcomponentofblackcurrantsandotherredfruits,willchange
overcometheproblem,wesuggestthatyoumakethebatterslightlymore
acidbyaddingupto0.3%tartaricacidbasedonflourweight.Thisshould
maintainthebasiccolourofthefruitwithoutadverselyaffectingothercake
qualities.
Theleakingofthecolourintothesurroundingbattercomesfromdamage
tothefruitskinsduringmixinganddepositing.Thisisdifficulttoavoidbut
youshouldkeepthehandlingoffruitinthebattertoaminimum.Youmaytry
theadditionoffrozenfruitsasthismayhelptoavoidrupturingthefruitskin.
Blueberrieshaveatougherskinandsoarelesssensitivetomechanicalhan-
dlingthanblackcurrants.However,theyarejustassensitivetopHchanges.
260
BakingProblemsSolved
5.22WEAREBAKINGFRUITCAKESUSINGSULTANASAND
FINDTHATWHILETHECENTREOFTHECRUMBISANICE
GOLDENYELLOWAROUNDTHREESIDESOFTHECUTFACE
OFTHECAKE(THEBOTTOMANDTHETWOSIDES)THE
COLOURISMUCHBROWNERANDDARKERINCOLOUR.
CANYOUHELPUSIDENTIFYTHECAUSEOFTHISPROBLEM?
ThistypeofdiscolourationisusuallyassociatedwiththeMaillard-typereac-
tionswhichtakeplaceinbaking(see
Section4.1.14
).Thesearetheones
whichgivesthebrowncoloursofthecrust.Theyarecomplicatedreactions
influencedbyanumberofdifferentfactors(
Arnoldi,2004
)whichinvolve
sugarsandproteins.
Youshouldlookfirstatyourbakingconditions.Lowbakingtempera-
turesandlongbakingtimestendtoincreasetheriskofcaramelisationof
sugars,especiallyinlargecakeunits.Youmightalsowanttolookatthedis-
tributionofheatintheovenastheproblemisexacerbatedbyhavingtoo
muchbottomheat.
Somesourcesofsugarsaremorelikelytocausebrowningofthistypein
cakes.Yourproblemwillbeexacerbatedifyouhavesourcesofreducing
sugarslikegoldensyrup,glucosesyrups,invertsyruporhoney.Theseare
commonlyusedingredientsintendedtocontributeflavourandinsomecases
Asaruleofthumb,youshouldlimitthelevelofadditionofsuchsugars
collectivelytonomorethan10%ofthetotalweightofsugarsintherecipe.
Youcanencountersimilarproblemsifyouareaddingglycerolorsorbitol
toextendproductshelf-life.Forrecipebalancepurposes,youshouldcon-
siderthesetobesugarsandincludetheminthe10%limitation.
Onelessthanobvioussourceofreducingsugarsisthefruitthatyouare
addingthoughifthisisaproblemthenyouwilloftenseedarkerstainsin
thecrumbaroundthepiecesoffruit.Youcouldwashanddrainthefruitand
seeifthismakesanydifferencetotheproblem.Becarefultocheckthatthe
increasedmoisturecontentofthefruitdoesnotcauseyouproblemsby
raisingtheproductwateractivityandshorteningthemould-freeshelf-lifeof
theproduct.Thiswillbeparticularlyimportantifyouarecuttingtheslab
intosmallerpiecesandexposingthecutsurfacetoviewasthisincreasesthe
risksofmouldcontamination.
Finally,checkthatyouarenotusingtoomuchsodiumbicarbonateinthe
recipeasanyresiduewillraisethecakepHandincreasetheextentofthe
Maillardreactions.
Reference
Arnoldi,A.,2004.FactorsaffectingtheMaillardreaction.In:Steele,R.(Ed.),Understanding
andMeasuringtheShelf-lifeofFood.WoodheadPublishingLtd,Cambridge,UK.
Cakes,SpongesandMuffins
Chapter|5
261
5.23WEAREUSINGNATURALCOLOURSINOURSLAB
WITHINABATCH.CANYOUSUGGESTANYREASONS
FORTHISPROBLEM?
Beingderivedfromnaturalmaterialscolourscanbesubjecttovariationsin
shadeandintensityofthecolour.Thisisusuallywellcontrolledbythesup-
plier.AllcoloursareaffectedbythepHofthemediuminwhichtheyare
used.NaturalcoloursareespeciallysensitivetovariationsinbatterpH,and
thiscanleadtoproblemswhenmakingadditionsoffreshfruits(see
Section
5.21
).Ifthiswasthesourceofyourproblem,wewouldonlyexpectyouto
seevariationsonabatchtobatchbasisasareflectionofthesmallvariations
inbatterpHwhichcanoccurinanymanufacturingenvironment.
Whenusedinbakedproducts,naturalcoloursarelikelytosufferfrom
someinstabilityduringtheirstorage.Commonly,thiswillbeseenasaloss
ofintensityofthecolour,butusually,theoverallstoragetimeistooshort
forcakesforanysignificantvariationstocomefromthissource.
withinabatchisunusual.Somenaturalcoloursareknowntolosecolour
intensityduringbakingsoonepossibilityisthatthevariationsincolourthat
youseemayreflectthedegreeofbakewhichaparticularcakehasreceived.
Asyouwillappreciate,thereareinevitablysomevariationsinthedegreeof
bakewithinanoven.
Naturalcoloursareparticularlysusceptibletotheeffectsofexposureto
light.Inparticular,theytendtolosecolourintensitywithincreasingexpo-
sure.Yellowcoloursappeartobemorelikelyaffectedthanreds.Yourcakes
aremorelikelytobeaffectedbylightiftheyarewrappedinclearfilm.This
isoftenthecaseincakemanufacturebasedonslabcakesasitallowsthe
consumertoseetheproductanditsqualities.
Wesuggestthatyoulookcloselyathowyourcakesampleshavebeen
storedwithrespecttoanylightsources,whethernaturalorartificial.This
shouldincludeallofthetimesforwhichthecutsurfacesofthecakesare
exposedtolightsources,includingstandingtimesinthebakerywhilethe
compositeproductisbeingassembledbeforewrapping.
262
BakingProblemsSolved
Chapter|5
5.25OURSULTANACAKESARECOLLAPSING.WHATCAN
WEDOTOREMEDYTHISPROBLEM?
Manyofthefaults,whichoccurincakemaking,arearesultoftheingredi-
entsintherecipenotbeingbalancedforthetype,sizeandshapebeing
made.Thisbalancingofingredientratiosisimportanttoensurethecorrect
aerationandstructureforthebakedproduct(seechapter:KeyRelationships
BetweenIngredients,RecipesandBakedProductQualities).
Youdidnotspecifywhetherthecollapseoccursduringbakingorafter
baking.Thisisanimportantclueastowhytheproblemisoccurring.
Inthecaseofthesunkentopthefollowingingredienteffectsare
relevant:

Thesugarlevelmaybetoohigh.Thelategelatinisationofthestarch
meansthatthetransitionfromfoamtospongedoesnotoccurbeforethe
endofbaking(see
Section4.2.1
).

Thefatlevelmaybetoohigh.

Thebakingpowderlevelmaybetoohigh.
Youmayneedtorebalanceyourecipetoeliminatethisproblem.
Otherreasonswhyacakemigh
tsinkinitsmiddleinclude
removingthecakefromtheovenbefore
itisthoroughlybaked.Thecentre
ofacakeisthelastportiontobakesothatiftheproductisremovedfrom
itssourceofheatwhenitisstillfluidthecrustwillbeunsupportedand
thecakesinks.
Ifthecakesareknockedormovedaboutwhilsttheyarebakingand
gaseswhichcancausethecakestosinkinthecentre;thiswouldoftenbe
accompaniedbyalossofvolume.
Cakes,SpongesandMuffins
Chapter|5
265
5.27WEAREENCOUNTERINGANINTERMITTENTFAULT
WITHOURROUNDHIGH-RATIOCAKESINTHATASHINY
RINGWITHPITTINGISSEENONTHECAKESURFACE.WHAT
FACTORSARELIKELYTOGIVERISETOTHISFAULT?
Thisfaultiscausedbythebatterviscositybeingtoolowduringtheearly
stagesofbaking.Astheproductisheatedtheviscosityofthebatterhelpsto
trapthegasesproducedbytheraisingagents.Ifthebatteristoofluidthen
5.28OURFRUITEDCAKESAREFINETOEATSOONAFTER
PRODUCTIONBUTTENDTOBECOMEDRIEREATINGAFTER
AFEWDAYS;WHYISTHIS?
Fruitedcakesareamulti-componentproductcomprisingtwophases;thecake
crumbandthedriedfruit.Eventhoughthetwocomponentsareinintimatecon-
tactfrommixingthroughtobakedproduct,equilibrationofmoisturedoesnot
necessarilyoccur.Inmanycasesafterbaking,thereisasignificantdifferencein
cakecrumbandfruitparticlemoisturecontentwiththedriedfruitcontinuingto
absorbmoisturefromthecakecrumb.Experimentaldata(
CauvainandYoung,
2008
)hasshownthatuptofourdaysmayberequiredforequilibriumtobe
achieved(see
Fig.5.1
).Thislackofmoistureequilibriumismostlikelytobe
thereasonforthedryeatingcakecrumbthatyouareobserving.
Onewaytoovercomeyourproblemistoraisethemoisturecontentof
yourfruitbywashinganddrainingitbeforeuse.However,notethatthiswill
raisetheoverallmoisturecontentofthecakeandmaydecreaseitsmould-
freeshelf-life.
Thereareseveralwaysofpreventingcrumblingwithfruitcakes:

Useflourofmediumstrength(10

11%protein)insteadofhigh-ratio
cakeflour.

Theproportionoffatusedshouldbelessthantheeggcontentbyapprox-
imately10%(basedonflouras100%).
FIGURE5.1
Effectoffruitoncakemoistureduringstorage.
Cakes,SpongesandMuffins
Chapter|5
267

Wheretheratioofsugartoliquidishigh,thecakethecrumbtendstobe
morefragile.Forafruitcakethisratioshouldbelowerthan115%flour
weight.

Whentheproportionofegginthetotalliquidislowthecakestructureis
weakandhasatendencytocrumbleoncutting.Eggshouldmakeup
about50%ofthetotalliquidstopreventthis.

Emulsifieradditionsshouldbekepttoaminimum.

Avoidhighlevelsofraisingagentsasthesecanincreasecrumbfragility.

Washthefruitanddrywellbeforeuse.

Mixingmustbecontrolledtoensureconstantbatteraerationandemulsi-
fication.Under-mixingandover-aerationofbatterscancauseacrumbly
endproduct.

Batterdepositingandbakingshouldnotbedelayedaftermixing.
Furtherreading
Cauvain,S.P.,Young,L.S.,2008.BakeryFoodManufactureandQuality:WaterControland
Effects,seconded.Wiley-Blackwell,Oxford,UK.
268
BakingProblemsSolved
5.29WEHAVESEENTHATOURCAKEQUALITYVARIES
WHENWECHANGEFROMONETYPEOFOVENTO
ANOTHER,EVENWHENTHEYREGISTERTHESAME
TEMPERATURE.WHYISTHIS?
Ovens,eventhoseofthesamemakeandmodelvaryintheirabilityto
Chapter|5
theproductcrust.Asmostproductsarebakedtoaparticularcolourand
shape,thetemptationinthesecircumstancesistolowertheoventemperature
forthenextbake.Youshouldavoidthisifpossible.Ifyouareabouttouse
anovenwhichhasbeenstandingemptybutheatingforaperiodoftimeand
yoususpecttheremaybeproblemswithflashheat,wesuggestthatyouinject
aburstofsteamintothechamberandreleaseitbeforeloadingtheovenwith
product.Theevaporationofthewaterwillremovesomeoftheexcessheat
andreadilyescapeswhenyouopentheovendoorordamper.Ifyouusethe
latter,remembertocloseitagainwhenyouloadtheproductintotheoven;
otherwise,youcouldendupdryingtheproductoutunnecessarily.
Variationsinovenhumiditycanalsoleadtovariabilityforsomepro-
ducts.Forexample,Swissrollsbenefitfromhumidityintheovenasthe
watervapourkeepsthecrustmoistandsoaidstherollingprocess
postbaking.
Althoughyourproblemisassociatedwithcakes,youmightliketonote
thatthesameruleswillapplytoalmostallbakedproducts.
BakingProblemsSolved
5.30HOWIMPORTANTISTHETEMPERATUREOFCAKESAT
THEPOINTOFWRAPPING?
Cakescanbewrappedateitherhightemperaturesorcompletelycooled.In
eithercase,theimportantpointistoensurethatnolocalisedcondensation
occursonthesurfaceoftheproductwhichmightresultinmouldgrowthduring
storage.TheERHoftheproductshouldremainatthelevelrequiredtoachieve
thedesiredmould-freeshelf-life(see
Section5.9
).
Ifacakerequiresnofilling,coatingorotherfinishingafterbakingthere
isnoreasonwhyitshouldnotbewrappeddirectfromtheovenattempera-
turesaround88

93

C(190

200

F).Obviously,theremaybesomedifficul-
tiesinvolvedinwrappingatthesehightemperatures,suchasdamagetoa
fragileproductandcontrolofcondensationastheproductcools.Provided
thewrappingmaterialisinreasonablyclosecontactwiththeproduct,con-
densationwhichdoesoccursoondisappearsevenwhenamoistureimperme-
ablefilmisused.
Materialsforwrappingathightemperaturesshouldbechosenwithcare.
ofcellulosefilmdonotappearadverselyaffectedbyhotwrapping.
Ifproductsaretobecooledthenwrapped,caremustbetakenduringthe
coolingprocess.Rapidcoolingcanbeachievedwithsuitablyhighairveloci-
ties.However,ifdryingoutoftheproductistobeprevented,therelative
humidityinthecoolermustbecarefullycontrolled.Therelativehumidity
canbecontrolledonlyiftheairtemperatureiscloselyregulatedasrelative
humiditychangesrapidlywithasmallchangeinairtemperatureatagiven
moisturevapourcontent.
Ifrefrigerationisusedbothtemperatureandrelativehumiditycanbe
controlledsatisfactorilywithanairtemperatureof,say,16

C(60

F)and
about80

85%relativehumidity.Topreventtheproductdryingout,therel-
ativehumidityshouldbeclosetotheequilibriumhumidityoftheproduct
(typically80

85%forcakes)sothatmoistureisnotencouragedtomove
fromtheproduct.Thehighrelativehumidityinarefrigeratedsystemmeans
thatlargecoolingplatesarerequiredtopreventcondensationofmoisture
ontothecoolingcoils.
Withoutrefrigeration,relativehumiditycanbecontrolledusingwater
spraytypehumidifiers.Inthiscase,closecontrolismoredifficultespecially
iftheairtemperature(around21

C,70

F)issubjecttofluctuations.
Cakes,SpongesandMuffins
Chapter|5
271
Themoisturelossfromflourconfectioneryproductsduringcoolingmay
ties.Ifcontrolledcoolingconditionsareused,itispossiblethatanincrease
inthemoisturecontentoftheproductcouldoccurwitharesultingreduction
intheshelf-life.Itisadvisabletomakecarefulchecksonmoisturecontent
decreasetheERHoftheproduct.
Undercontrolledcoolingconditions,itisimportantthatanyairblown
overtheproductiscleanandthoroughfilteringofairdrawnfromoutsideis
desirable.
Coolingtimesaredependentonthesizeandthermalconductivityofthe
product.Itispointlessusinghighairvelocitieswithlargeproducts,ascool-
ingtimeiscontrolledmainlybythetimetakenforheattobeconducted
fromthecentreoftheproducttotheoutside.
Furtherreading
Cauvain,S.P.,Young,L.S.,2008.BakeryFoodManufactureandQuality:WaterControland
Effects,seconded.Wiley-Blackwell,Oxford,UK.
272
BakingProblemsSolved
5.31WHATPRECAUTIONSSHOULDWETAKEWHEN
FREEZINGCAKEANDSPONGEPRODUCTS?
Thegreatestbenefitstobegainedfromfreezingcakesandspongesarethe
delayofthestalingprocessandavoidanceofproblemswithmould-free
shelf-life.Providedtheproductsareadequatelyprotectedagainstmoisture
loss,youwillpreservetheirfreshnessandlimitmoisturemigrationincom-
positecakeproducts.
Beforefreezing,theproductsshouldbecooledtoambienttemperature
(typically20
C,70
F)tomaintaintheefficiencyofthefreezing
process.Themostefficientandeconomicalfrozenstoragetemperature
F).However,cryogenicfreezingsystemsusingliquidnitrogen
orcarbondioxidehaveledtotheuseofmuchlowertemperatures,
F)forliquidnitrogenand
F)forliquidcarbondioxide.
Incommonblastfreezers,fansoperatinginsuchequipmentaidheattransfer
andairtemperatureswilltypicallybeintheorderof
30to
C.The
productsshouldspendaslittletimeinthefreezeraspossibletoreducemois-
turelosses,butyoushouldmakesurethatcoreproducttemperaturesreachat
least
Cbeforetransferringthemtofrozenstorage.Thehighlevelsof
sugarsincakesandspongessignificantlydepresstheirfreezingpointand
makesthensusceptibletotheeffectsoffluctuationsinfrozenstorage
temperature.
Itisadvisabletouseaspeciallyproducedmoisture-prooffilmwhichhas
increasedflexibilityandisresistanttocracking.Wrappingtheproducts
beforefreezingwillhelpreduceevaporativelossesbutdoesincreasethe
lengthoftimetakenfortheproducttobecomefrozen.
Storagetimesforfrozenproductsvarybutcanbemanyweeksat
F).Rememberthatifproductsarestackedinfrozenstorage,thenthe
temperatureoftheproductmayvaryaccordingtoitspositioninthestack
andinsomecasesmaybeunacceptablyhighwithsubsequentdefrosting.
Thethawingtimeforfrozencakesandspongesdependsontheunitsize
andthawingconditionsavailable.A285g(10oz)sizedplainslabcakecan
takeupto6hoursstandingat21
C(70
F)beforetheinternaltemperature
reaches21
Cbutsuchacakewouldbeeatablewithin4hours.Ifthesame
cakewasthawedat38
C(100
F)aninternaltemperatureof21
Cwould
bereachedwithin1.75hours.Dryeatingproductsmayoccurifthethawing
rateistooslowresultinginexcessivemoisturelosses.
Condensationcanoccurduringthawinganddependslargelyonthethaw-
ingtemperature,whichcontrolsthetimeduringwhichthesurfacetempera-
tureoftheproductremainsbelowthedewpointoftheatmosphereinthe
packaging.Thehigherthethawingtemperature,themorequicklyisthecon-
densationremovedandthelesslikelyitistoaffecttheproduct.
Cakes,SpongesandMuffins
Chapter|5
5.32WHATHAPPENSTOTHEBATTERWHENCAKESENTER
THEOVEN,ANDHOWCANYOUTELLWHENACAKEIS
BAKED?
Convertingafluidbattertothedesiredeatingcharacteristicsintheendprod-
spongestructure(interconnectedcells)inthebakedproduct.Bakingisa
processofheatgainandmoistureloss.
Evenbeforethecakeenterstheoven,theconditionoftheovenisimpor-
tant.Anybuildupofflashheatshouldbedissipatedsothatthecake
receivesanevenbake.Oncethecakeisintheoven,theheatstartstomelt
thefats.Thisfirstoccursontheoutsideofthecakeandgraduallyextendsto
theinnerportions.Atthesametimetheaircellsbegintoexpandandifrais-
ingagentsarepresentcarbondioxideisreleasedtoinflatethecells.This
beginsslowlyatfirstfromtheoutsideandgraduallyextendstotheinterior
ofthebatter.Thetemperatureofthecakecontinuestoriseandsomeofthe
starchgranulesaregelatinisedwhilethecakeisstillinamoltenstate.The
theoutsideofthecakecolourstogivetherequiredsizeandappearance.The
continuedexpansionofthecellsalongwiththegelatinisationofthestarch
causesthefoamcellsofthebattertobecomerupturedtoformtheintercon-
nectedcellsofthefinalstructure.
Ifthecakesaresmallandtheovenishot,askinformsquicklyonthetop
andrapidlycoloursasthemoistureinthevicinityofthesurfaceisconverted
tosteamleavingthesugaryportionofthebattertoreachatemperaturewhere
theMaillardreactionsoccur(see
Section4.1.14
)andthesugarscaramelise.
Althoughthisskinformsquickly,itwillnothavesufficientstrengthtoprevent
theinteriorofcakeexpanding(especiallywhere,thereisahighproportionof
bakingpowder).Thepressureeventuallyexceedsthestrengthofthetop.The
topistheweakestportionofthecakeasthesidesandbottomareoftensup-
portedbythetinorhoop.Thebatterforcesitswaythroughtheformingcrust
andaroundedorboldheadisformed.Thisissmallatfirstbutgrowsasbak-
ingcontinues.
Inlargercakes,thetopskintakeslongertoform,asinthesecases,the
oveniscooler(toallowforamoreevenbakeandtopreventtheoutside
beingburntbeforetheinsideisbaked).Alsothehumidityintheovenis
higher(e.g.,whentheovenisfullofproducts),andaslargercakesusually
containahigherproportionofeggsthanmilk,theygiveuptheirmoistureat
dealofthewaterthatwouldotherwisehavebeendrivenoffassteam.Ifthe
recipeiscorrectlybalanced,theburstingthroughthecentretopisless
pronounced.
274
BakingProblemsSolved
Chapter|5
5.33WHATARETHEADVANTAGESOFHAVINGTHEOVEN
FILLEDWHENBAKINGSLABOROTHERCAKES?
Theadvantagesofhavinganovenfilledwithproductcomefromthehumid-
ityandheattransfer.Oncecakesareplacedintheoventheirtemperature
risesandeventuallythemoistureintheproductreachesboilingpointand
steamisgivenoff.Iftheovenisfullofproduct,thenthevolumeofsteam
willbefairlylargeforagivenvolumeofovencapacity.Thehumidityinthe
ovenwillbehighandwillactonthesurfaceofthecakekeepingitmoist.
Aseachcakeisincloseproximitytoitsneighbour,thesidecrustswillbe
keptthinandpaleincolour.Thehardeningordryingofthefinalcrustson
thetopandsideswillbedelayedenablingthecaketoreachfullgrowth
insideofthecakewillburstthroughtheprematurelyformedcrustandform
abreakorcrackacrosstheslab.Insomecasesthisbreakmaybedesired,
e.g.,Muffins(see
Sections5.47and5.48
).Theatmosphereintheovenis
fully.
Forslabcakes,abreakonthesurfaceisnotdesirableandsoafulloven
isanaimwiththeovendoorremainingclosedforthewholebakingperiod.
Wherethisisnotpossible,ahumidatmosphereshouldbecreatedinthe
ovenbyplacingtinsofwaterintheovenwiththeproduct.
276
BakingProblemsSolved
5.34WHYDOWEADDEXTRAACIDTOMAKEWHITECAKE
BATTERS?
tralisedbytheacidcomponentthentheexcessbicarbonatewillincreasethe
degreeofdegreeofbrowningofthesugarsduringbaking.Thisisbecause
Maillardbrowning(see
Section4.1.14
)isencouragedathigherpHs.This
typeofbrowningoccurswithalltypesofcakesbutbecausethecrumbof
manycakesistintedyelloweitherwitheggyolksoreggcolourtheslight
degreeofdiscolourationlargelypassesunnoticed.Inthecaseofawhite
cakewherenoeggyolkispresent,theslightestdiscolourationwouldbe
noticed.Topreventthistherefore,additionalacid

suchascreampowder
orcreamoftartar

isaddedtomakesurethatallthebicarbonateofsodais
neutralised.
Cakes,SpongesandMuffins
Chapter|5
277
5.35WEHAVEBEENMAKINGARANGEOFDIFFERENT
VARYINGQUALITYRESULTSINTERMSOFTHEIRSHAPEAND
APPEARANCEDESPITEHAVINGADJUSTEDTHEBAKING
CONDITIONS.DOYOUHAVEANYADVICE?
Traditionally,bakerswouldchangetwoaspectsoftheirproductioniftheyused
thesamebatterfordifferentsizeproducts.Oneofthesewouldbetochangethe
bakingconditionswhichiswhatyouhavedone.Heatcanonlyreachthecentre
ofthebatterforeachunitbybeingabsorbedatthesurfaceandthentransferred
tothecentre(see
Section5.32
).Incakeshapeswhichhaveasmallsurfacearea
(SA)relativetotheirdepthorthickness,theovenbakingconditionsareadjusted
toallowtherateofheatpenetrationtobecompatiblewiththevariouschanges
whichoccurincakebaking.
Asthebatterisheatedintheoven,carbondioxidegasfromthebaking
powderpresentintheformulationisreleased.Itiscommonpracticetoadjust
thelevelofbakingpowderaccordingtothecaketype.Thebakersruleof
thumbisthatthelevelofbakingpowderishigherforsmallcakeunitsand
lowerforlargecakeunits.Toomuchortoolittlebakingpowderforagiven
productrecipecanhaveanadverseimpactoncakeshape(see
Section5.39
).
Asamatterofinterestwetookthreerecipesforthreecommoncakepro-
ducts

slab,loafshapeandcupcake

andcalculatedtheratioofsurfacearea
(SA)tothethickness(T)ofthebatterdepositinthepan.Usingthisratio,we
thenplotteditagainstthetraditionallevelofbakingpowderintherecipewith
theresultsshownin
Fig.5.2
.Thestraightlineshouldonlybeseenasaguideto
oneprinciplethatshouldbeemployedinadjustingbakingpowderlevelsin
cakerecipesratherbeingindicativeofanabsoluterelationship.
FIGURE5.2
278
BakingProblemsSolved
5.36WEWOULDLIKETOCHANGETHEPHYSICAL
DIMENSIONSOFSOMEOURCAKEPRODUCTSTOMAKE
DIFFERENTSIZESANDSHAPESDOYOUHAVEANYADVICE
THATYOUCANGIVEUSASTOHOWTOADJUSTTHE
BATTERDEPOSITWEIGHTSFORTHEDIFFERENTPANSIZES?
Thereisnosimpleformulawhichallo
wsyoutocalculatebatterdeposit
weightsfordifferentdimensionsofpan.Atfirstsightthismayseem
strangebutinfactthereisaperfec
tlyreasonableexplanationanditis
relatedtothetransferofheatintoth
eproductduringbaking.Intheoven
heatisabsorbedbythesurfaceofthebatterbeforebeingconductedfrom
thesurfacetothecentreoftheproduct.Therateatwhichtheheatreaches
thecentredependsinpartonthedis
tancefromthebattersurfacetothe
centre;ingeneraltermsthegreaterth
edistancefromsurfacetocentrethe
longeritwilltakefortheheattotravelthedistance(foragivensetofbak-
ingconditions).However,ascakebatte
rshavealowviscositybycompari-
sonwithmostotherunbakedproducts(e.g.,doughandpaste),thereis
stagesofbaking(
CauvainandYoung,2006
).Thepotentialforsuchcon-
vectioncurrentsisgreatestinproductswhichthesurfaceareaissmallrela-
tivetothedepth(thickness)ofthedeposit.
Forcakes,thepracticalimplicationofthedifferentratesofheattransfer
arethatthekeychangesinconversionfrombattertocake,suchasthegen-
erationofcarbondioxidefromthebakingpowderandthetransitionsfrom
bakedproduct.Changetheheattransferrateandyoucanendup
compromisingkeyproductc
haracteristics.Bakershavelearnttocompen-
satefortheseeffectsbyadjustingbakingconditionswhenchangingproduct
dimensions.
Thefollowingtableusingthesamebatterformulation(exceptforlevelof
bakingpowder

See
Section5.35
)illustratestheprinciplesthatwehave
describedaboveandmayhelpyouinmakingyourdecisiononscaling
weights.
Cakes,SpongesandMuffins
Chapter|5
279
PanshapeLength/
(cm)
Breadth
(cm)
Depth
(cm)
Pan
volume
(cm
3
)
Deposit
weight(g)
Baking
temperature
(

C)
Rectangular158.581020300185
Rectangular45752.584373500205
Rectangular4575516,8758500190
Square151551125370190
Round133398250190
Round202.5785320200
Reference
Cauvain,S.P.,Young,L.S.,2006.BakedProducts:Science,TechnologyandPractice.Blackwell
Publishing,Oxford,UK.
280
BakingProblemsSolved
5.37WEHAVERECENTLYCHANGEDTHEACIDTHATWE
USEFOROURBAKINGPOWDERMIXANDHAVEADJUSTED
THENEUTRALISINGVALUEACCORDINGLY.SUBSEQUENTLY,
WEHAVEBEENHAVINGSOMEPROBLEMSACHIEVINGTHE
VOLUMEANDSHAPETHATWEWANTWITHOURSMALL
CAKES.CANYOUEXPLAINWHYWEAREHAVINGTHESE
PROBLEMS?
The
neutralisingvalue
referstheproportionofagivenacidwhichisrequired
thisproportionvariesaccordingtothechemistryoftheacid(see
Section
2.6.8
).Inadditiontohavingadifferentneutralisingvalue,eachacidhasits
ownRORwhichindicatestherateatwhichitwillreactwithsodiumbicar-
bonatetoproducecarbondioxidegas.Inaddition,someofthebakingacids
andthesodiumbicarbonateareavailableindifferentgrades

commonly
duetodifferentdegreesofparticlesize

andthistooaffectstheROR
becausetheacidandalkaligointosolutionatdifferentrates.
TheRORofabakingpowdermixtureandthetimingofthereleaseof
carbondioxideareimportantcontributorstocakevolumeandshape.Ifthe
RORistoorapidthenmuchofthecarbondioxidewillbereleasedduring
mixing,andtheearlystagesofthebakingprocesswhichtendstoleadtothe
cakeslackingvolumeandoftenhavingashapewhichispeakedratherthan
rounded.AsimilarproblemcanoccuriftheRORoftheacidistooslowand
themajorityofthecarbondioxideisreleasedwhenthestructureofthecake
AvisualsummaryoftheeffectoftheRORofthebakingpowderoncake
shapeisgivenin
Fig.5.3
.Tofindoutwhereyouareontheshapespectrum
whichmatchestheshapeofyourcurrentcakeproducts,andthiswilltellyou
whetheryourRORhasincreasedordecreased.
Fig.5.3
)
increased.Tomovethecakeshapeinaparticulardirection,youmayneedto
chooseanalternativebakingacid.TheRORcannormallybeobtainedfrom
yourbakingpowdersupplier.
SLOWFAST
FIGURE5.3
Effectofrateofbakingpowderreactiononcakeshape.
Cakes,SpongesandMuffins
Chapter|5
281
5.38WHATARETHEFACTORSWHICHCONTROLTHE
SHAPEANDAPPEARANCEOFTHETOPOFACAKE?
Themaininfluencesontheshapeandappearanceofthetopsurfaceofcakes
fallintothreecategories;thebalanceofliquidstosugarsintherecipe,the
ferduringbaking.
Theconcentrationofthesucrosesolutionincakerecipeshasasignificant
effectoncakesshape(andotherstructuralfeatures).Asthelevelofsugarin
acakerecipeincreases,thetemperatureatwhichthewheatstarchgelatinises
israised,andthebatterstaysfluidforlongerintheoven.Atlowrecipe
sugarlevels,cakestendtohavearoundedandslightlypeakedprofilebutas
thelevelincreases,theshapebecomesprogressivelyflatter(
Fig.5.4
).
Continuedincreasesinrecipesugarlevelleadtocollapseofthestructureso
thatadipappearsinthesurfaceofthecake.
Thevolume,structureandappearanceofcakesdependoncreatingagas
bubblestructureinthebatterwhichwillbeexpandedbythereleaseofcar-
bondioxidefromthebakingpowderreaction.Achievingtherightbalanceof
mechanicalandchemicalaerationisimportantforcontrollingshape.The
examplesshownin
Fig.5.5
arebasedoncakerecipeswhichhaveallbeen
mixedtothesamebatterdensitybutwithdifferentlevelsofbakingpowder
inthestartingrecipe.Thismeansthatthebatterwiththelowestbakingpow-
derlevelhasthehighestproportionofairincorporatedintothebatterwhile
thatwiththehighestlevelofbakingpowderhasthelowestlevelofairincor-
poration.Thisfollowsbecausethereissomereactionofthebakingpowder
INCREASING LEVEL OF ADDITION
FIGURE5.4
Theeffectofincreasingsugarleveloncakeshape.
INCREASING LEVEL OF ADDITION
FIGURE5.5
Effectofbakingpowderleveloncakeshape.
282
BakingProblemsSolved
componentsintheinitialmixingstages,andsomeofthecarbondioxidegas
producedatthistimeremainstrappedinthebatter.Theillustrationshows
thatasthelevelofbakingpowderincreases(forthesamefinalbatterden-
sity)thatthecakeshapebecomeslessdomedandeventuallywithhighlevel
ofbakingpowderadipappearsinthesurface.
Theimpactofhighlevelsofbakingpowderispronouncedbecausealot
ofthecarbondioxidegasisreleasedintheovenatatimewhenthewheat
natureofthemechanicaltochemicalaerationbalancecanalsobeseenwhen
theRORofthebakingpowderintherecipeischanged.Aslow(late)release
ofthecarbondioxidecommonlyyieldsaproductwithapeakedshape,and
asthereactionrateincreases,thecakeshapegraduallyflattens(
Fig.5.3
).
However,fastreactingbakingpowdersalsogivepeakedshapeproducts.
Thisisbecausemostofthecarbondioxideescapeswhilethebatterisvery
fluidandnoneisleftforexpansionatthestarchswellingstage.
Rapidheattransferratesintheoven(hightemperature)tendtocausethe
cakeshapetobecomemorepeaked,asdoesahightopheatwhenbakingin
adeckoven.
Cakes,SpongesandMuffins
Chapter|5
283
5.39CURRENTLY,WEADDALCOHOL,INTHEFORMOF
SPIRITSORLIQUEURS,TOOURCELEBRATIONCAKESAFTER
THEYHAVEBEENBAKEDANDCOOLED.WELEAVETHEM
FORAFEWDAYSAFTERTREATINGTHEM,BUTTHISIS
TAKINGUPALOTOFSPACE.WHATADVANTAGES/
DISADVANTAGESWOULDTHEREBEIFWEADDTHE
ALCOHOLTOTHEBATTERBEFOREBAKING?
Theboilingpointofalcoholisaround78
C,soyoumightexpectamajor
proportionofanyaddedbeforebakingwillbeevaporatedduringthebaking
process.Therearefewestimatesastohowmuchofthealcoholaddedtoa
cakebatterislostduringbakingandtheyvaryfrom50%to90%.Thereisa
suggestionthatthelossesarelowerwithheavilyfruitedcakesofthetype
thatyouaremakingandgreaterwithlightlyfruitedorplaincakes.Itappears
moisturemigrationfromthecakecrumbtothefruitsothattheformerstays
moremoisteating.
5.40WHYDOSOMETRADITIONALSPONGECAKEMAKING
SODIUMBICARBONATEANDTHEUSEOFHOTWATER?
WOULDTHISAPPROACHHAVEANYPRACTICAL
APPLICATIONSTODAY?
meansofcontrollingthereactionofthebakingpowdercomponentsandthe
releaseofthecarbondioxidegaswhichisgeneratedbythatreaction.The
differentbakingacidswhichmaybeusedinthemanufactureofcakebatters
havedifferentratesofreaction(see
Section2.6.9
).Ifaso-calledfast-acting
acidisused,thentheevolutionofcarbondioxidewouldoccurearlyinthe
battermixingstage.Althoughthebatterisbeingagitated,thereisapotential
forthatcarbondioxidetobelosttotheatmosphereandnotabletocontrib-
utetotheexpansionofthecakeintheoven.Bydelayingtheadditionofthe
sodiumbicarbonatetolaterinthemixingprocess,thepotentialforlosing
thepotentialforbatterdeaerationwhichcanoccurduringthestorageofthe
batterifitisstirred,orwhenitisbeingpumpedthroughpipeworkorwhen
itisbeingdepositedbeforebaking.
Apracticalconsequenceofusingthedelayed-sodamethodformixingcake
battersisthatthecombinedlevelofbakingacidandbicarbonatemightbe
reduced.Thiscouldhaveadvantagesinthecurrentclimateofseekingto
reducethelevelofsodiuminthebakeryfoods(see
Section2.5.4
).
Eachbakingacidafterreactionwiththesodiumbicarbonateleaves
behindadistinctivelytastingsalt;noteveryonelikesthephosphateafter-
tastewhichischaracteristicofmanybakingpowders.Moretraditionalbak-
ingacids,suchastartaricacid,tendtobefast-actingincombinationwith
tosuchacidsandmodifytheflavourprofileofyourproducts(andalso
reducesodiumlevelsinsomecases).
Thespecificationofhotwateristoencouragetherapiddissolutionofthe
sodiumbicarbonate.Thiswasprobablymorerelevantmanyyearsagowhen
theparticlesizeofsodiumbicarbonatewastypicallycoarserthanthatof
today.Ifyouareusingafinelydividedformthenyoumayfindthatyoucan
readilydissolvethesodiumbicarbonateinwaterataround20

C;thiswill
havetheadvantageofnotaffectingthefinaltemperatureofthecakebatter.
Undissolvedandunreactedparticlesofsodiumbicarbonateoftenshowas
darkbrownoryellowspotsonthecrustormoreofteninthecakecrumb.
Cakes,SpongesandMuffins
Chapter|5
285
5.41WEHAVEBEENEXPERIENCINGPROBLEMSWITH
COLLAPSEOFOURSPONGESANDWICHESWHICHLEAVES
THEPRODUCTWITHADEPRESSIONFORMINGONTHETOP
OFTHECAKEANDANAREAOFCOARSECELLSTRUCTUREIN
THECRUMB.WHATCAUSESTHISPROBLEM?
Theareaofcoarsecellstructurethatyouhaveobservedinyourcollapsed
beobservedinthecrumbeventhoughthetopofthecakehasnotcollapsed.
Theprimarycauseofyourproblemisinstabilityandprematurecoales-
cenceoftheairbubblesinthebatter.Whenthespongebatterreachesthe
ovenandthegasbubblesbegintoexpand,itisimportantthattheydonotcoa-
lesceuntiltherightmomentinthelaterpartofthebakingprocess.Toremain
expandundertheinfluenceofheatandduetothecarbondioxidegaswhichis
diffusingintothemastheresultoftheacceleratingbakingpowderreaction.If
thestabilisingmaterialisnotabletostretchsufficiently,thenitrupturesallow-
ingadjacentgasbubblestocoalesceandformlargerones

Thecoarsecom-
ponentofthecellstructure.Atthesametime,thedisplacedstabilising
materialwilljoinwithothermaterialstoformareasdevoidofaircells

the
thickcellwallmaterialyouseewhichalsolooksdarkerincolour.
Althoughthereisonlyoneprimarycause,therearemanycontributing
factors.Theyincludethefollowing:

Thepresenceoftracesoffatoroilinanon-emulsifiedspongerecipe.
Ensurethatalltracesoffatoroilareremovedfromthemixingbowland
usehotorboilingwatertowashtheutensilsclearofoilandfattraces.

Toolittleemulsifierinanemulsifiedspongerecipe.Tryincreasingthe
leveltoabout0.75%ofthebatterweight(see
Section2.5.6
).

Toomuchbakingpowderintheformulation(see
Fig.5.6
).Reducethe
bakingpowderlevelandifthecakelacksvolumeincreasethemixing
timetolowerthebatterrelativedensityorincreasetheemulsifierlevel.

Batterrelativedensitytoolow,especiallywithlowlevelsofemulsifier.
Althoughthebattermaybestableatlowtemperatures,itisduringthe
bakingthatbubblestabilityismostimportant.

Theparticlesizeoftheflourbeingtoolarge.
286
BakingProblemsSolved
Onefactorwhichisknowntocontributetothisproblemisthepresence
ofanti-foamingagentssuchassilicones.Evenlevelsaslowas2ppmhave
beenshowntoinducecoreformationinspongecakes.Theeffectivelevel
dependstosomeextentonthelevelofemulsifierpresent,but5ppmsilicon
willdestabilisemostspongecakesbatters.Tracesofsiliconemaycomefrom
anumberofdifferentsources.Inthepast,wehaveencounteredtracesofsili-
coninthefollowingsources:
Barrierscreamsusedforhands.
FIGURE5.6
Effectofbakingpowderlevelinsponges.
Cakes,SpongesandMuffins
Chapter|5
5.42RECENTLY,WEHAVEBEENEXPERIENCINGPROBLEMS
WITHOURSPONGESANDWICHCAKESASSUMEAPEAKED
SHAPEDURINGBAKING.WEHAVENOTCHANGED
INGREDIENTSORRECIPE.CANYOUSUGGESTWHYWEARE
HAVINGTHISPROBLEM?
atedtothebakingconditionsratherthan
theingredientsorrecipe.Asfarasthebakingconditionsareconcerned,therecan
beanumberofdifferentreasonswhythisproblemshouldoccur.Oftenthecondi-
tioniscausedbytoorapidaheattransfertothebatter.Inallbakedproducts,heat
istransferredfromthesurfacetothec
entre,andinthecaseofroundproducts,
muchoftheheattransferisalongtheradiifromouteredgestocentre.Inthecase
ofaroundsponges,thesurfaceareaislargerelativetoitsthicknesssothatasmall
portionofbatterinthecentreisthelasttobakeandtheconsiderableexpansion
forceswhicharepresentexploitther
adialeffectandforcethespongetopeak.
Themostobvioussourcesoftoorapidarateofheattransferareasfollows:

Toohighabakingtemperatureintheoven;cakepeakingisentirely
dependentonbakingtemperatureandindependentofbakingtime.The
solutionistolowerthebakingtemperature,butyoumayhavetoalso
increasethebakingtimetoremovesufficientwaterfromtheproductto
avoidproblemswithshorteningproductmould-freeshelf-life.

Excessivetopheat,particularlyindeckovens.Thehighradiantheatcom-
ponentinsuchcasesactsliketoohighabakingtemperature.Insuchcases,
thebakingtemperaturemayappeartobesatisfactory.Ifyoucannotbal-
ancetheheatcomponentsinyouroven,steamingthechamberbeforeyou
arereadytobakeisagoodwayofremovingexcessradiantheat.

Inthecaseofovenswhichbakebyforcedairconvection,toohighanair
velocitycancausetheproducttopeak.Highairvelocitiesincreased
spongecakepeakingevenwhenthetemperatureisnormal,especiallyif
theturbulenceabovetheproductishigh.
Otherpossiblereasonsfortheproblemincludethefollowing:

Over-treatmentoftheflour,eitherfromexcessivechlorinetreatment(see
Section2.2.18
)orexcessiveheattreatment(see
Section2.2.17
),ifthey
areused.Inthecaseoftheheat-treatedflour,youmightalsoexpectthat
theflourhasaburntodourwhichmaycarrythroughtotheproduct.If
yoususpectthatthismaybethecause,wesuggestyoudiscusstheprob-
lemwithyourfloursupplier.

Alackofcarbondioxidegasbecausethebakingpowderlevelistoolowor
becausetheRORhasbeentoofastandmuchofthecarbondioxidegashas
beenlostbeforethebatterreachestheoven(see
Section5.38
).Changesin
heattransfercanalsoaffecttherateofreleaseofcarbondioxide.

Insufficientmixingsothattherearetoofewgasbubblenucleiispresent
inthebatterforcarbondioxideinflation.
288
BakingProblemsSolved
5.43WEAREHAVINGPROBLEMSWITHTHEBOTTOM
CRUSTOFOURSPONGECAKEPRODUCTSBECOMING
CORNERSOFTHEPRODUCTBECOMEROUNDEDANDTHE
TEXTURECLOSE.CANYOUOFFERANYEXPLANATIONFOR
THESEPROBLEMS?
Yourproblemcomesfromalackofcarbondioxideintheformulationeither
becauseyouareaddingtoolittlebakingpowderorbecausetoomuchhas
beenlostbeforetheproductreachedtheoven,oryouaremixingthebatter
fortoolong.
andlighttextureinthebakedproductrequirestheevolutionofbakingpow-
derintheoventoinflatetheairbubbleswhichhavebeenincorporateddur-
ingmixing.Eventhoughtheairbubblesexpandundertheinfluenceofheat
intheoventheirdegreeofexpansionislimitedby
CharlesLaw
,i.e.,to
1/273oftheirvolumeforeach1

K(forpracticalpurposes1

K
5
1

C).The
evolutionofcarbondioxideprovidesincreasesingasvolumesfarinexcess
ofthatobtainedpurelyfromthetemperatureeffect.
Asthespongebatterexpandsduringheatingitsrelativedensitychanges
andthisaffectstheheattransferrateintothebatter.Batterswithhighrela-
tivedensities,i.e.,lowgasvolumes,bakefasterthanthosewithlowrelative
densities,becausethegasesinvolvedactlikeaninsulatingmaterial.Thusthe
moregasthatisevolvedduringbaking,theslowertheheattransferrateand
thisleadstomoreuniformexpansionofthebatter.
Steamisalsogeneratedduringthebakingprocess.Thisrequiresthatthe
temperatureintheproductexceeds100

C.Thepresenceofdissolvedsugars
raisestheboilingpointoftheaqueousphaseinsponge(
CauvainandYoung,
2008
ofsteamwhichareprogressivelyevolvedfromthebatterastheheatpene-
therestoftheproduct.Thereisalsoabuildupofsteamattheangleofthe
baseofthepananditssidewhichpreventsthebatterflowingintothatarea.
Theroundingofthisareaoftheproductisoftenreferredtoaschamfering.
TherateatwhichcarbondioxidegasisevolveddependsontheROR
Section2.6.8
).
Thiscanberegulatedeitherbychangingtheacidtypeoritsparticlesize.In
thelattercaselargerparticlesareslowertoreact.
Cakes,SpongesandMuffins
Chapter|5
289
Wesuggestthatyoufirstinvestigatetheeffectofraisingthelevelofthe
bakingpowderthatyouareusing.Thisusuallysolvestheproblem.Ifitper-
siststhenyouaremostlikelyusinganacidwhichistoofast-acting,andwe
suggestthatyouchangetoaslowerone,aroughguideforchoosinga
suitableacidis:

Fast-actingacids

Acidcalciumphosphate(monocalciumphosphate),
tartaricacidandcreamoftartar(potassiumhydrogentartrate).

Slow-actingacids

Sodiumacidpyrophosphateandsodiumacidalu-
miniumphosphate.
Thebakingpowderreactionratecanalsobecontrolledbyusinganacid
orsodiumbicarbonatewithalargerparticlesize,however,youmustensure
thatunreactedcomponentsarenotleftbehindinthebakedproductasthis
canleadtoflavourandcolourproblems.
Ifyoumixthebatterfortoolong,thenthecarbondioxidegaswhichis
beingevolvedduringthemixingprocessmayescapefromthebatterrather
thandiffusingintotheairbubbles.
CauvainandCyster(1996)
showedthat
thiscouldhappenevenwhenusinganapparentlyslowactingacidlike
sodiumacidpyrophosphate.
References
Cauvain,S.P.,Cyster,J.A.,1996.Spongecaketechnology.CCFRAReviewNo.2.Campden
BRI,ChippingCampden,UK.
Cauvain,S.P.,Young,L.S.,2008.BakeryFoodManufactureandQuality:WaterControland
Effects,seconded.Wiley-Blackwell,Oxford,UK.
290
BakingProblemsSolved
5.44WHENMAKINGSPONGEDROPS,WEFINDTHATTHE
LASTONESTOBEDEPOSITEDARENOTASGOODASTHE
FIRSTONES.WHYISTHIS?
Onceabatterhasbeenmixed,changesinitspropertiesoccurwithstanding
time.Thenatureofthesechangesvariesaccordingtothemannerinwhichit
istreatedandthelengthoftimewhichelapsesbeforeitisdeposited.The
mainchangeisrelatedtothestabilityoftheairbubblesinthebatterandthe
evolutionofcarbondioxidegasfromthebakingpowderintheformulation.
Oncemixingstarts,theacidinthebakingpowderbeginstodissolveand
reactwiththesodiumbicarbonatethatispresent.Therateofthereaction
dependsonthetypeandnatureoftheacid(see
Section2.6.8
)andthetem-
peratureofthebatter.Thereactionproceedsmorerapidlyathighertempera-
reactionhasbegun,thecarbondioxidegasdiffusesintotheairbubblesin
thebatterandtheybegintoinflate.Somemaybecomesolargethattheycan
riseinthebatterandescapeatitssurface.Thestabiliserinthebatter(e.g.,
emulsifiers)helpspreventthisfromoccurring.
Asthebatterstandingtimebeforedepositingincreases,morecarbon
dioxideisevolved,andeventually,someofitcanescapefromthebatter.If
toomuchofthecarbondioxideislostthebatterrelativedensitybeginsto
increase,thatis,thebatterbecomeslesswellaeratedandthespongedrops
depositedfromthisportionwilllosevolume.Thelengthoftimewhichhas
toelapsebeforethissituationisreacheddependsontheparticularbaking
acidbeingusedbutcanoccurwithallacids.Thepotentialforde-aeration
ofthebatterincreasesifthebatterisagitatedorsubjectedtosheartoany
significantdegree.Thelongerthatthebatterstandsthegreaterwillbethe
potentialdeaerationeffectfromanyagitation.
Wesuggestthatyouexaminethelengthoftimethatthebatterstandsand
seeifthiscanbeshortened.Thismayrequiretheproductionofsmaller
batchesmixedmorefrequently.Avoidexcessiveagitationofthebatteronce
prepared,e.g.,trytominimisethedegreeofscrapingdownofhoppers
becausethisincorporatesoldbatterwhichcontainslessgas.Alternatively,
considerusingasloweractingacidinyourbakingpowder.
Cakes,SpongesandMuffins
Chapter|5
291
5.45FROMTIMETOTIME,WEEXPERIENCEPROBLEMS
WITHSWISSROLLSCRACKINGONROLLING.CANYOU
HELPIDENTIFYTHECAUSESOFTHEPROBLEM?
shouldhaveauniformthicknessafterbakingandshouldbesufficientlyflexi-
bletowithstandtherollingprocess.Controlofanumberofdifferentrecipe
andprocessfactorsarethereforeimportantifyouaretoavoidproblemswith
therollscracking.Wesuggestthatyoulookcloselyatthefollowingaspects.
fromchangesinbatterdensity,lowerorhigher,fromchangesinmixing
timesorfromdifferentlevelsofairinjectionincontinuousmixers.
Asbakingpowderactionmakesasignificantcontributiontorollthick-
nessyoumaywishtoexaminethelevelthatyouuse.Therateatwhichthe
carbondioxideisreleasedvariesaccordingtothetypeofacidthatisbeing
used(see
Section2.6.8
)andyoumaywishtocheckthatyouareusingthe
sameacideachtime.Thereissomereleaseofcarbondioxidegaswhilethe
batterstandsbeforedepositing,soanysignificantvariationinbatterstanding
timecanhaveaneffectonfinalproductvolume.
Youshouldcheckyourdepositweightcontroltoensurethatthereareno
significantvariations.Rememberthatthedepositweightforagivenunit
areawithSwissrollbatterislowandsoevensmallvariationsmayhavea
significanteffect.
Avoidunnecessarydryingoftherollduringbaking.Thismaycomefrom
longerbakingtimes,higherbakingtemperaturesorhigherairvelocitiesin
sometypesofoven.Variationsinbatterformulationandaerationwillalso
haveaneffectonthefinalrollmoisturecontent.Rememberthatathinner
292
BakingProblemsSolved
5.46WHATARETHEKEYELEMENTSTOCONSIDERWHEN
MAKINGCHOCOLATECAKESWITHCOCOAPOWDER?
Theuseofthetermchocolatetodescribeacakevariesalittlearoundthe
worldandisoftenregulatedinsomeway.Forexample,intheUnited
Kingdom,chocolatecanonlybeusedasacakedescriptorifthefinalproduct
containsnotlessthan3%dry,non-fatcocoasolids.Thisisusuallyachieved
throughtheadditionofcocoapowderandwhencalculatingtheleveltouse
inarecipeallowancemustbemadeforvariationsinmoisture(usually
Chapter|5
5.47WEHAVEBEENMAKINGCAKEMUFFINSANDFIND
THATWHENWECUTTHEMOPEN,THEYHAVELARGE
VERTICALHOLESINTHECRUMB.WHYISTHISANDHOW
DOWEELIMINATETHEM?
Theholesthatyouhaveseenareoftenreferredtoastunnelholesandrun
verticallyfromthebaseofthemuffintowardsthepeaktop.Asheatbegins
nise.Atthistime,thereisasignificantincreaseinbatterviscosityinthe
outerareasofthedeposit.Abovetheseareasofhighviscosity,thebatteris
stillrelativelyfluidandcanexpandupwardseventuallyburstingthoughthe
topcrustandcausingthemuffintoformapeakedshape.
Theexpansioncomesfromtheevolutionofsteamandthegenerationof
carbondioxidefromthereactionofthebakingpowdercomponentsandtheir
thermalexpansion.Itappearsthatthetunnelholesfirstforminareasofthe
batterwherethebatterisclosetogelatinisingandcoalescenceoftheprevi-
oussmallgasbubblesisbeginningtooccur.Theselargerbubblesbecome
buoyantandtrytorisetowardsthesurfaceofthemuffin.Thepressurein
theformationofthebaseofthetunnelhole.Theportionsofbatterwhich
Fig.5.7
).
Asbatterviscosityandgelatinisationareimportantindeterminingthedevel-
opmentofthetunnelholes,youcouldeliminatethembychangingyourrecipe,
particularlybyre-balancingyoursugartowaterratiowithanincreaseinthe
levelofwater.However,thesetypesofholeshavebecomesocharacteristicof
muffinsthateliminatingthemmayaffectconsumersperceptionsofyourprod-
uctqualitysoproceedwithcaution.Ifyouaregoingtore-balanceyourformula,
youmayprefertocalltheproductbyanothername.
FIGURE5.7
Tunnelholesincakemuffins.
294
BakingProblemsSolved
5.48WHYDOSOMEOFOURCAKEMUFFINSLEANTOONE
SIDEDURINGBAKING?
Duetothecombinationofrecipe,de
positweightsandpandimensions,
cakemuffinstendtoformalargebulb
ousheadwhichslightlyoverflows
thesidesofthesupportingpan.Usually,thebulbousheadislocatedmore
heightinthepan.Theexpansionofthisportionofthebatterprovidessuf-
ficientforcetoencouragetheformationofthebulbousheadandbreakon
thetopcrust.
Thecontrolofheatinputinovenisakeyelementinthedeliveryofa
uniformshapewithcakeproducts.Al
lbakedproductsreceiveheatattheir
surfaceswhichistransmittedthroughtotheircentres.Therateofheat
transferdependsonmanyfactorsre
latedtodoughorbatterdensity,
dimensionsandovenconditions.Cake
battersarelessviscousthanbread
orcookiedoughsandasheatisslowlybeingconductedtotheproduct
centre,itispossibleforconvectioncurrentstoforminthebatterbeforeit
includingflourtreatment(
CauvainandYoung,2006
)andthedimensions
ofthecake.Convectioncurrentsaremorelikelytooccurinproducts
whicharerelativelythickbycomparisonwiththeirSAs(e.g.,loafand
slabcakes).
Whenproductsarebakingintheoven,itisimportantthatthereissuf-
ficientairmovementaroundthemtohelpwiththeuniformtransferof
flowcanbereducedandthecrustoftheproductwilltakelongertoform
onthatpartoftheproduct.Insuchc
ases,theexpandingbatterwilltend
tomoveinthedirectionwherethecr
ustisweakestandyieldaproduct
whichleans(
Fig.5.8
).Wesuggestthatyoulookcloselyatthespacingof
yourcakepansonyourtraysandthewayinwhichtheyareplacedinthe
oven.
Cakes,SpongesandMuffins
Chapter|5
295
Reference
Cauvain,S.P.,Young,L.S.,2006.BakedProducts:Science,TechnologyandPractice.Blackwell
Publishing,Oxford,UK.
FIGURE5.8
Leaningcakemuffins.
296
BakingProblemsSolved
5.49WHATISBAUMKUCHENANDHOWISITMADE?
BaumkuchenisaspecialitycakemuchlovedbyGermans.Ittakesitsname,
meaningtreeorlogcake,fromthewaythebatterwasoriginallydeposited
andbaked,layerbylayeronathinlogwhichwasrotatedoveranopen
woodfire.Itissaidtohaveitsoriginswiththeancientcivilisationsofthe
GreeksandRomans.Itisbelieved,theRomansbroughtthetechniquefor
producingtheBaumkuckenastheyconqueredNorthernEurope,andin
Germany,thetechniqueswerepractisedandenhancedtogivethemodern
dayBaumkucken.
Atypicalrecipeis:
500gbutter
500gsugar
1500gegg
500gflour
Therecipecanbevariedbyaddingotherfillingssuchasgroundnuts,
honey,marzipanandrumorbrandy.
plishedbyadjustingtheheatsourceand/orthedistanceofthecakefromthat
source.Theregulationoftheflamesduringbakingisveryimportantand
Chapter|5
ofstringholdthepaper.Whilststillintheoven,thebakedcakeisdecorated
withapricotpureewhichservesasaglaze.Otherfinishessuchasfondantor
chocolatecanbeaddedafterwards.Therolleristhenremovedandtheentire
cakecutupintoringsorusedinanuprightpositionasaspecialitycakefor
Easterorotherfestiveoccasion.
Sometimes,thecakeisremovedimmediatelyfromtherollerandcutinto
Chapter6
Biscuits,Cookies,Crackersand
Wafers
6.1HOWIMPORTANTARETHEDOUGHANDBATTER
TEMPERATURESINBISCUIT,COOKIE,CRACKERANDWAFER
MAKING?
Thetemperatureofbiscuitdoughsandbattersisimportantincontrollinga
numberofthekeychemicalreactionsandininfluencingtheprocessingof
thedough.Thetemperaturerequirementsofbiscuitandcookiedoughsare
quitediverse,sowewilldiscussthemunderfivedifferentheadings;semi-
andotherlaminatedbiscuitsandwaferbatters.
Thedoughrheologicalpropertiesarestronglyinfluencedbytheflourproper-
tiesandthedevelopmentoftheglutenstructureinthedoughduringmixing.
thecutpiecestoshrinkbackaftercuttingorduringbakinggivingmisshapen
products.Thisproblemismostcommonlyrelatedtohighlevelsofgluten
formationintheinitialdough.Ingeneral,thewarmerthedoughthesofter
L
-cysteinehydrochloride(see
Section
2.2.7
)orproteolyticenzymesmaybeaddedtohelpreducetheelasticityof
thedough.Itisworthnotingthattheactionofbothreducingagentsand
proteolyticenzymeswillbetemperaturesensitiveandthathigherdoughtem-
peratureswillencouragegreaterchemicalandbiologicalactivity.Thisisan
levelofactivityresultingfromthecombinationofhighertemperaturesand
recycletimescancauseconsiderablechangesindoughrheological
properties.
299
BakingProblemsSolved.DOI:
http://dx.doi.org/10.1016/B978-0-08-100765-5.00006-0

2017ElsevierLtd.Allrightsreserved.
issignificantresistancebythedoughduringmixing,whichinturnmeans
energytransferandtemperatureriseduringdoughmixinganditscontribu-
tiontodoughdevelopmentiswell-understoodinthecaseofbreadmaking
(
CauvainandYoung,2006a
isrecognisedthatsignificanttemperaturerisesdooccurduringmixing.
Manley,2000
).
Short-doughrotarymoulded
Thehigherlevelsofsugarandfatusedinshort-doughbiscuitsrecipes
limittheformationofaglutenstructureinthemixeddough(
Cauvainand
Young,2006b
).Thelevelandthechoiceofthetypeoffatbeingusedinthe
dough,thewayinwhichitwillprocessandtheeatingqualitiesofthebaked
product.Themeltingprofileandthefinalmeltingpointofthefatplaya
Highmeltingpointfats(e.g.,above40

C)tendtoyieldbiscuitswitha
waxymouthfeel,whereaslowmeltingpointfatstendtoconferoilychar-
acteristicstothebakedproducts.
themanufactureofshort-doughbiscuits.Commonly,themixingprocessfor
shortdoughscomprisestwostages;thefirstoneisoftendescribedasa
creamingstageinwhichthefatismixedwiththesugarandotheringredi-
entsbeforetheflourisadded,andthisrequiresthefattohavetheappropri-
atemeltingprofiletogivegooddispersionandaidwiththeincorporationof
air.Carefulcontrolofthedoughtemperatureduringmixingisrequiredto
maintainthekeyrolesofthefatintherecipe,andinthemanufactureof
short-doughbiscuits,finalmixtemperaturesaremuchlowerthanwithsemi-
Wire-cutanddeposited
Wire-cutcookiedoughsareofasimilarconsistencytoshort-dough
biscuits,butoftentherecipeswillco
ntainparticulateinclusionssuchas
chocolatechipsandnuts.Theconsiderationswithrespecttotheimpor-
tanceofdoughtemperaturesaresimilartothoseforshort-dough
biscuits.
Depositedbiscuitsaresimilartocakebatters,sothecontrolofbatter
temperatureisimportantforthecont
rolofgasproductionbythebaking
powderandthebatterviscosity.Theb
attertemperature
susedwillbelower
thanthoseusedinthemanufacture
ofwafersbecausethereisnoyeast
present.
Crackersandotherlaminatedbiscuits
Manycrackerformulationscontainyeastanduseperiodsoffermentation
(see
Section6.19
)followedbylaminationofthedoughtoachievetheir
300
BakingProblemsSolved
characteristiccrispandflakystructures.Thereareanumberofvariationson
thefermentationsystemincludingspongeanddough,straightdoughand
continuousfermentationsystems.Inallcasescontrolofthedough,tempera-
tureisveryimportanttooptimisethecontributionbytheyeasttogas
production.
Incracker-makingprocesseswhichemploylongfermentationtimes,there
isthepotentialforsignificantflavourdevelopment.Theaddedyeastwill
contributetothefinalflavourprofilebutequallyimportantwillbethecontri-
butionfromthenaturallyoccurringlactobacilliandothermicroogansims.In
somecases,aspecificcultureoflactobacillimaybeaddedatthestartof
mixingtoachieveaspecificflavourprofile.Thetemperatureusedinthefer-
mentationprocessesassociatedwithcrackerproductionmaybevariedto
encourageaparticularflavourprofile.
Waferbatters
Inthepreparationofwaferbatters,thetemperaturewillplayanimportant
Chapter|6
ProductTemperaturerangefor
doughorbatter(

C)
Wafers22

32

46
Short-doughrotarymoulded18

22
Wire-cutanddeposited16

24
Crackersandotherlaminatedbiscuits30

38
References
Cauvain,S.P.,Young,L.S.,2006a.TheChorleywoodBreadProcess.WoodheadPublishingLtd.,
Cambridge,UK.
Cauvain,S.P.,Young,L.S.,2006b.BakedProducts:Science,TechnologyandPractice.
BlackwellPublishing,Oxford,UK.
Manley,D.,2000.TechnologyofBiscuits,CrackersandCookies,thirded.Woodhead
PublishingLtd.,Cambridge,UK.
302
BakingProblemsSolved
6.2WHATISVOLANDWHATISITSFUNCTIONIN
BISCUITSDOUGHS?
Volisabakerstermwhichisappliedtoammoniumcarbonate.Itisusedas
anaeratingagentanddoesnotrequiretheadditionofanacidtoevolvecar-
bondioxide.Italsodiffersfromotheraeratingagents,inthat,itevolves
almostnogasinthecoldanddecomposesundertheinfluenceofheatto
yieldthreegases;ammonia,carbondioxideandwatervapour(steam).
Theevolutionofammoniarestricts
theuseofvol.Ammoniaisreadily
solubleintheliquidphaseofdough
s,pastesandbattersandwillremain
intheproductifsufficientwater
remainsafterbaking.Thisisthe
casewithcakeswheretheuseofvolwillleaveanunpleasantammonia
tasteandsmell.Inbiscuits,however
,thedegreeofheatinputrequiredto
driveoffalmostallofthewaterfromthedoughensuresthatthemajority
oftheammoniaisalsodrivenoffsothattheeffectontasteandflavouris
notdetectable.
Thereareanumberofreasonswhyvolhasbeenusedinthebaking
industry,including:
Thevolumeyieldofgasesisconsiderableforagivenweightofmaterial.
Chapter|6
6.3ABATCHOFOURBISCUITSCONTAININGOATMEAL
HASDEVELOPEDASOAPYAFTER-TASTEWHICHMAKES
THEMUNPALATABLE.WHYISTHIS?
Thesoapytastethatyouobserveisalmostcertainlytheresultoflipase
enzymeactivityineitherthedoughbeforebakingorinthebakedproduct
duringstorage,possiblythroughpost-bakingcontamination.
Oatsarepronetothisproblemduetothehighleveloflipaseenzyme
activitywhichisnaturallypresent.Lipasesplitsfatsintofattyacidswhich
reactwiththesodiumbicarbonatetoyieldthesoapyflavour.Themostcom-
monwayofavoidingthisproblemistoonlyuseoatproductsinwhichthe
lipaseactivitieshavebeeneliminated.Thisisachievedbysteamingtheoats,
andyoushouldspecifythistoyoursupplier.Steamingshouldnothaveany
adverseeffectsonthefunctionalityoftheoatswhichislimitedinbiscuit
making.
Youshouldalsoexamineyourdoughmixingandprocessingtoensure
thattherehasbeennoincorporationofscrapsofolddoughoroneswhich
havebecomeheavilycontaminatedwithmicroorganismswhichalsohavethe
potentialforconsiderablelipaseactivity.
Ascommentedabove,thelipaseactivitycanhaveamicrobialoriginand
socouldalsocomefrompost-bakingcontamination.Innormalcircum-
stances,thewateractivityofanoatmealbiscuitistoolowtosupportmicro-
bialactivityduetoitslowmoisturecontent.However,iftherehasbeenany
condensationonthesurfaceofthebiscuit,thenthewateractivitymighthave
becomehighenoughtoinitiatethenecessarymicrobialactivity.Youshould
considerwhethertherehasbeenanyopportunitiesforwarmingandcooling
whichmayleadtocondensationinthepack.
Oat-basedproductsmayalsodevelopoff-odoursandbittertastesdueto
oxidativerancidity.Inthecase,th
elowwateractivityintheproduct
encouragestheproblem,alongwithexposuretolightandtracesofcer-
6.4FROMTIMETOTIME,WEHAVENOTICEDAWHITE
DISCOLOURATIONONTHESURFACEOFOURALL-BUTTER
SHORTBREAD.CANYOUEXPLAINWHYTHISOCCURS?
Thediscolourationthatyouhaveobservedisthephenomenoncommonly
referredtoasfatbloom.Itistheformationofsmallcrystalsoffatonthe
surfaceofthebiscuitandoccursmainlyastheresultoftemperaturecycling
duringstorage,thatisperiodsofwarmthandcoldsuchasmayoccurin
un-heatedlocationssubjecttotheeffectsofambienttemperaturefluctuation.
Fatcrystalsmayexistinanumberofdifferentforms(see
Section2.3.1
).
Astheirsizemayassmallas5

m,onlyagglomeratesoffatcrystalscanbe
seenwiththenakedeye.Theformationofcrystalagglomeratesisencour-
agedbyrapidcooling,suchasmightbeexperiencedwhentheproductsare
quicklychilledafterbaking.Similarconditionsmayoccurifawarmproduct
isplacedintoachilledenvironment.Asimilarproblemmaybeseenwith
chocolateswhichhavebecometoowarminperiodsofhotweatherandthen
placedinarefrigeratortocool.
Tominimisetheproblem,youshoul
dexamineyourcoolingtechnique
andtrytocoolmoreslowly,oreliminateforcedaircooling.Alsoconsider
thetypicalstoragetemperaturehistoryoftheproduct,lookingforany
fluctuatingperiodsofwarmthandcoldandeliminate,oratleastminimise
these.
Ifnoneoftheseconsiderationsarerelevant,youmighttackletheproblem
byintroducingasmallportion(sayabout5%)ofalowmeltingpointbutter-
fatfractionoroilintotheproduct.Thiswillhelptoreducethetendencyfor
thefattorecrystallise.
Biscuits,Cookies,CrackersandWafers
Chapter|6
305
6.5WEPRODUCEBISCUIT-CONTAININGPOWDERED
FRUCTOSEWHICHWECREAMWITHTHEFATANDSUCROSE
BEFOREADDINGTHEOTHERINGREDIENTS.RECENTLY,WE
HAVESEENTHEAPPEARANCEOFBROWNSPOTSONTHE
PRODUCT.DOYOUKNOWWHATCAUSESTHISEFFECT?
Themostlikelycauseofyourproblemisassociatedwiththecreamingofthe
fatandthesugars.Itislikelythatsomeofthefructosethatyouareadding
hasbecomesocoatedwithfatthatitcannotdissolveinthelimitedamount
ofwaterthatisavailableinatypicalbiscuitdough.Thisleadstoexcessive
browningduringbaking.
Toavoidtheproblem,youcoulddissolvethepowderedfructoseinthe
doughwaterbeforemixing.Alternatively,youcouldchangetoafructosesyrup,
rememberingtore-balancethesugarsolidsandwatercontentoftherecipe.
Similarbrownordarkspotsmayariseifyouareusingverylargecrystals
ofsucrosewhichdonotdissolvecompletelyandleadtotheproblemsome-
timesdescribedassugarburn.
Darkspotsmayalsooriginatefromundissolvedaeratingacidsinthemix.
Forexample,acidcalciumphosphateissparinglysolubleandcanhydrolyse
onthesurfaceofbakedgoodstogivefreephosphoricacid.Theacidcancar-
bonisecarbohydratesduringbakinggivingrisetodarkspotswherethephos-
phateisconcentrated.Often,theproblemisalleviatedbychangingtoafiner
DURINGSTORAGE,EVENIFTHEYARENOTDISTURBED?
CANWESTOPTHISFROMHAPPENING?
Theproblemyoudescribeistheonecommonlyreferredtoascheckingand
isrelatedtotheunevendistributionofmoistureinthebakedbiscuitor
cracker.Itwasfirststudiedandthereasonsfortheproblemreportedby
DunnandBailey(1928)
.
Afterleavingtheoven,themoistureremaininginbiscuitsandcrackers
isunevenlydistributed;inparticular,theedgesandupperandlowersur-
faceshaveamuchlowermoisturecontentthanthecentre.Duringstorage,
themoisturemigratesfromthehighermoisturecontentcentretothedrier
stressesandstrainsintheproductwhich,becausetheproductisinflexible,
canbeofsufficientforcetocrackthesurface.Insomeseverecases,the
developalongweaknessesintheproductstructure,manyofwhichare
microscopicinsize.
Thebestmeansofavoidingthisproblemistoassureaminimumof
moisturegradientinthebakedproduct.Thiscommonlymeansbakingat
lowertemperaturesforlongertimes.Alternatively,youcanintroduce
immediatepost-bakingdryingusingradio-frequencyormicrowaveheating.
than1%andaveragebiscuitmoisturecontentsintheorderof2

3%.Itis
possibleforbiscuitstoabsorbmoisturefromtheatmosphereiftheyarenot
packedcorrectly,butthisusuallyleadstosofteningofthebiscuitrather
thanchecking.
DunnandBailey(1928)
suggestedthatpartofthecrystallinesucrosebe
replacedwithinvertsugarsyrup.Othersuggestionshavebeenusingalower
proteinflourandsmalleraverageparticlesize,thoughsuchchangesmaynot
besuitableforcrackerproductionwheretheproteinplaysanimportantrole
indeliveringtherelevantdoughrheologyandformationofthelayeredstruc-
ture.
Micka(1939)
suggestedthatraisingthepHtoaround7.0wasusefulin
reducingchecking,andheconsideredthatcarefuluseofreworkwas
necessary.
References
Dunn,J.A.,Bailey,C.H.,1928.Factorsaffectingcheckinginbiscuits.CerealChemistry5,
395

430.
Micka,J.,1939.StudyofcheckingandpHincrackerandbiscuitproduct.CerealChemistry16,
752

764.
Biscuits,Cookies,CrackersandWafers
Chapter|6
307
6.7WEAREMAKINGAGINGERCRUNCHCOOKIE,BUT
FINDTHATWEEXPERIENCEVARIATIONSSIZE.CAN
YOUADVISE?
Variationsinbiscuitsizeoftencomefromvariationsinflowduringthebak-
ingprocess.Thethreemainingredientswhichcontrolflowaresugar,ammo-
niumbicarbonateandflourproteinlevel.
Ifyouwanttoincreaseflowthenyoucan:
Increasesugarorglucosesyruplevel.
Increaseammoniumbicarbonate(vol)level.
Useaflourwithahigherproteincontent.
Ifyouwishtodecreaseflow,thenyoushoulduselowerlevelsofthe
aboveingredients.
Asyouareexperiencingvariationsinflow,thenyoushouldcheckthe
weightsofthethreekeyingredientstomakesurethattheyarebeingdeliv-
eredconsistently.Ifthereisnoproblemwiththeweightsbeingdelivered,
thenyoushouldlooktotheflourqualities.
BakingProblemsSolved
6.8WHENMAKINGGINGERNUTS,WEFINDTHATWEDO
WOULDLIKE.WHYISTHIS?
Thecrackswhichformongingernutsaremostlyrelatedtothelevelandbal-
anceofsugartypesbeingused.Youshouldtryincreasingthelevelofcoarse
sugarorreducetheleveloffinesugarintherecipe.
Theovenhumiditycanalsoaffectcrackformationandanincreasemay
beofsomehelp,especiallyifyoucanintroducethehumidityintothefirst
sectionofamulti-sectionoven,theproductsmayexhibitpoorcracking
becausetheyareflowingtoomuch(see
Section6.7
).
Biscuits,Cookies,CrackersandWafers
Chapter|6
309
6.9WEARETRYINGTOMAKESOFT-EATINGCOOKIESAND
AREHAVINGADEGREEOFSUCCESSWITHTHERECIPETHAT
WEAREUSING.THEPRODUCTSARENOTEXPECTEDTO
HAVEALONGSHELF-LIFE,BUTWEFINDTHATTHEYARE
GOINGHARDTOOQUICKLY.CANYOUSUGGESTANY
WAYSOFEXTENDINGTHEPERIODOFTIMETHATTHE
COOKIESWILLSTAYSOFTEATING?
Soft-eatingcookiesareusuallybakedtohighermoisturecontentsthanmany
typesofbiscuitsandcookies;moisturecontentsmayrangefrom6to12%
comparedwithlessthan5%withmoretraditionalbiscuitforms.Thishigher
moisturecontenthelpstoconfersomeofthesoftereatingcharacterthatyou
areseeking.
slightlythickercookiesthanyouareusedto.Thisapproachwillmeanthat
nessandchewinessofthecookie.Therewillbeamoisturegradientinthe
bakedcookiewiththeupperandbottomcrustsandtheedgeshavinglower
moisturecontentsthanthecentre.Graduallyduringstorage,youwillfind
thatthemoisturefromthecentreofthecookiewillmigratetotheregionsof
lowermoisturecontentwithsomelossofthesoft-eatingcharacter,butthey
willhaveasoftertexturethanstandardcookies.
Therateatwhichthismoistureequilibrationoccursdependsonanumber
offactorsbutisespeciallyaffectedbythemoisture-permeabilityofthepack
characterthatyouareseekingyoushoulduseawrapperwithalowmoisture
vapourtransitionrate(see
Section11.7
)whichlimitsmoisturelosses.You
shouldalsochecktheintegrityofthepacksealsasmoisturecanreadilypass
outofthepackthroughanysmallgaps.
Intheoven,itisgenerallyrecognisedthatpartofthesugarwhen
heateddissolvesintherecipewaterandmeltstoformanamorphousglass
(asuper-cooledliquid).Thissugarglasscontributestocookieflowand
significantlyaffectsthefinalcookieeatingcharacter.Withthelossof
moistureduringbaking,thelevelofwateravailableforkeepingthe
sucroseinsolutionislowered.Asthecookiescoolonleavingtheoven,
someofthesucrosesthatispresentw
illrecrystallisewhichcontributeto
thehardnessoftheireatingcharacter.Ifmoremoistureislostduringstor-
age,moresugarwillrecrystalliseandtheeatingcharacterwillfurther
harden;itisforthisreasonthatitisimportanttorestrictthemoisture
lossesduringstorage.
thecrustregionscanleadtoproblemsofcheckingorthespontaneousbreak-
ingofbiscuits(see
Section6.6
).Checkingismorecommonlyaproblem
310
BakingProblemsSolved
crackertypes(
CauvainandYoung,2008
).Youshouldnotexperienceany
problemswithchecking,nevertheless,youshouldwatchoutforanysignsof
theproblem;forexample,anincreaseinthecrumblinessofyourproducts.
Ifyouareincludinganynuts,chocolatechipsorpiecesoffruitinyour
cookies,theyprovidediscontinuitiesorpointsofweaknessinyourproducts
whichcanbeexploitedbythestrainswhicharisebecauseofmoisture
migrationwithinthecookie.Driedfruitpiecescanalsobeaproblemas
theymayabsorbwaterfromthemoisterareasofthecookieandsomay
increasethelikelihoodforsugarrecrystallisation.
Oneofthewaysyoucanhelpkeepthecookiesoftistoreplacepartof
thecrystallinesucrose(sugar)withnon-sucrosesugarsyrup.This
replacementwillreducethelikelihoodofthesucroserecrystallisationduring
storage.Sugarsyrupswhichmaybeusedincludeglucosesyrupsand
high-fructosecornsyrup.Youwillneedtocarryoutafewtrialstofindan
appropriatelevelofreplacement.Remembertoadjustthewaterlevelinyour
recipetoallowforthewaterpresentinthesugarsyrup(typicallyaround
18

20%).Highlevelsofglucosesyrupmayleadtoexcessivebrowningin
plaincookies,withchocolatecookiesthisshouldbelessofaproblem.You
Reference
Cauvain,S.P.,Young,L.S.,2008.BakeryFoodManufacture&Quality:WaterControland
Effects,seconded.Wiley-Blackwell,Oxford,UK.
Biscuits,Cookies,CrackersandWafers
Chapter|6
311
6.10WEASSEMBLEASELECTIONPACKOFBISCUITSAND
COOKIES,ONEOFWHICHISARECTANGULARPRODUCT
COATEDONTHETOPWITHICING.WHENTHEPACKIS
6.11WEAREEXPERIENCINGDARKBROWNSPECKSONTHE
Chapter|6
6.12WEAREHAVINGSOMEPROBLEMSWITHPACKING
OURROTARYMOULDEDBISCUITLINES.WHENWEMEASURE
THETHICKNESSOFTHEBISCUITS,WEHAVENOTICEDTHAT
SOMEARETHICKERTHANOTHERS.CANYOUSUGGESTANY
Closeexaminationofthesamplesthatyouprovidedshowedthatthemain
problemisnotthatthebiscuitsvaryinthickness,butthatmanyoftheindi-
vidualbiscuitsareinfactwedge-shaped;i.e.,oneedgeofthebiscuitis
thickerthantheopposingedge.Asthebiscuitsarenotnecessarilyuniformly
orientatedatthetimeofpacking,thisiswhatisgivingrisetoyourproblem.
Firstofall,youneedtoestablishifthewedgingisuniformacrosstheoven
tionoftravelalongtheplant.Fromthisaction,youcanestablishtheleading
edgeforfuturetrials.Next,youstackthewholerowofbiscuitsoneontopof
oneanother(withthesameleadingedgeorientation)andseewhichwaythe
stacktilts;thiswilltellyouifthewedgingliesinoneparticulardirection.In
somecases,theoccurrenceofwedgingmaybemorecomplicated,andyou
mayhavetomeasurethetwothicknesses(leadingandtrailingedges)foreach
biscuit.Ifyouareseeingvariationsinthedirectionofwedgingacrossthe
band,youshouldconfirmthisbycollectingseveralrowsofbiscuitstocheck
theorientationofindividuallanes.Thepatternofwedgingthatyouseeinthe
productsleavingtheovenisindicativeofthepatterninthedoughpiecesleav-
ingtherotarymoulder.Onceyouhaveestablishedthispattern,itcanbeused
tocheckprogressineliminatingtheproblem.
Thereareanumberofpotentialreasonsfortheoccurrenceofwedging;
theyincludethefollowing:

Runningtheextractionandmouldingrollsatdifferentspeeds.

Highlevelsofwaterleadingtoasofterdoughwhichismorelikelyto
allowextrusionofthedoughthroughthefrontorrearofthemoulds(i.e.,
formationoftails).

Highlevelsofsyrupinyourrecipe.Rememberifyouareusinghigh
levelsofsyrupyoushouldcompensateforanywaterthatmightbepres-
entintheingredient.

Highlevelsoffatleadingtosofterdough.

Usingalowmeltingpoint(lowsolidindex)fatwhichincreasesthesoft-
nessofthedough.

Higherfinaldoughtemperatureswhichleadtoasofteningofthedough
becauselessoftheaddedfatwillbesolid.

Changesinsugarparticlesize,eitherfinerorcoarser(see
Section2.4.1
)
Youshouldalsolookcloselyatyourextractionrollertomakesureitisnot
worn,especiallyiftheproblemisonlyassociatedwithafewlanesofbiscuits.
314
BakingProblemsSolved
6.13WEAREHAVINGINTERMITTENTPROBLEMSWITH
Chapter|6
Anotheroptionisuseacross-pinningrollerwhichrunsatrightanglesto
thedirectionofpastetravel,andthiswillhelpreducetheunidirection
FIGURE6.1
Surfacecrackingonhigh-sugarcookies.
BakingProblemsSolved
6.14WEAREEXPERIENCINGBLISTERINGONTHESURFACE
smoothsurfaceappearance,thehumidityinthefirsttwoorthreezonesof
theovenneedstobehigh.Thehumidityintheearlystagesofbiscuitbaking
comesmainlyfrommoistureevaporatedfromthebiscuitdoughpiecesthem-
selves.Commonly,humidityisregulatedbytheextractiondampersfittedto
theoven,andtomaintainahighinitialhumidity,theseneedtobefully
closedforthefirstoneortwozones.Ifthisdoesnothavethedesiredeffect,
youmayneedtoconsidertheintroductionofextrahumidityviathesteam
8101214161820
FIGURE6.2
Impactoffatsolidsoncookiepieceweight.
Biscuits,Cookies,CrackersandWafers
Chapter|6
Cavitiesunderthetopcrustmayalsobeassociatedwiththeaerating
agentsthatyouareusing.Largerparticlesofammoniumbicarbonate(vol)
willreleasesignificantquantitiesofgasintheoven,essentiallyblowingthe
doughpieceapart.Checkthattheparticlesizeofyoursupplyofvolhasnot
increasedordissolvethevolinwaterbeforeaddingittothedoughduring
mixing.Formoreinformationonusingvolinbiscuits,see
Section6.2
.
318
BakingProblemsSolved
6.15WEAREMANUFACTURINGSHORT-DOUGHBISCUITS
USINGAROTARYMOULDERANDHAVEBEENOFFEREDAN
ALTERNATIVESUPPLYOFSUGAR.WENOTICETHATTHE
NEWSUGARISMOREGRANULARTHANTHEMATERIALWE
HAVEBEENUSINGPREVIOUSLY;WOULDTHISHAVEANY
EFFECTONBISCUITQUALITY?
Wesuggestthatyouarecautiousbeforeswitchingtothealternativesource
ofsugar.Theparticlesize(coarseness)ofthesugarthatyouusewillhave
effectsonanumberofdifferentdoughandbiscuitproperties.Youneedto
bearinmindthatthewaterlevelstypicallyusedinshort-doughbiscuitsare
suchthatnotallofthesugarthatyouareaddingwillgointosolutionand
undissolvedgrainsofsugarsarelikelytobepresent.Therateatwhichthe
sugarparticleswillgointosolutionisaffectedbytheirparticlesize,with
water.
Waterislostduringthebiscuitbakingprocesssothatthereisevenless
wateravailabletokeepthesugarinsolutionwhentheproductcoolswhich
increasesthepotentialforsugarrecrystallisation.Onceagaintheinitialparti-
clesizeofthesugarhasapotentialeffectascoarser-grainedsugarsaremore
likelytorecrystalliseaslargesugargrainsinthebakedproduct.
Someofthelikelyimpactsofsugarparticlesizeincludethefollowing:

Theappearanceofvisiblesugarcrystalsofthebiscuitsurfacewhenusing
coarse-grainedsugars(thoughinsomecasesthismaybeseenasaposi-
tiveproductcharacter).

Anincreaseinthegrittinessofthebiscuiteatingcharacterwiththeuse
ofcoarse-grainedsugars.

Biscuithardnesstendstoincreaseassugarparticlesizeincreases.

Anincreasedtendencytotheoccurrenceofhollowbasesastheparticle
sizeofthebiscuitsincreases(see
Section2.4.1
).

Variationsinbiscuitflowwithvaryingsugarparticlesize.Thisisamost
importantchangeduetotheimpactonbiscuitdimensions,including
stackheight(thickness),whichwillaffectthesubsequentperformanceof
thebiscuitwrappingequipment.Biscuitflowincreasesastheparticle
sizeofthesugardecreases.

Biscuitdoughfirmnessincreaseswhenusingcoarsersugars,probably
becausethereismorewateravailableforabsorptionbytheflour.

Doughpieceandbiscuitweightstendtoincreasewhenusingcoarser-
grainedsugars.
Biscuits,Cookies,CrackersandWafers
Chapter|6
319
6.16ISITPOSSIBLETOREDUCETHELEVELOFSUGARIN
OURBISCUITANDCOOKIERECIPESWITHOUTAFFECTING
THEIRQUALITY?WHATWOULDBETHEALTERNATIVESWE
COULDUSETOSUCROSE?
Reductionsinthesugar(sucrose)leve
linyourbiscuitsandcookieswill
haveanimmediateeffectondoughhand
lingandthefinalproductquality.
Thisisbecausesucroseplaysanumberofimportantrolesinthemanufac-
tureofbiscuitsandcookies.Inthedough,theeffectonwateractivityis
partofthereasonfortheinhibitionofglutendevelopmentduringmixing.
Inbroadterms,theeffectofreducin
gaddedsucroselevelswouldbelike
changingashort-doughbiscuitrecipetobecomemorelikethatofsemi-
,youmayfinditdifficulttocontinuetorotary
mouldreduced-sugarshortdoughs,
andyoumayexperienceincreased
shrinkageofthepiecesafterrelease
fromthemouldandalmostcertainly
whentheproductsarebaked.Inthebakedproduct,sucrosemakesimpor-
tantcontributionstopr
our,flowandshapein
cookiesandthetextureoftheprodu
ct,particularlythehardnessand
crunchinessoftheeatsotherearequiteafewconsiderationtotakeinto
account.
Themainfeaturesofthealternativesugarstosucrosearediscussedin
Section2.4.2
.Thecrystallinenatureofsucroseanditsparticlesize(see
Section2.4.1
)areimportantinthecreamingprocesswhichistypicallypart
ofshort-doughmixing.Thesugarcrystalsaidthedispersionoffatthrough-
outthedoughandcontributetosomeairincorporation.Liquidsugarswill
notbeabletomakethesamecontributionassucrose,thoughsomeofthe
sugarswhicharepowderscandeliversomeoftherequiredfunctionality.To
combinationsofsugars,perhapswithacompensatoryre-balancingwithother
recipeingredients,suchasmilkpowders.
Moredifficulttoreplacewillbeimpactthatsucrosehasontheformation
ofthecookiestructureandultimatelyonitstexture.
Manley(2000)
sum-
marisedindiagrammaticformthechangestakingplaceinbiscuitdough
duringbaking.Thebakingtimeforbiscuitsismuchshorterthanthatofcom-
monbreads,butthereisstilltimeforasimilarseriesofchangestooccur;
caseofbiscuits,therelativelylowaddedwaterlevelsandshortbakingtimes
probablymilitateagainstasignificantdegreeofstarchgelatinisationinthe
structureformationprocesssothatreducingorchangingsugarlevelsisnot
likelytohavethemajorimpactthatitdoeswithcakebattersthoughyoucan
stillexpectsomechangesinbiscuitproperties.
Moreimportantinthecontextofstru
ctureformationandtexturefor
biscuitsandcookiesistheformationofasuper-saturatedsugarsolutionin
theoven.Thesolubilityofsucroseis
highandincreasesdramaticallyas
320
BakingProblemsSolved
thedoughpiecetemperatureincreases.Theformationofthissuper-
saturatedsugarsolutionthroughoutthedoughmatrixcontributestothe
expansionofbiscuitsandcookiesintheoven,butasthestructurebegins
tobecomeporous,theescapinggasle
adstocollapseofthestructureto
yield(usually)athinfinalproduct.Commonly,thiscollapseoccursinthe
oven,dependingonsugarlevel.Insomebiscuitandcookietypes,thecol-
lapsemaynotbegintooccuruntilthep
roductiscoolingafterithasleft
theoven.
Aswellascontributingtotheexpansionoftheproductthesuper-
saturatedsugarsolutionwhichisformedintheovenalsopermitsconsider-
ablefloworspread,andthisspreadneedstobecontrolledtomaintainfinal
productcharacteristics.Astheproductcools,thesugarsolutionsolidifies
andbecomesrigid,oftenformingacharacteristicallycrackedsurface(see
Fig.6.1
).Theimpactofthedifferentsugarsolubilitiesandtheireffecton
productflowwillbeanimportantfactortotakeintoaccountwhenreformu-
latingforlowersucroselevels.
Thecrunchinessandcrumblyeatingcharacterofmanycookieproductsis
adirectresultofthehighlevelsofrecipesucrose,andreductionsinsugar
levelswillresultinthelossofthoseeatingcharactersandahardertexture.
Inmanyhigh-sugarproducts,therecrystallisationofsugaroncoolingresults
inweakpointsinthecookiestructureandcontributestotheshortnessofits
texture.Someofthiseffectcomesfromstartingwithaproportionofcoarse
sucroseparticlesintherecipe,mostalternativesugarsandsugarreplacers
arenotavailablewiththesamerangeofcrystallineformsassucroseandso
arenotabletomakeasimilarcontributiontotexture.
Reference
Manley,D.,2000.TechnologyofBiscuits,CrackersandCookies.WoodheadPublishingLtd.,
Cambridge,UK.
Biscuits,Cookies,CrackersandWafers
Chapter|6
321
6.17WEWOULDLIKETOREDUCETHELEVELOFFATIN
OURBISCUITRECIPES.HOWCANWEDOTHIS?
Areductionoffatwillleadtochangesinprocessingrequirementsduetothe
potentialforgreaterglutenformationinthedoughandanincreasedriskof
shrinkageduringprocessingandbaking.Asthefatlevelinabiscuitrecipeis
reduced,thereisaprogressivelossofproductweight,see
Fig.6.2
.Thefat
alsocontributestotheshortnessoftheeatingquality.Therewillalsobean
increasedriskofchecking(see
Section6.6
).Inthemanufactureofcrackers,
thefatcontributestoproductliftaspartofthecrackerdustwhichislami-
natedintotheproduct.
Themostcommonwayofenablingfatreductioninbiscuitmakingis
throughtheadditionofsuitableemulsifiers.Themostcommonlyusedemul-
sifiers(see
Section2.7.6
mono-anddiglyceridesoffattyacids,usuallyreferredtoasDATAestersor
Datem,sodiumstearoyl-2-lactylateandlecithin.
Theratesofemulsifieradditionwouldbeatabout1.5%ofthefatweight
intheoriginalrecipeandthiswouldallowforareductionofaround20%of
theoriginalfatlevel.Forexample,ifthefatlevelwas16%or16gin100g
mix;therateofadditionoftheemulsifierwouldbe0.24gin100gmixand
thenewfatlevelwouldthenbe12.8g.Obviously,whentheingredientper-
centagesareadjustedbacktoa100-gmix,thepercentageoffatwillnotbe
12.8%becausethetotalingredientweightisslightlyless;thenewpercentage
fatlevelin100-gmixwouldbecome13.2%.
Ifyoudoencounterexcessiveshri
nkageduringprocessing,youcan
L
-cysteinehydrochloride(see
Section2.7.7
)ortheadditionofproteolytic
enzymes.
322
BakingProblemsSolved
6.18WHATAREMAINISSUESTHATWESHOULDBEAWARE
OFINTHEMANUFACTUREOFSAVOURYPUFFBISCUITS?
Theprinciplesformanufacturingpuffbiscuitsaresimilartothoseforpuff
Thelattermainlyusecheesetogivetheproductflavourandinsomecasesa
cheese-basedcreamisusedtomakeasandwichsnackproduct.Manyofthe
savouryformsofpuffbiscuitsaresmallinsizeandservedassnacks.
dough.Thesteampressurecreatedbytheevaporationofwaterduringbaking
forcesthedoughlayersaparttogivethecharacteristicflakystructure(see
Section7.1.1
).Thecreationandcontroloftheintegrityofthefatanddough
layersisthereforeanimportantpartoftheliftmechanismforpuffbiscuits.
Ingeneral,thedegreeofliftthatgivessatisfactorypuffbiscuitsisslightly
lessthanyouwouldseekinthemanufactureofpuffpastry.Typically,
around96fatlayersaresuitableforpuffbiscuits.Fewerlayersyieldthick
biscuitswhichareveryflakyincharacter,whereaswithgreaternumbersof
fatlayers,theproductsbecomethinandloseflakinessbecauseofthebreak-
downoftheintegrityofthefatanddoughlayers.
Theleveloflaminatingfatusedintherecipewilltendtobelowerthan
inthemanufactureofpuffpastry.Typically,theleveloflaminatingfatfor
puffbiscuitswillbearound40%oftheflourweightinthebasedough.
Higherlevelsoflaminatingfattendtoyieldbiscuitproductswhichshowa
greaterdegreeofshrinkageandwhichareveryfragile.
Arangeoffloursmaybeusedinthemanufactureofpuffbiscuitsthough
thetendencyistousestrongeroneswhicharesuitableforbreadmaking.
ingstages.Weakerfloursarealsolesstoleranttoprocessinterruptions.
Cheese,wheyandmilkpowdersmaybeaddedforflavourandcolourinthe
manufactureofpuffbiscuits.Cheesepowdersarehighinfatandproteinsand
tendtoreducetheliftandflakinessofthefinalproduct.Cheesepowderstendto
haveashortshelf-lifeduetotheirhighfatcontentandshouldbeusedwithcare
toavoidunwantedrancidflavoursbeingcarriedthroughtothefinalproducts.
Acommonpracticeinthemanufactureofsavourypuffbiscuitsisto
spraythesurfaceoftheproductwithoilimmediatelyafterbaking(
Manley,
2000
).Thistreatmentgivestheproductsashinysurfaceandenhancesits
colour.Sprayingmayalsobeusedtoaddflavour.However,oil-basedsprays
andflavoursaresusceptibletorancidityandsocareisrequiredintheiruse.
Reference
Manley,D.,2000.TechnologyofBiscuits,CrackersandCookies,thirded.Woodhead
PublishingLtd.,Cambridge,UK.
Biscuits,Cookies,CrackersandWafers
Chapter|6
323
6.19ISITIMPORTANTTOUSEAFERMENTATIONPERIOD
INTHEMANUFACTUREOFCRACKERS?WHATEFFECTSARE
WELIKELYTOSEEFROMVARIATIONSINTHE
FERMENTATIONTIME?
Afunctionofthefermentationtimeinthemanufactureofcrackersisthe
inparticular,toreduceitselasticityandincreaseitsextensibility,itiseasier
tomachinethedoughandtocreatetherequiredlaminatedstructurewhich
deliversaflakytextureinthefinishedproduct.Duringthefermentation
period,thereisasmallincreaseindoughacidity(lowerpH)whichnotonly
contributestotherheologicalpropertiesofthedoughbutalsopotentiallyto
bakedcrackerflavourandcolour.Duringfermentation,thereisconsiderable
enzymicactivityfromboththeflourandyeastsources.
Itisimportanttorecognisethatfermentationisnotjustamatteroftime,
butitisalsoaffectedbytemperature(fermentationincreasesastemperature
increases)andyeastlevel(higheryeastlevelsyieldgreaterfermentation).
Thus,inpractice,fermentationtimeisseldomconsideredasasingle
variable.
Longfermentationtimesleadtoconsiderablegassingactivitybythe
yeastandincreasedenzymicactivity.Thelatterwillbedominatedbythe
amylaseactivityonthedamagedstarchintheflourandbyproteolyticactiv-
ityontheflourproteins(glutenstructure)bothofwhichresultinsoftening
ofthedoughwithprolongedfermentationwhichmakesitmoredifficultto
handleandprocess.Thismayresultintheneedforincreaseddustingflour
withsomepotentiallossofcrackerlift.LowdoughpHscomingfrom
extendedfermentationtimesmayincreasethelikelihoodofcracker
shrinkage.
Themainimpactofshorteningdoughfermentationtimesisthatthe
doughwillbetougher(moreresistanttodeformation)andhardertomachine.
ofcrushinglayersandlosingcrackerliftandflakinessduetobreaksinthe
layering.
Ifyoudowanttoreducefermentationtimes,thenyoumayfindithelpful
toaddalittleextrawatertothedoughformulationtoyieldasofter,more
machinabledoughortoadddoughsofteningagentssuchas
L
-cysteine
hydrochloride(see
Section2.7.7
)orproteolyticenzymes.Youwillneedto
becautiouswhenusingdoughsofteningagentsastherecanbeaprogressive
build-upoftheirlevelsthroughthecontinueduseofreworkandeventually
thedoughmaybecometoosoftformachining.
324
BakingProblemsSolved
6.20WEHAVEINSTALLEDANEWCUTTINGAND
CREAMINGMACHINEFORTHEPREPARATIONOFOUR
SANDWICHWAFERSANDREFURBISHEDTHEPRODUCTION
Chapter|6
6.21OURCHOCOLATE-COATEDWAFERBISCUITSARE
PRONETOCRACKING.CANYOUSUGGESTWHYTHIS
HAPPENSANDHOWWECANAVOIDTHEPROBLEM?
Themostlikelycauseofyourproblemistheabsorptionofwaterbythe
waferinthecoatedbiscuitanditssubsequentexpansion.Wesuggestthat
youlookcloselyatthequalityofyourenrobingpracticesbecauseany
uncoatedareasorevenpin-prickholesinthecoatingprovideaccesspoints
forwaterfromtheatmosphere.Thelongerthattheproductsarestored,the
greaterthepotentialforthewaferbiscuittopick-upmoistureandexpand.
Themoisturecontentofwafersisverylowinorderthattheywillhavea
crispeatingquality.Theequilibriumrelativehumidityofthewaferisalso
verylowandmuchlowerthantherelativehumidityofmostatmospheric
conditionsinwhichtheproductswillbekept.Thismeansthatthenatural
drivingforceisforwaterfromtheatmospheretocondenseonexposedwafer
moisturelevelrises,thewaferwillbegintoexpandandexertsomuchpres-
sureontheinelasticchocolatecoatingthatthelatterwillsplit.
Barron(1977)
Thetimetakenforthecrackstobecomemanifestwillvaryaccordingto
relativehumidityofthesurroundingatmospherewillalsoaffecttherateof
waferexpansion,thehighertherelativehumiditythegreatertherelative
humiditydifferentialandthefasterthetransferofmoisture.Onewaytolimit
thislattereffectistoensurethatthewrappingofthefinalproductistight
aroundtheproductandsohasaminimumvolumeofairaroundtheproduct.
Unfortunately,manychocolate-coatedwaferproductsarefoilwrappedwhich
doeslittletolimittheingressofmoisture.Ultimately,thesolutiontoyour
Reference
Barron,L.F.,1977.Theexpansionofwaferanditsrelationtothecrackingofchocolateand
bakerschocolatecoatings.J.FoodTechnol.12,73

84.
326
BakingProblemsSolved
6.22WEAREEXPERIENCINGINTERMITTENTPROBLEMS
WITHGLUTENFORMATIONINOURWAFERBATTER.WHAT
CAUSESTHISPROBLEM?
Glutendevelopmentisundesirableinwaferbattersbecauseitcanleadto
blockagesinpipesornozzlesofbatterdistributionsystems.Inthelatter
case,thiscanleadtounevendistributionofbatterontheplatesandthe
practicetohavefiltersindifferentpartsofthelinetoremoveanygluten
ballswhichform.
Glutenformationdependsofthreemainfactors;thepresenceofprotein
intheflour,thehydrationofthatproteinfromtheadditionofwaterandthe
inputofenergyduringmixing.Inbattersystems,theratioofwatertoflour
solidsisusuallyhighenoughtolowerbatterviscositytosuchanextentthat
glutenformationshouldnotoccur(
CauvainandYoung,2008
).However,
waferbattersareoftenpumpedandrecirculatedthroughholdingtanksto
preventseparationofthesolidswhiletheyarestanding,andthismaycause
shearinanumberofareasofthepipework.Shearleadstoworkandsubse-
quentlyincreasedglutenformation.
Astherecirculationofwaferbattersisapracticalexpedient,thenyou
willhavetolooktochangesiningredientspecificationorbatterformulation
toalleviatetheproblem.Loweringtheoverallproteincontentoftheflour
thatisusedisamostobviouswayofreducingthepotentialforglutenforma-
tion.Thismaybeachievedbyusingweakerorsoftermillingwheats.
Alternativelyyoucouldusealowprotein,starch-richfractionfromanair-
classifiedorfractionatedflour,typically,thiswouldequatetoparticlesinthe
range15to40

m.
Alternatively,youcouldreplaceaportionofyourstandardflourwitha
heat-treatedfloursuchasmightbeusedforcakemaking.Heattreatment
denaturestheproteinandrestrictsitsglutenformingpotential(see
Section
2.2.17
)butwillaffectwaterabsorptionandanincreaseinthewateraddition
willbenecessarytomaintainastandardbatterviscosity.Otherwaysto
reduceglutenformationwouldbetoreplaceaportionofthestandardflour
withachlorinatedflour(see
Section2.2.18
)inthosepartsoftheworld
whereitsuseispermittedorwithstarchfromwheatorsomeother
suitablesource.
Beawarethatloweringtheproteincontentoftheflourusedinyourbatters
mayhaveanadverseeffectonthewaferstrength,makingthemmorefragile
andsomorepronetophysicaldamage,especiallyduringcuttingandcreaming.
Reference
Cauvain,S.P.,Young,L.S.,2008.BakeryFoodManufactureandQuality:WaterControland
Effects,seconded.Wiley-Blackwell,Oxford,UK.
Biscuits,Cookies,CrackersandWafers
Chapter|6
327
6.23WHATARESHREWSBURYBISCUITSANDHOWARE
THEYMADE?
Shrewsburybiscuitsareoneofseveralold-styleEnglishbiscuitsthatwere
traditionallymadebylocalbakersbeforetheadventoflarge-scalebiscuit
andcookiebakeries.Collectively,theywouldbereferredtoas
Confectionersbiscuitsandwouldbemadeonarelativelysmall-scale.
Manyofthedifferenttermsforsuchbiscuitshavefallenoutofuse,anda
goodnumberofConfectionersbiscuitshaveevolvedintothemainbiscuit
andcookietypesfamiliartoustoday.Manyofthetraditionalrecipesfor
Confectionersbiscuitstendtousebutterasthefatandwholeeggsasthe
moisteningagents,andmanyofthemixingprocessesaresimilartothose
usedincakemaking.
6.24WEFINDTHATOURVIENNESEFINGERSGOSOFT
VERYQUICKLYAFTERBAKING.HOWCANWEPREVENTTHIS
FROMHAPPENING?
Whenbiscuitsgosoftafterwrapping,itisusuallybecauseofmoisture
uptakeduringstorage.Whenabiscuitiswrappedinawell-sealedmoisture-
impermeablefilmsofteningdoesnotoccur.
Thereareotherpossibleexplanations.Theseincludethefollowing:
thepresenceofmoistureinthefillingwhichleadstomoistureabsorption
bythebiscuitasaresultofmoisturemovementfromthefilling;
thepresenceofinvertsugarintherecipe;
under-bakingofthebiscuitoriginallysothatmoremoistureremainsin
theproduct;
condensationontheinternalsurfaceofthepackagingfilm.
Softeningofthebiscuitcanbepreventedbytheuseofamoisture-freefill-
ingsuchasacompoundshorteningorhardenedpalmkerneloil,insteadof
margarine,whichcontainssomemoisture.Checkthattherecipedoesnotuse
invertsugarsyrup.Ensurethatthebiscuitsarewelldriedoutinbakingand
thatthebiscuitsarecooledadequatelybeforepacking.Especially,avoidtrans-
ferringproductstoacoldatmosphereafterpackingassuchchangesintemper-
aturecanresultincondensationontheinsideofthewrapper.
Biscuits,Cookies,CrackersandWafers
Chapter|6
Thispageintentionallyleftblank
Chapter7
Pastries
7.1LAMINATEDPASTRIES
7.1.1Whatcausespuffpastrytoriseduringbaking?
Mostoftheliftinpuffpastrycomesfromthewaterheldinthedoughlayers
whichwhenconvertedtosteamintheoven,becomestrappedinthemelting
Fig.7.1
).Thepressure,whichisgenerated
bythetrappedsteam,forcesthedoughlayersapart.Thethicknessofthe
doughlayerschangeslittleduringbakingandmakesnosignificantcontribu-
tiontopastrylift.
Expansionofthepastecanonlyoccurifthedoughlayersaresepa-
doughlayers,suchasmaybecausedwhenadjacentlayersarecrushed
nocrushingoccurs,thenthebakedpastrymaybesoflakythatitfalls
apartafterbaking.
Mostoftheexpansionofpuffpastryoccursinthefirsthalfofthebaking
enoughtostandwithoutcollapsing(
CauvainandYoung,2008
).
Inthecontextofcreatingliftinlaminatedproducts,thecharacteristics
ofthefat,particularlyitsmeltingprofile(see
Section2.3.1
),areveryimpor-
tant.Ifthefathasalowfinalmeltingpoint,thentheliftwillbelimited.
However,althoughahighmeltingpointmaybedesirablefromthepointof
viewoflift,theremaybeundesirableeatingqualitiesintheformofpalate
cling.Equally,thelaminatingfatmustremainplasticenoughtodeformdur-
breaksinthefatlayerswillallowthereadylossofsteamduringbakingand
limitpastrylift.
Damagetothedoughlayersduringprocessingmustalsobeavoidedto
optimiselift;breaksinthedoughla
yersprovideweakpointsthrough
whichthesteamcanreadilyescapeand
limitlift.Docking,thepracticeof
carriedoutwithcare;tooheavilyadockedproductwillloseliftthrough
331
BakingProblemsSolved.DOI:
http://dx.doi.org/10.1016/B978-0-08-100765-5.00007-2

2017ElsevierLtd.Allrightsreserved.
theescapeofsteam,whereastoo
lightlyadockedproductwillhave
unevenliftandlargeblistersmayform.
Reference
Cauvain,S.P.,Young,L.S.,2008.BakeryFoodManufacture&Quality:WaterControland
Effects,seconded.Wiley-Blackwell,Oxford,UK.
Furtherreading
Cauvain,S.P.,2001.Theproductionoflaminatedproducts.CCFRAReviewNo.25.
CampdenBRI,ChippingCampden,UK.
FIGURE7.1
Mechanismforpuffpastrylift.
332
BakingProblemsSolved
7.1.2Weareexperiencingaproblemwithourpuffpastry
whichfailstoliftandshowsnosignoflayeringonbaking.Why
isthis?
separatedlayersoffatanddough.Themechanismbywhichpuffpastryrises
reliesonthisseparationasdescribedabove(see
Section7.1.1
)andanynum-
berofingredient,recipeorprocessingchangesmaycausetheproblem.
Wesuggestthatyouexaminethefollowing:

Thesolidfatcontentofthefatthatyouareusingasfatswithlowcon-
tentsarecanresultinpoorlift.

Thenumberoflaminationswhichyouaregivingthepaste.Toomany
laminationscausethefatlayerstoruptureandallowthebrokendough

Theapplicationofanydockingmechanismsbecauseexcesspressureor
restrictexpansion.

Youroventemperature,ashighertemperaturesencouragelift.You
shouldbakeataround230

C.
Youcanincreasepastryliftbyusingastrongerflourprovidedthatsuffi-
cientrestisgiventoachievetheoptimumdoughrheologyduringprocessing
andbeforebaking.Lowlevelsofanoxidisingagent,e.g.,ascorbicacid,may
helpbutyoushouldnotethecommentsonpastryshrinkage(see
Sections
7.1.9
and
7.1.13
).
Pastries
Chapter|7
333
7.1.4Whatarethepurposesoftherestingperiodsinthe
manufactureoflaminatedproducts?
Therheologyofthebasedoughisveryimportanttotheformationofthedis-
changethedoughrheologyduetotheworkthatisimparted,especiallyby
elasticityandtoreduceitsextensibility,andthismayleadtotearingor
breakdownoftheindividualdoughlayers.Theholeswhichforminthe
bakingandthisrestrictsthepastryliftthatcanbeobtained.
Ifadoughislefttorestaftermixingorsomeotherformofwork,itsrhe-
ologicalcharacterchangeswithtime.Inparticular,itscharacterbecomes
lesssevere.Thus,akeyrolefortherestingperiodistomodifythedough
rheologysoastopreserveintacttheseparationofdoughandfatlayersso
importanttotheformationoflaminatedproductstructure.
Thedegreeofchangeindoughrheologyisinfluencedbytemperature
andvarieswithdifferentflours.Strongflours,thatisoneshighinprotein
orwithstronglyelasticglutens,requi
relongerperiodsofrelaxationthan
weakeronestoachievethenecessary
rheologicalchangesforoptimum
productquality.Thischangeinrheologicalpropertieswithrestingtime
islinkedwiththenaturalreducingagents(glutathione)andenzymic
activitiesintheflour.
Thedatain
Fig.7.2
comparetherheologyoftwoflours,onestrongand
oneweak,andexaminesthechangesindoughresistancetodeformation
whichoccurwithrestingtime.Inthecaseofthestrongerflour,someresting
timeisrequiredforthedoughtoachievetheoptimumzoneanditremains
thereforthefullrestingperiod.Theweakflourontheotherhandisimmedi-
atelyintheoptimumzonebutrapidlypassesthroughit.Theseobservations
allowustoconcludethatweakfloursaremoresuitedtorapidprocessing
Pastries
Chapter|7
335
FIGURE7.2
Effectofrelaxationtimeondoughdeformationresistancewithtwoflours.
7.1.5Wehavebeenexperiencingsomeproblemswithexcessive
shrinkingofourpuffpastryproducts.Canyouadviseastowhat
thelikelycausesmightbe?
Someshrinkageofpuffpastryduringbakingisinevitablethoughitcanbe
minimised.Itisalsoimportanttorecognisethatinmostcasespuffpastrylift
andshrinkagearelinkedwithgreaterliftoftenleadingtogreatershrinkage
andviceversa.
Causesofexcessiveshrinkagemaycomefromanumberofrecipeand
processingsources,including:

floursrequirelongerrestingperiodsthanweakfloursinorderfor
Section7.1.4
).

Oxidants,suchasascorbicacid,maybepresentintheflourordough
formulation.

ThepHofthedoughistoolowduetotheadditionofacidicmaterials
(see
Section7.1.6
).

Thesugarlevel,ifpresent,istoohigh.

Thelevelofrecycledtrimmingsinthepasteistoohigh.Thisisespe-
thaninthemixer.

Insufficientrelaxationofthepasteduringtheprocessingstageswhatever
theflourstrength.Thisoftenappliestothestageaftercuttingoutand
beforetheproductenterstheoven.
Shrinkagemaybeovercometosomedegreethroughtheadditionofa
L
-cysteinehydrochlorideora
proteolyticenzyme.However,assuchmaterialsremainrelativelyactivein
thepaste,theeffectinrecycledtrimmingsmayleadtoexcessivesoftening
ofthepaste.Werecommendthatyoutrytoreduceshrinkagebyothermeans
beforeconsideringtheadditionofsuchmaterials.
Pastries
Chapter|7
337
Theacidificationofdoughswascom
monlyseenasameanstostrengthen
theflourgluten,makingitmorepliableandextensible,which,inturn,
wouldleadtoextrapastrylift.Although
itiscertainlytruethatpuffpastry
liftisincreasedbytheadditionofasu
itablefood-gradeacid,thereisalso
atendencyforpastryshrinkagetoincrease(see
Fig.7.3
).Withhighlevels
ofacidaddition,shape-criticalprod
ucts(e.g.,vol-au-ventrings)may
expandexcessivelyandnon-uniformlyintheovenandmayeventopple
overduringbaking.
Theoptimumlevelofacidadditionvariesaccordingtothetypeof
acidandtheflourbeingused.Variationsinpastryshrinkagefromthe
additionofagivenlevelofacidtoarangeoffloursareusuallygreater
thanvariationsinpastrylift.Thereasonsforthevariationsarenot
clearbutaremostlikelytocomefromvariationsinthenaturalbuffering
effectsofdifferentflours(i.e.,variationsinpastepH)andtherheologyof
thegluten.
Wherepossible,greaterpastryliftshouldbesoughtthroughother
means(see
Section7.1.2
)ratherthanthroughtheadditionofanacidtothe
dough.
FIGURE7.3
EffectsofpHonpuffpastrylift.
338
BakingProblemsSolved
7.1.7Whatisthebestwaytoreusepuffpastrytrimmings?At
Chapter|7
Itisworthnotingthatthecontinuedre-useoftrimmingswillleadtoapro-
gressiveconcentrationofsubcomponentsinproduction,andthismayhave
unwantedeffects,e.g.,increasingconcentrationofpasterelaxantswhichmay
makethepastesticky.Thisisusuallydealtwithbyincorporatingabreak
intotheproductioncyclewhenanyunusedtrimmingsaresenttowaste.
Tousetrimmingssuccessfullywesuggestthefollowingguidelines:
Recycletrimmingsbyaddingthemtothemixerratherthantryingtoadd
7.1.8Weareexperiencingproblemwiththediscolourationof
blackspotsappearonthesurface.Canyouexplainwhythishappens
andadviseonhowtoavoidit?
Thediscolourationanddarkspotsthatyouseecomesfromenzyme-assisted
oxidationofthepolyphenolsnaturallypresentintheflour.Thesepolyphe-
nolsareassociatedwiththebranparticlesthatcomethroughfromthemill-
ingprocessforwhiteflour.Thegreaterthelevelofbranpresentintheflour,
thegreaterwillbethepotentialnumberofblackspotsandthelargerthe
branparticlesizethelargerwouldbethespot.
Althoughenzymicactivityisreducedasthestoragetemperatureis
lowered,thereisstillsufficientactivityevenatrefrigeratedtempera-
turesfortheproblemtobemanifestbecauseofthelongstoragetime
involved.Onepossiblewayinwhichtoavoidtheproblemwouldbe
tolowerthestoragetemperatureevenfurther,perhapsevenlow
enoughtofreezethepaste.However,whileusingthisapproach,you
willhavetoensurethatthepasteissufficientlydefrostedforsubse-
quentprocessing.
Othermeansofminimisingtheproblemincludethefollowing:

Excludingoxygensuchasbystoringthepasteingas-tightfilm.

Addingascorbicacid,thoughthismayadverselyaffectpastryliftand
shrinkage(see
Section7.1.5
).

Addingcitricacidatlowlevels,i.e.,upto0.2%flourweight,butthistoo
mayadverselyaffectpastryliftandshrinkage,andflavour(see
Section
7.1.6
).
Theeasiestandmostreliablesolutionistochangetoawhiteflourwitha
lowerlevelofbranpresent(e.g.,lowergradecolourfigureorlowerash,see
Section2.1.1
).
Theadditionoflowlevels(5

15ppm)ofglucoseoxidaseis
claimedtopreventtheformationofspotsandgeneraldiscolouration
offermentedandnon-fermented
doughsafterfreezingandthawing
(
Unilever,1992
).
Reference
Unilever,N.L.,1992.
Improveddoughs
,EuropeanPatentApplication0469654.
Pastries
Chapter|7
341
7.1.9Wehavebeenexperiencingconsiderablevariabilityin
wehaveproblemswithpasteshrinkageandonotheroccasions
canfindnoproblemswithingredientsadditions.Wehaveno
climatictemperaturecontrolinthefactoryoringredientstorage
facilities,aretheselikelytosignificantcontributorstothe
problems?
Producingandusingpastesatconsistenttemperaturesisveryimportantin
ensuringconsistentprocessingandoptimumfinalproductquality.Ideally,you
shouldbecontrollingingredientandenvironmenttemperaturesalongwiththe
deliveryofaconsistentpastetemperatureexmixer.Toadviseyouonthebest
waytoeliminateyourproblemweneedtoconsiderthevariousinfluences.
Ingredienttemperatures
Flourandfatarethemainingredientstoconcernus.Asyourflouris
storedinnon-insulatedsilos,youmustexpectthetemperatureofthisingredi-
enttovarywithchangesinclimaticconditions.Thecommonwayofcoping
withsuchvariationsistoadjustthetemperatureofthewateraddedtothe
mix(see
Section7.2.3
).Rememberthatwaterlevelsarelowinpastesby
comparisonwiththoseusedinbreaddough,sothecoolingpotentialofthe
recipewaterislower.Youneedtomakesurethatyouhaveanadequatesup-
plyofchilledwaterandoftenyoumayneedtoresorttotheadditionofice
oranice

watermix.Incolderperiods,youmayneedtoprovideheated
water.
Relativelyhighlevelsoffatareaddedtothebasedoughofpastrypro-
ductssovariationsinfattemperaturewillcontributetovariationsinpaste
temperature.Itisbesttokeepthefatataconstanttemperatureandonlytry
toadjustpastetemperaturesex-mixerusingwaterattheappropriatetempera-
ture.Thefunctionalpropertiesoffatsarerelatedtotheirtemperaturehisto-
ries,anditisbestnottosubjectthemtotoomanywarmandcoldcycles.
Ideally,youshouldholdyourfatatasimilartemperaturetoyourprocessing
environmentorslightlylowerthanyouridealpastetemperatureexmixer.
Ifyouareusingreworkaddedtothemixer,thenyoushouldensurethat
thisisataconstanttemperature.Ifitcomesfromachilledenvironment,then
youshouldmakesurethatthetemperaturethroughoutthebatchisuniform.
Processingtemperatures
Ideally,youshouldhaveaconstantprocessingtemperature.Thisispar-
ticularlyimportantifyouhavelongrestperiodsorareusingfatswhichare
particularlytemperaturesensitive.Youwillfindthatpastryliftisdirectly
relatedtopasteprocessingtemperatureforawiderangeoflaminatingfats
(see
Fig.7.4
).
342
BakingProblemsSolved
Inthemanufactureoflaminatedproducts,variationsinpastetemperature
candirectlyaffecttheintegrityofthelayers.Higherprocessingtemperatures
oftenresultinbreakdownofthelayeringasthelaminatingfatoils.Insuch
cases,thepastebecomesstickyandisusuallycompensatedforthroughthe
increaseduseofdustingflourontheplantorbyloweringtheaddedwater
levelbothofwhichintroduceotherproblems.
Lowpastetemperaturesmakethed
oughfirmerandmoredifficultto
0.5
1.5
2.5
3.5
ABCD
Laminating fat type
Pastry specific height (mm/g
paste)
FIGURE7.4
Effectofprocessingattemperaturesof12
Cand19
Conpuffpastrylift.
Chapter|7
7.1.10WhyshouldcroissantandDanishpastrydoughsbe
givenlesslaminationthanpuffpastry?
thepresenceofbakersyeastinthelattertwoproducts.Theyeastplaysa
significantpartintheaerationofthepasteduringproofandbakingbutalso
disruptstheintegrityofthedoughandfatlayersinthepaste.Tocounteract
ingqualityoftheproduct,itisnecessarytokeepthedoughandfatlayers
thickerthanwouldbenormalwithpuffpastry.Optimumlaminationforpuff
workinthedoughduringproof.Higheryeastlevelsandlongerprooftimes
arelikelytocausegreaterrupturing.Itisimportanttoensurethatthegluten
willlackvolumeanddefinition.Thismayrequireanincreaseinthestrength
oftheflourused.
Furtherreading
Cauvain,S.P.,2015.TechnologyofBreadmaking,thirded.SpringerPublishingInternational
AG,Switzerland.
344
BakingProblemsSolved
7.1.11Whatistheoptimumleveloffattouseinthe
productionofpuffpastry?
Theleveloffatthatisusedinthema
nufactureofpuffpastrydependsona
numberfactorsincludingthedegree
ofliftandflakinessofeatthatyou
areseekinginthebakedproduct.Puffpastryandotherlaminatedproducts
arecharacterisedbytheformationof
whichiscoveredwithfatandsubjectedtoaseriesoffoldingandfurther
offatanddough.
Traditionally,therearethreetypesofpuffpastrycharacterisedbythe
leveloflaminatingfatusedintheformulation.Theyarecommonlydesig-
natedas
full
,
three-quarter
and
half
puffinwhichthelaminatingfatisused
atanequalweighttotheflour,3/4and1/2,respectively.Theleveloflami-
natingfathasadirecteffectonthethicknessofthefatlayerinthelaminated
pasteandthusadirectimpactofthedegreeofseparationofthedough
layers.Thehighertheleveloflaminatingfat,thegreaterthepastryliftbut
alsothegreaterthepastryshrinkage.Withanincreaseinlaminatingfat
levels,thebakedpastriesbecomemoretendereating.
Thereisnoabsoluteoptimumleveloffatforuseinthemanufactureof
puffpastry,thechoicedependsonanumberofdifferentcriteriawhichmaybe
requiredinthefinalproduct,suchaslift,eatingqualityandflavour.Thelevel
oflaminatingfatisalsolinkedwiththenumberoflaminations(foldsorturns)
giventothepaste.Ingeneral,thelowerthelaminatingfatlevelthelowerwill
bethenumberoflaminationsrequiredtoachievemaximumliftoroptimum
quality;typically,theoptimumqualitywithhalfpasteisachievedwith128the-
oreticalfatlayerswhilewithfullpastetheoptimumwasachievedwith256.
Thebasedoughmayalsohaveasmalladditionoffat(5%)whichconfers
amoretendereatingqualitytothebakedproductbutdoesdecreasepastry
lift.Duetothelattereffect,werecommendthatyouavoidusinglevelsof
addeddoughfatgreaterthan10%oftheflourweight.
Similareffectsofchangingfatlevelsmaybeobservedintheproduction
ofDanishpastryandcroissantthoughthenumbersoflaminationsarefewer
thanwithpuffpastry,andthemaximumlaminatingfatlevelliesaround
65%oftheflourweight.
Furtherreading
Cauvain,S.P.,2001.Theproductionoflaminatedproducts.CCFRAReviewNo.25.
CampdenBRI,ChippingCampden,UK.
Pastries
Chapter|7
345
7.1.12Wewouldliketoreducetheleveloffatthatweuseto
provideuswithsomeguidanceastohowwemightachieveour
objectives?
Asyouknow,thelaminatingfatplaysamajorroleindeliveringliftin
puffpastryandotherlaminatedproducts.Assoonasyoureducethe
ratiooflaminatingfattobasedough,youwillexperiencesomelossof
lift.However,thereissomepotentialformakingotherchangestoyour
recipeandprocesswhichmaybeofhelp.Youhavenotprovidedany
generalguidance.
Thefirstpointtomakeisthatthepotentialforreducingfatlevels
dependsontheratiooffattobasedoughandthenumberoflaminationsthat
youaregivingthepasteduringprocessing.Thegeneralpatternisthatfor
anyratiooflaminatingfattobasepastryliftincreasestoreachamaximum
beforefallingasthenumberoflaminationsincreases.Thelossofliftcomes
fromthecrushingandlossofintegrityofthedoughlayersinthepaste.
Dependingontheratiooflaminatingfattobasedoughandthenumberof
laminationsthatyouaregivingthen,itmaybepossibletouselesswith
fewerlaminationstomaintainpastrylift.
Youcouldinvestigateusingastrongerflourtomaintaintheintegrityof
thedoughlayers,butifyoudothenyoumayneedtolengthentheresting
timesthatyouareusingduringprocessing.Thismaybedifficultonaplant
withafixedthroughput.Withstrongerflours,youmayfindthatincreasing
themixingtimehassomepositivebenefitonpastrylift.Thisisakintousing
moreenergyonthemixingofbreaddough.Commonly,pastrydoughisless
developedthanbreaddoughbutextendingthemixingtimewellbeyondthat
normallyconsideredappropriate,e.g.,from2to5andeven10minutes,can
timetosuchanextent,thenyoumayneedtousecrushedicetohelpyou
controlthefinalbasedoughtemperature.
Asnotedin
Section7.1.9
,youmayfindthatyoucanadjusttheproces-
singtemperaturetoalowervalueands
tillmaintainlift.Anypotentialben-
efitfromthistypeofchangewillbe
influencedbythetypeoflaminating
fatthatyouareusing;forexample,see
Fig.7.7
whichillustra
testheeffect
ofprocessingtemperaturewhenusi
ngbutter.Loweringtheprocessing
temperatureincreasesdoughresista
ncetodeformationandsoagainyou
mayneedtoadjustpasterestingtimestoavoidproblemswithproduct
shaping.
Theadditionoftrimmingstendstoredu
cepastrylift,especiallyifthey
arebeingfolded-intothepastedurin
gsheeting.Therearetwooptions,you
couldreducetheoverallleveloft
rimmingsthatyouaddoryoucould
346
BakingProblemsSolved
changetomixingthetrimmingsintothebasedough.Addingthetrim-
mingsatthemixerroughlyreducestheirnegativeimpactonpastryliftby
about50%.
Anumberoffatreductionandfatreplacementtechnologieshavebeen
summarisedby
.
Reference
Wickramarachchi,K.S.,Sissons,M.J.,Cauvain,S.P.,2015.Puffpastrytrendsinfatreduction:
anupdate.Int.J.FoodSci.Technol.50,1065

1075.
Pastries
Chapter|7
347
7.1.13Weareexperiencingdistortionofourpastryshapes.We
havemeasuredtheshrinkagebutfindthatitisnoteven.We
havealsonoticedthatthelaminatedproductsareexperiencing
somevariationinproductlift.Whatmightbethecausesofthese
problems?
Therearequiteafewcausesofpastryshrinkage(see
Section7.1.5
)which
includeusingaflourwhichhastoohighaproteincontentandover-mixing
thepastewhichyieldsexcessiveglutenformationinthepasteorbasedough
forlaminatedpastries.Oftenpasteshrinkagecanbeminimisedbymaking
restingperiodslonger(see
Section7.1.4
).Ifthisisnotpossibleonan
automaticproductionline,youcanconsideraddingapasterelaxantsuchas
L
-cysteinehydrochloride.
Youdescribetheproblemasbeingunevenshrinkagewhichsuggests
thatitisnotaningredientormixingproblembutmorelikelytobe
relatedtopasteprocessing.Checkth
atrestingtimesarebeingcontrolled
andthatyouarenotexperiencingun
dueproductionstoppages.Ifsuch
issuesarenotthecauseoftheunevennessinproductshrinkage,thenyou
Youshouldexaminethewaythatyouareusingpastetrimmings.Ifyou
backatthemixingstage,thentheyshouldberecycledatregulartimeinter-
valsandinregularproportionstoyourvirginpaste,andideally,theyshould
beataconsistenttemperature.
pasteelasticitycancausedistortedshrinkageespeciallywithroundorcom-
plexshapes.Themostcommonwayofreducingthisproblemistoemploya
cross-pinningroller;thisisasmallwheelwhichmovesrapidlybackwards
makesurethatitisdoingitscorrectjob,ifyoudonothaveonethenyou
maywanttofitone.
Theprocessoflaminatingpastewillevenoutsomethestressesreferred
toabovethoughemployingacross-pinnerbeforecuttingtheshapesisstilla
goodidea.However,thereisamorefundamentalprocessingproblemfor
youtoconsider,namelythatafterthepastehasbeenfoldedandisthen
Fig.7.5
).Thisoccursinmanyplantsduetothecharacteristiclapping
motionwhilethepasteisstillmovingdowntheplant.Thespreadofthew
348
BakingProblemsSolved
dependsonthenumberoflaminationsthatyouaregivingthepastewith
respecttothespeedoftheplant.
Atedgesofthelaminatedpaste,the
recanbetendencyforthelaminat-
ingfattobeexpressedfromwithinthelayerswhentheyaresheeted,andif
morelaminationsarecarriedout,itbec
omesredistribute
dinthesubsequent
layering.Thus,insomepartsofthepas
inthedoughtofatratios,andthiscontributestovariationsinliftand
shrinkage.Theextentofthevariatio
ncanbeassessedbysamplingproducts
Fig.7.5
).
Toreducethevariation,youwillneedtoreducethelengthofeachwso
thattheyspreadoverashorterdistance,andthisusuallyrequirestheplant
speedtobesloweddown;suchachangemaynotbepossibleasitwill
reducetheplantthroughput.Alternatively,youmayfindthatachangeinthe
numberoflaminationsthatyougivethepastewillreducethedegreeof
variabilitythatyouareexperiencing.Commonly,liftandshrinkagegohand-
in-handsothatareductioninthenumberoflayersmaygiveyoulessshrink-
age;youwillneedtocarryoutsometrialstoseeifthelossofliftis
acceptabletoyou.
Direction of
travel on
plant
Direction of
pastry lapping
travel on plant
FIGURE7.5
Typicalprocessingpatternonlaminatedpastes.
Pastries
Chapter|7
349
7.1.14Wearelookingtostartproductionofcroissant.
Inmytravels,Ihaveseenmanyvariationsonproductswhich
arecalledcroissant.Whyaretheresomanydifferentforms
andhowaretheymade?
Anessentialfeatureoftheproductst
hatwecallcroissantisthattheyare
madefromalaminateddough,thatis,onewhichcomprisesalternate
layersofafermenteddoughandasuitablefat.Mostpeopleconsider
theoriginsoftheproducttobeincentralEuropeandanumberof
legendssuggestthatareassociate

Pasteprocessingtemperature.

Thetrianglesizeoftheunitcroissant.

Recyclingpastetrimmings.

Proverconditions.
Therearealsosomesignificantinteractionswhichneedtobeconsidered
inthesuccessfulmanufactureofcroissant.
Thequalitycharacteristicsoftheflour
Ingeneral,strongfloursareneededforcroissantproduction,butitis
importanttoformanextensiblenotelasticglutentoavoidproblemsduring
andlaminatingstages.
Themixingofthebasedough
Thecommonpracticeistounder-developthebasedoughbycompari-
sonwithbreadproduction.Thisissaidtoallowfortheextradevelopment
However,itistherheologicalcharacterofthebasedoughleavingthemixer
Under-developmentduringmixingdoesnotautomaticallydelivertheappro-
priatedoughrheology.
Thequalitycharacteristicsofthelaminatingfat
Thelaminatingfatwillbeextrudedontothebasedoughbeforetheinitial
sibletohelpwithliftinbaking(see
Section2.3.1
).Butterisapopularfat
usedinthemanufactureofcroissantbutitsmeltingpointislow,andthis
makesitdifficulttousewithoutrefrigerationofthepasteduringproduction
(see
Section7.1.12
).
Yeastlevelinthebasedough
Thelevelofyeastinthebasedoughwilldependonanumberofotherrecipe
andprocessfactors,e.g.,processingandfinalprooftemperatures.Theproduc-
tionofcarbondioxidegasbytheyeastinthebasedoughwilldisruptthelayered
structureoftheproduct,especiallyduringproof,andthiscanreducelift.
Theratiooflaminatingfattobasedough
Inthemanufactureofcroissant,theratiooflaminatingfattobasedough
haslessimpactonpastryliftthanwouldbethecasewithpuffpastry.Thisis
becauseofthedisruptingeffectoftheyeastactivity.Theleveloflaminating
fatwillhaveasignificanteffectontheeatingqualityoftheproductandits
flavour,especiallyifbutterisusedasthelaminatingfat.
Pastries
Chapter|7
351
Thenumbersoffatlayerscreatedduringlamination
Asageneralrulerelativelyfewfatlayersarecreatedincroissant,typi-
cally18

32(see
Section7.1.10
).Thisisincontrasttopuffpastryproduc-
tionwherethenumberswillbetwoorthreetimesgreater.Onceagain,itis
thedisruptingeffectoftheyeastactivitythathastobetakenintoaccountso
theaimistotryandkeepthefatanddoughlayersintacttogainliftandcon-
tributetotheflakyeatingcharacterofthefinalproduct.
Akeyaimduringsheetingistoavoidbreakingupthefatlayersinthepaste
asthiswillallowthereadyescapeofsteamfromthebasedoughandrestrictlift
intheoven.Therollgapsettingswhichareusedarestronglyinfluencedbythe
rheologicalcharacterofthebasedoughandtheneedtoachieveaparticular
widthreadyforthelaminating(folding)stagewhichfollowssheeting.
Restingperiodsarehelpfulinadjustingtherheologicalcharacterofthe
longerprocessingtimespermitgreateryeastactivityandsoabalancemust
Pasteprocessingtemperature
integrityofthefatlayers;toolowandthefatwillbebrittle,toohighandthe
fatwillreadilyturntooil.Lowerprocessingtemperatureshelplimityeast
activitybeforefinalproof.
Thetrianglesizeoftheunitcroissant
appearanceofthecroissant.Wesuggestthatyoutryrollingafewdifferent
shapedtrianglesandseewhichoneyouprefer.
Recyclingpastetrimmings
Therewillalwaysbesometrimmi
production.Youcanre-usethesebyaddingthemtothemixer,butyou
mustcontroltheirlevelandageinordernottointroduceunwantedproduct
variation(see
Section7.1.7
).
Proverconditions
Yourchosenprooftemperatureshouldbelowerthanusedwithbreadto
avoidoilingofthefatandlossoflift.Provertemperaturesintherange
30

32

Careusuallysuitablewithahumidityof70

80%.
352
BakingProblemsSolved
7.1.15Wewishtomakecroissantwiththemouldedends
joiningtoformacirclebutfindthattheyopenupduringbaking.
Canyousuggesthowwecanovercomethisproblem?
workthatisdoneonthelaminateddough;ittendstobecomemoreelastic
andlessextensibleincharacter.Therelaxationperiodswhichcommonlyfol-
elasticandmoreextensible.Inasimpleshape,suchasavol-au-ventringor
asquare,theelasticcomponentofpasterheologymanifestsitselfasan
eccentricityofshape,i.e.,onesideorradiusshrinksmorethantheother.
Thusitisnotuncommonforaroundvol-au-ventringtobecomeovalora
squareshapetobecomerectangular.
Inmorecomplicatedshapes,suchascroissant,otherschangesmaybe
observedwhenthedoughistooelasticandthesemayincludetheopening-
outofthecircularshape.Increasedpasteelasticitymaybeovercomeina
numberofdifferentwaysincludingthefollowing:

Higherwaterlevelsinthebasedough.

Aweakerflour.

floursareused.

Asuitablerestingperiodaftertheformationofthecircleandbeforethe
croissantenterstheoven.Thisusuallyoccursintheprover.
Thecomplicatedshapeofacroissantandthemannerinwhichitiscut
Towardstheendofprocessing,muchoftherolleractiononthepasteisin
onedirection,thatis,inthedirectionoftravelontheplant.Thetriangular
shapewhichisrequiredforcroissantbeforeitisrolledupmaybecuteither
inthedirectionoftraveloratrightanglestoit(see
Fig.7.6
).Inthelatter
case,thestresseswithinthecurledpiececanoftenleadtotheproblemyou
describe.Ifyoucannotchangethedirectionofthecut,werecommendthat
youemployacross-piningroller,thatis,onewhichmovesarerightangles
tothetraveloftheplanttoevenoutthestresses.
Pastries
Chapter|7
353
FIGURE7.6
Effectofdirectionofcuttingoncroissantquality.
BakingProblemsSolved
7.1.16Wehavebeentryingtofreezefullyprovedcroissantfor
laterbake-off.Canyouidentifytheimportantcriteriafortheir
successfulproduction?
Thereissignificantinterestinfreezingfermentedandproveddoughpieces
withtheintentionthatthepiecesareremovedfromthefreezerandtrans-
ferredstraighttotheovenforbaking.Thiswouldmaketheproductvery
convenienttouseinarangeofbake-offenvironments.However,thereare
somesignificanttechnicalchallengestoovercome.
Asiswell-known,yeastcellsdieduringfreezingandsubsequentstorage.
Thismeansthatwhenthedoughpiecesareremovedfromtheoventhereis
nofurtherpotentialcarbondioxidegasproductionfromtheyeast.Inaddi-
tion,duringstorage,thecarbondioxidegasthathasalreadybeenevolvedin
theproofphasegraduallyleaksoutofthedough.Intheprover,thecarbon
dioxidegasdiffusesintothenitrogengasbubblestrappedinthedough,but
duringfreezingandstorage,thediffusionprocessisreversed,andinsome
cases,thisleadstocollapseofthedoughstructure.
Thefreezingofprovedlaminatedpastriesismoresuccessfulthanthat
achievedwithbreaddoughs.Thisisbecausethemechanismbywhichcrois-
santandDanishdoughsexpanddoesnotrelyexclusivelyonthereleaseof
carbondioxidegasbutismorecloselyrelatedtothepressureofsteamgener-
Chapter|7
7.1.17Wearemakingpuffpastry,Danishpastriesandcroissant
usingallbutterandoftenhaveproblemswiththeprocessing
fromthefinalproducts.Whatarethebestprocessingtemperatures
andconditionswhenusingbutterwithsuchproducts?
apopularfattouseinpastrymaking.Themeltingprofileofbuttermakesit
aparticularlypleasingfatforincorporatingintopastryproducts,butunfortu-
nately,itisnottheeasiestoffatstouseinprocessing.
Butterhasarelativelylowmeltingpoint(see
Section2.3.7
)anda
tendencytooilduringp
ing.Toovercomethisparticularproblem,youwillneedtoensurethatthe
doughtemperatureaftermixingandthe
pasteprocessingtemperaturesare
keptaslowaspossible.Thismaymea
nyouwillhavetoair-conditionthe
pastryprocessingarea.Thedataillustratedin
Fig.7.7
showhowimpor-
tanttheeffectofpaste
processingtemperaturecanbeontheliftofall-
butterpastries.Itisequallyimportan
tthattheprocessingtemperatureis
nottoolowbecausebutterlacksplasticityatlowertemperaturesandthe
integrityofthelayeringinthepastry
willbelostwithsubsequentlossof
lift.
Thelowmeltingpointofbutteralsocreatesproblemsforproving
Danishpastriesandcroissantsoyouwillfinditanadvantagetorestrictthe
temperatureinthefinalprovertoaround30

Cwitharelativehumidityof
60

75%.Theseconditionswillhelpavoidflowandlossofboldnessand
shape.
0
0.5
1
1.5
2
2.5
3
2
1
Pastry specific height
(mm/g paste)
FIGURE7.7
Effectofprocessingattemperaturesof19

Cand12

Conpuffpastryliftwhen
usingbutter.
356
BakingProblemsSolved
7.2SHORTCRUSTPASTRY
7.2.1Whatcharacteristicsshouldwespecifyfortheflourthat
unbakedchilledandfrozenshellsandscratch-bakedproducts?
Usually,thespecificationforshortpastryfloursisnotverycomprehensive
becausethereisnoneedforsignificantglutenformationinthepasteand
recipewaterlevelsaremuchlowerthanwouldbeusedinbreadmakingand
themanufactureoflaminatedproducts.Thegeneralviewisthatsoftwheat
flourswithamoisturecontentofaround14%andaproteincontentof
8

products.
ItisprobablyadvisabletoavoidflourswithlowFallingNumbers
sincetheyarehighincereal
alpha
-amylase.Thisisbecauseitiscommon
practicetorecyclepastetrimmingsinproductandthetrimmingsmaybe
storedforsometimebeforebeingused.Duringthestorageperiod,the
alpha
-amylasewillactonthestarchintheflourcausingthepasteto
softenandbecomesticky.Thismaylatercauseproblemsduringpaste
processing.
Wenotethatyouaremakingunbakedpasteproductswhichyousub-
sequentlychillorfreezeforaperiod
beforetheyarebaked.Becauseyou
aremakingsuchproducts,youshouldspecifythattheflourhasalowash
(see
Section2.2.1
)orgradecolourfigure(see
Section2.2.2
).Theneed
foranashspecificationisnotrelatedtothecolourofthebakedpastries
buttothepotentialforenzyme-assistedoxidationofthepolyphenolsnat-
urallyoccurringinwheatbran(see
Section7.1.8
).Duringrefrigerated
storage,theoxidationreactioncan
causethebranparticlestobecome
darkbrownorblackincolour.Thelargerthesizeofthebranparticles,
themoreevidentthedarkspotswillappear.Ifthebranisfinelydivided,
thenthepastemayassumeagrey,almostdirtyappearance.Theoxida-
tionreactionwillcontinueaslongasth
eproductsareheldinrefrigerated
storage.
canalsobeaproblemwithpuffpastryst
oredunderrefrigeratedconditions
(see
Sections7.1.8
and
7.2.7
).
Pastries
Chapter|7
357
Theuseofhotorboilingwaterintheproductionofthesavourypasteis
knowntoincreasethecrispnessofresultingpasteduringstorage,see
Fig.7.8
.Thereasonswhythisshouldbearenotentirelyclear.Addingthe
boilingwatertotheflourmaycauselimitedgelatinisationofthestarch
whichispresent,butthereisnodirectevidencethatthiscontributestothe
formationofacrisperpaste.Thehightemperaturemayinhibittheactivityof
theamylasesintheflourandreduceanypotentialeffectonthegelatinising
starch.Asmanysavourypiepasteswillstandforaperiodoftimeaftermix-
ingorblocking,thelimitationofanyenzymicactivitymaybevery
important.
Thehightemperatureresultingfromtheadditionofthehotwaterwill
meltthesolidfatinthemix.Thismayaiditsdispersionintothemicroscopic
voidswhicharecreatedduringmixing.Thesevoidscarrythroughtothe
bakedproductandprovidearouteforwatertomovethroughasitmigrates
fromthefillingtothesurroundingpastry.Ifthevoidsarefilledwithfat,
thenthereislessopportunityforthemovementofwaterasshownbythe
observationthatthebasepasteofpiesdoesnotsoftenduringstorage(see
Section7.2.10
).
toproduceasoftandstickypastewhichwillbedifficulttoblockbecause
thedissolvedsugarsformasyrupinthepaste.
FIGURE7.8
crispnessduringstorage.
358
BakingProblemsSolved
Totalmassingredients
requiredpastetemperature
temperaturerise
Heatinputfromflourandfat
Massofwater
Therewillbesmallerrorsinthelastcalculationbecausethespecificheat
capacitiesoftheingredientsusedarenottakenintoaccount,butasthevaria-
tionsiningredientmasseswillbeverysmallforagivenrecipe,thecalcula-
Chapter|7
7.2.4Wearemanufacturingsavouryshortpastryproducts
forming(blocking)ofthepastryshape.Therestingperiodmayapplytothe
7.2.5Fromtimetotime,weexperienceproblems
failstoremaincohesive.Canyousuggestwhythishappens?
Significantglutenformationinshortpastrydoughsisnotnormallyconsid-
wereevolvedtotryandminimisethepotentialforglutenformationby
waterproofingtheflourproteinswithfat.Althoughthedegreeofgluten
formationrequiredinthemanufactureofshortpastryisconsiderablyless
thanisrequiredinbreadmaking,someisdesirablesothatthepasteunitsor
cracksmayformonthesurfaceofthepaste.Inextremecases,thecrackmay
Toomuchglutenformationinshortpastrycommonlyleadstoproblems

lackofcohesion

and
toomuch

excessiveshrinkage

requirescarefulcontrolofrecipeand
mixingconditions.
Asmightbeexpected,thelevelofwaterusedintherecipeplaysamajor
Cauvainand
Young,2008
muchandthepastewillbetoosofttoprocess.Thefinalpasterheologyis
alsoaffectedbytheaddedfatlevelandtoadegreefatandwaterareinter-
changeableintheireffectonpastefirmness,morefatgivesasofterpaste
ingglutenformationandwaterpromotingit.Inadditiontoingredienteffects,
thefinalrheologyisalsostronglyinfluencedbythepastetemperature;with
highertemperaturesyieldingsofterandmoreeasilymachinedpastes.Itis
importanttoworktoaconsistentfinalpastetemperature.
Thecrackingofshortpastryismoreinfluencedbythelengthofthemix-
mixertendtobemorefriableandpronetocrackingbecauseoftheshort
mixingtimesemployed.Wesuggestthatyoufirstinvestigatetheeffectsof
increasingmixingtime.Youmaynoticeasmallincreaseinpastetempera-
turewhichcanbereadilycompensatedforloweringthewatertemperature.
Ifyoustillhavetheproblemwhenyouhaveoptimisedmixingtime,thenwe
suggestyoutryraisingtheaddedwaterlevel.
Reference
Cauvain,S.P.,Young,L.S.,2008.BakeryFoodManufacture&Quality:WaterControland
Effects,seconded.Wiley-Blackwell,Oxford,UK.
Pastries
Chapter|7
361
7.2.6Weareproducingunbakedmeatpiesbutfindthatthe
shortpastrylidcracksonfreezing.Thecracksbecomelarger
whentheproductthawsoutandduringbakingthefillingmay
boiloutleavinganunsightlyblemishonthesurface.
Whyisthisandwhatcanwedoaboutit?
Inthefreezer,thefatintheunbakedpastrycontractsbyabout10%invol-
ume,whereastheaqueousphaseinthepasteexpandsbyaboutthesame
amount.Thisdifferentialinexpansioncausesstressestobuild-upinthepaste
whichmayexploitanymicroscopicweaknessesthatarepresentturningthem
intovisiblecracks.Themovementofairacrosstheunbakedproductduring
thefreezingoperationremovesasmallamountofmoisturefromthesurface
untiliceisformed.Thisdryingoutofthepastealsoexacerbatestheproblem.
Thelevelofglutenformationinshortpastryisrelativelymodestcom-
paredwiththatdevelopedinpuffpasteorbreaddoughs.Thismeansthatthe
7.2.7Someoftheshortpastrycasesthatwemakefor
mouldyonthebase.Weweresurprisedaswethoughtthatthe
wateractivityoftheshellswastoolowtosupportmouldgrowth,
andwhenweexaminedthebottomofthepastries,wecansee
thatthereisadiscolourationbutwedonotthinkthatitis
mould.Canyouidentifywhathascausedthediscolouration
andhowtoeliminateit?
Wecanconfirmthattheproblemisnotrelatedtomouldgrowtheventhough
thediscolourationhasasimilarappearancetomouldcolonies(see
Fig.7.9
).
pastrybaseandthepansinwhichtheyareheldbeforebaking.Thepaste
sourceofirontoformironcompounds(similartorust)whichturndark
whenthepastryisbaked-off.
Youarestoringtheunbakedpastrypiecesinarefrigeratorovernight
beforetheyarebakedandsuchdiscolorationsaresometimesseenwith
Section4.2.13
).Itisalittlesurprisingthatyou
havehadthisproblemasthemoisturecontentofthepastrybasewillbe
somewhatlowerthanthatofdoughbutitmaythattherewassomecondensa-
tiononthepastrybaseswhentheyweretransferredtorefrigeratedstorage
andthismayhaveencouragedthereaction.
Themostobviouscourseofactionwouldbetomakeandbakethepastry
baseswithoutrefrigeratingthem.Ifthisisnotpossible,youshouldlookat
theconditionofyourpansanddiscardanywhicharescratchedordamaged.
Alternatively,youcouldblockthepastriesintofoilcaseswhichareplaced
inthepans.
FIGURE7.9
Darkmarksonthebaseofrefrigeratedpastryshells.
Pastries
Chapter|7
363
7.2.8Wearehavingproblemswiththecustardtartsthatwe
make.Thepastryshellisverypalecoloured,butifweincrease
thebakingtime,wefindthatthecustardfillingisnotvery
stableandshrinksawayfromthecaseduringstorage.Ifweraise
thebakingtemperature,thecustardfillingboilsandbreaks
Toomuchheatinputduringbakingincreasesthelossofwaterfromthecus-
tardcausingittoshrinkawayfromthepastrycaseandcrack.Duringstor-
age,thelowwateractivityoftheegggelallowsmorewatertoescapeandit
willcontinuetoshrinkand,asillustratedin
Fig.7.10
,cracksmayappearon
thesurface.Itisalwaysdifficulttofindthebestcompriseofbakingtime
andtemperatureinthemanufactureeggcustardstoyieldtherequiredpastry
colourwithoutcompromisingthefillingqualities.Ratherthantryingtocol-
ouryourpastrybychangingbakingconditionsyoucouldsubstituteaportion
ofthesucroseinthepasterecipewithdextrose;thisisareducingsugarand
willcolourmorereadilythansucrose.Ifyouhavenodextrosethenyoucan
useaglucosesyrup,rememberingtomakeallowanceforthewaterinthe
(weightforweight),butasyouareonlyreplacingaportionofthesucrose,
youmaynotnoticethedifferenceinflavour.
Theformationofastablegelinthefillingofbakedcustardsdependson
achievingthecorrectconditionsduringbaking.Itisimportanttopreventthe
temperatureofthefillinggoingtoohigh.Thestabilityofthegeldependson
theabilityoftheeggproteins(thealbumen),andanystarchesorstabilisers
presentintheformulationtoholdthewaterwithintheirstructures.Your
samplesarejustbeginningtoshowabreakdownofthegelwhichisoften
referredtoas
synerisis
(see
Section11.1
).
Undertheinfluenceofsufficienthea
t,theeggproteinswillcoagulate,
andindoingso,theirspatialconf
igurationchangesinawaywhich
reducestheirabilitytoholdlargequantitiesofwaterwithinthethree-
FIGURE7.10
Cracksonthesurfaceofcustardtarts.
364
BakingProblemsSolved
dimensionalproteinstructureformedd
uringmixing.Asthiswaterislost
fromthecoagulatedproteinstructure,itneedstobetakenupbythe
othercustardcomponentsotherwiseitwillbereleasedfromthegel.The
quantityofthereleasedwaterwhichwillbemoppedupbytheothercom-
ponentswillbelimited.
Mostcommonly,thisproblemarisesfrombakingtheproductfortoo
long.Thelongbakingtimeallowsagreaterinputofheatintothefillingand
raisesitstemperaturefarhigherthanthatofthecoagulationtemperatureof
thealbumen.Youshouldreducethebakingtime.Youmayhavetoraisethe
bakingtemperaturetoensurethatpasteisfullybaked.Raisingthebaking
temperaturewillhavelesseffectonraisingthefillingtemperaturethan
prolongingthebakingtime.
Acommonsignthatthefillingisboilingisthatthetopofthecustard
willberoundedintheoven.Ifadjustingthebakingconditionsdoesnotcure
thispartofyourproblemthenyouwillhavetoconsiderraisingtheeggor
stabiliserlevelinthefillingformulation.
Chapter|7
7.2.9Wehavebeenreceivingcomplaintsfromcustomers
thatthatourshortpastrywhichweuseformeatpieproducts
hasanunpleasanteatingcharacterwhichtheydescribe
aswaxy.Thecommentsaremostoftenrelatedtothebase
pastryinthepies.Whyisthis?
Thesensorycharacteristicthatyoudescribeisdirectlyrelatedtothetype
andpropertiesofthefatthatyouareusing.Thecrispnessofthepiepaste
indeliveringaproductwhichconsumersconsidertobeappropriate

soft
andsoggypastryismostoftenassociatedwithstalinginpastryterms.
Allbakeryfatsareamixtureofoilandsolidfatfractions(see
Section
2.3.1
).Inpastrymaking,oneofthewaysinwhichpiepastrycrispnessis
maintainedisbyusingafatwithahighmeltingpointfraction.However,if
themeltingpointofthefatisabovethatofthetemperatureinthehuman
mouth,thenitdoesnotmeltinthemouthandleavesbehindawaxysensa-
tionwhichismostoftenreferredtoaspalatecling.Theproblemisalso
linkedwiththeproportionofthefatcomponentwiththehighmeltingpoint,
thegreatertheproportionofthehighmeltingfatfractionthegreaterthesen-
sationofpalatecling.Thisparticularproblemisoftenseenwithanimalfats
whicharemorepopularinmeatpieproductionduetotheircontributionto
productflavourandwithhydrogenatedfats.
Whentheunbakedproductenterstheoven,thefatcomponentbeginsto
meltandbecomesoil.Ultimately,allofthesolidfatfractionswillbecome
liquid.Undertheinfluenceofgravity,someoftheliquidfatdrainsintothe
basepastryandfillsupthesmallvoidsthatarepresentinthepastefrom
mixingandprocessing.Inadditiontofatfromwithinthepaste,therewillbe
asignificantcontributionfromthefatinthemeatfillingsthatyouareusing.
Asthefatcomesfromananimalsource,thenitwillhaveahighmelting
point.Thecombinationofthetwodrainageprocessesincreasesthepropor-
tionoffatwhichispresentinthebasepasteandsomakestheproblemsof
palateclingmorenoticeableinthatareaofthepie.
Asyouareunlikelytobeabletomakeasuitablemeatfillingwithalow
meltingpointfat,wesuggestthatyouchangetoalowermeltingpointfatin
thepreparationofyourshortpastewhichshouldhelpreducetheproblem.
366
BakingProblemsSolved
7.2.10Whydoesourporkpiepastrygosoftduringstorage
andwhatcanwedotomakeourpastrycrisper?
Thesofteningofporkpiepastry(andthepastryofmanyothercompositepro-
ducts)arisesbecauseofthemigrationofwaterfromthemoistfillingtothe
drypastry.Thedrivingforceforthismigrationisthedifferenceinthecom-
ponentwateractivities.
CauvainandYoung(2008)
givetypicalwateractivi-
tiesforsavourypiecomponentsaspastry0.24,jelly0.99andfilling0.98.
ponentsinsavourypiesandtherateatwhichthepastrysoftensincludethe
following:

Thestoragetemperature;thelowerthetemperaturetheslowertherateof
moisturemigration.

greaterthedifferencethefastertheinitialrateofmoisturemigration.
Fatalsomigratesduringthemanufactureofpiesbutmostofthisoccurs
intheovenwhentheallofthesolidfathasturnedtooilandistherefore
mobile(see
Sections2.3.1
and
2.3.2
).Atambientorlowertemperatures,the
solidcomponentofthefatcannotmovewithinthepastrymatrix.Inthepast,
partofthesofteningofpiepastryhasbeenattributedtofatmigration,butif
thisoccurs,itisaminorcontributortopastrysoftening.Infact,themigra-
tionofoilintothebasepastryundertheinfluenceofgravityintheoven
probablycontributestokeepingthebasepastryfromsoftening.Theoilfills
manyofthemicroscopicvoidsformedinmanufactureinthebasepasteand
probablyactsasawaterproofingagentsopreventingtheingressofsignifi-
cantquantitiesofwater.
Asdiscussedabove,themaincauseoflackofpastrycrispnessisassoci-
atedwiththemovementofwaterfromthemoistfillingtothedrierpastry.
Themostcommonwaytoreducethisproblemistomanipulatecomponent
wateractivitiestoreducethewateractivitydifferential.However,inthecase
ofsavourypastry,reformulationoffillingandpastrytendstobealimited
optionastheycansignificantlyaffectkeyproductcharacteristicssoother
meansofmaintainingpastrycrispnessmustbesought.
Onewayofachievingacrisperpastryduringitsstoragelifeistoincrease
theinitialcrispnessofthepastryondayofmanufacturesothateventhough
theproductwillsoftenatthesameratethecrispnessatanygivenstoragetime
willbegreaterthanthestandard.
Insummary,theopportunitiesforimprovingpastrycrispnessare:

Lowerthetemperaturetoslowdowntherateofmoisturemigration.

Reducetheabsolutedifferenceinwateractivitiesbetweenthecomponents.

Pastries
Chapter|7
367

Increasetheproteincontentoftheflourusedinthemanufactureofthe
paste.

Coolthepiesthoroughlybeforeaddingthejelly.

Considernotusingjellyinthepiefilling.
Reference
Cauvain,S.P.,Young,L.S.,2008.BakeryFoodManufacture&Quality:WaterControland
Effects,seconded.Wiley-Blackwell,Oxford,UK.
368
BakingProblemsSolved
7.2.11Wearehavingdifficultyinblockingoutsavourypie
pasteinfoils,thereisatendencyforthedoughtosticktothe
dieblockcausingthebaseofthefoilcasetobecomemisshapen.
Chapter|7
7.2.12Whydoourbakedpastriesandquicheshavesmall
indentsinthebasewhichprojectupwardsandarepalein
colour?Theyarebakedinindividualfoils.
Thisproblemhasasimilarcausetothatdescribedforfermentedproductsin
pans(see
Section4.1.1
andthefoilcaseduringbakingandasitcannotimmediatelyescapethen
pressurebuildsupinsomeareasandforcesthepastryupwards.As
thepastryhasnotcoloured,itislikelythatthiseventhasoccurredearlyin
thebakingprocess.
Inthecaseofthepastry,thepressuresencounteredintheblockingpro-
cessitselfhelpstocreatetheimpermeablesealwhichisnecessaryforthe
steamtoremaintrapped.Itmaybethatsomeoftheindentiscreatedasthe
diewithdraws,thoughevenhand-blockedproductshavebeenknownto
showthisparticularproblem.
Themostobvioussolutiontoyourproblemistousefoilswithsmallper-
forationsinthebase.However,youshouldlookcloselyatthelocationofthe
holeswhichshouldbeatthelowestpointofthefoil,orifthefoilconcerned
hasmorethanonelowpointthenholesshouldpresentineachofthelow
areas.Eventhoughtheholesaresmallinsize,typicallylessthan1mm,the
pressuregeneratedbythehotgaseswillstillallowthesteamtodiffuseout
throughthem.
Iftheproblempersists,youshouldlookatyourbakingconditions.The
problemisalwaysexacerbatedbybakingathightemperaturesforshort
timesandwithhighbottomheat.Ifyoususpectthatthisisthecase,thentry
reducingthetemperatureandincreasingthebakingtime.Allowingthepastry
casetorestafterblockingandbeforefillingandbakingcanalsoreducethe
problem.
370
BakingProblemsSolved
ourapplepiescrispereating?
cussedforsavourypastry(see
Section7.2.10
),namelythatitarises
becauseofmovementofmoisturefromthemoistfillingtothedrier,
lowerwateractivitypastry.Incontra
sttothesituationinasavouryprod-
uct,therearemanymorewaystoexte
ndthecrispnessofsweetenedpas-
tryproductsduetothegreaterpotentialforrecipereformulation.
Potentialwaysofkeepingyourpastrycrisperincludethefollowing:

Loweringthestoragetemperatureforthebakedproducts.

throughreformulation.Thiscanincludetheadditionofsugartothepas-
tryorfilling,ortheadditionofhumectantssuchasglyceroltothefilling.

Omitorreducebakingpowderfromthepastryformulationtoreducepas-
tryporosity.

Ensurethatanystabiliserinthefillinghashadsufficienttimetobecome
effective.Somestabilisersmayrequireseveralhoursafterhavingbeen
blendedintothefillingbeforetheyachieveoptimumcontroloverwater
activity.
filling.Anysuchbarriermustbeed
ibleandshouldnotsignificantly
changetheproductcharacter.
Cauvain(1995)
providedsomeexamplesof
suitablemoisturebarriers(see
Fig.7.11
):

Aproteinsolution

Eggalbumensprayedontothepastrybefore
depositingthefilling.
FIGURE7.11
Effectofbarrieronshortpastrycrispness.
Pastries
Chapter|7
371

Agumsolution

depositingthefilling.

Aricepaperdiscplacedonthepastrybeforedepositingthefilling.
Reference
Cauvain,S.P.,1995.Puttingpastryunderthemicroscope.BakingIndustryEurope,68

69.
Furtherreading
Cauvain,S.P.,Young,L.S.,2008.BakeryFoodManufacture&Quality:WaterControland
Effects,seconded.Wiley-Blackwell,Oxford,UK.
372
BakingProblemsSolved
7.2.14Howdoweavoidboil-outofourpiefillings?
Theboiling-outofpiefillingsismostreadilycontrolledbyadjustingthe
bakingconditionsyouareusing.Commonly,productsarebakedtoadesired
colour;therateatwhichweachievetherequiredcolourdependstoalarge
extentonthechoiceofbakingtemperature.Boil-outofthefilling,however,
willdependmostlyonthelengthofthebakingtime;thelongertheproduct
spendsintheoventhehigherthefillingtemperaturewillbecomeandthe
greaterthechancesofboil-out.Wesuggestthatyouconsiderincreasingthe
oventemperatureandshortenthebakingtime.
needtoreducethelevelofsugarthatyouareusingintherecipe.Ifyouare
usingglucoseoranotherreducingsugar,youmayneedtoreplacepartorall
ofitwithsucrosetolimitthedegreeofbrowning.
Alternatively,considerloweringthewateractivityofthefillingbyadjust-
ingthesolublesolidsofthefillingformulation.Thelevelofsolublesolidsin
piefillingscontrolstheboilingpointoftheliquidinthefilling,thehigher
thesolublesolidscontentthehighertheboilingpoint(
CauvainandYoung,
2008
).Youcanthereforeraisetheboilingpointbyincreasingthelevelof
weightbasis.Rememberthatifyouuseaglucosesyrupthenyoumustbal-
ancethewateradditiontocompensateforthatpresentinthesyrupotherwise
thefillingwateractivitymaynotfall.
Reference
Cauvain,S.P.,Young,L.S.,2008.BakeryFoodManufacture&Quality:WaterControland
Effects,seconded.Wiley-Blackwell,Oxford,UK.
Pastries
Chapter|7
373
7.2.15Wewishtoreusepastrytrimmingsbutfindthat
Chapter8
OtherBakeryProducts
8.1WHATARETHEMOSTIMPORTANTFACTORSWHICH
CONTROLTHEVOLUMEOFCHOUXPASTEPRODUCTS?
Whenchouxpasteisbeingbakedanyairthathasbeenbeatenintothepaste
willexpandandthewaterwillbeconvertedtosteam.Theexpandedairand
steamtrytoescapebuttoalargeextentarepreventedfromdoingsobecause
eggalbumen.Theeggalbumen(protein)isextensibleandwillbeinflated
anddistendedbytheinternalpressuresofthegases

airandsteam.
Expansionofthepasteonlyceaseswhentheeggalbumencoagulates,
andbothitandtheglutenfilmlosetheirextensibilityandgas-holding
powers.Eggalbumencoagulatesathightemperaturesandlosesitsextensi-
bility,sothetemperatureofthepasteatwhichtheeggsareaddedisan
ofun-coagulatedeggproteininthepastewhenitgoesintotheovenisofthe
utmostimportancefortheachievementofgoodvolumeinthebakedproduct.
Iftheeggsareaddedtothepastebeforeithasbeenallowedtocoolade-
quately,thefluidityoftheeggsisquicklylostandthepenaltyislowervol-
ume.Pastescanbelefttocoolto24

41

C(75

106

F)naturally,bystirring
withthebeatersofthemachineorbybeingspreadoutontoacoldcleanslab
ortable-top.Aneconomicadvantageofcoldpasteisthatitrequirestheaddi-
tionoflesseggandwillstillgiveagoodvolumeproduct.
Theconsistencyofthepasteforchouxpastryisanotherofthecritical
factorsincontrollingthevolumeofchouxproducts.Italsoplaysaprominent
roleintheappearanceoftheproduct.Ideally,thepasteshouldbeassoftas
possiblebutwithoutcausingtheresultantpastrycasetobeofpoorshape.
Ifthepasteistoostiffwhenmakingeclairs,theybecomeunattractivein
appearanceandexhibitharshsurfacecracksandbreaks.Ifthepasteistoo
soft,theyneedmorebakingtodrythemout;otherwise,theywillcollapse
onbeingtakenfromtheoven.Eveniftheyareadequatelydriedouttopre-
ventthemfromcollapsing,theywillhavealowervolumeandlook
squashedinappearance.Whentheconsistencyiscorrect,theyarebeau-
tifullyrounded,andhavenoharshbreaks,burstsorcrackstodetractfrom
theirappearance.
375
BakingProblemsSolved.DOI:
http://dx.doi.org/10.1016/B978-0-08-100765-5.00008-4

2017ElsevierLtd.Allrightsreserved.
thanforeclairs.Againhoweverifthepasteismadetoosoftthebunswillbe
ofpoorshapeandcancollapse.Soalthoughitisagoodplantomakechoux
pasteslightlysofterwhenmakingcreambuns,thedifferenceisonlyslight
andmustnotbeover-done.Whenbakingchouxbuns,itisessentialtocreate
steamundersufficientpressuretoaerateorinflatethemasfullyaspossible
beforethecoagulationoftheproteinsandbeforesurfacedryingorcrustfor-
mationoccurs.Thisisachievedbybakingthepasteinacomparativelyhot
oven,227
C(440
F),sothatsteampressureisbuiltuprapidlytoexpandthe
pasteandtoholditinthatconditionuntilthecoagulationoftheproteinsand
thecrustformation.
Frozenandspraydriedeggaswellasliquideggsareregularlyusedin
theproductionofchouxpastry.Caremustbetakenwhenusingspraydried
eggthattheegghasnotbeenkepttoolongasinstorageeggproteinsare
degradedthroughtheactivityofbacteria.Frozeneggsshouldbedefrosted
beforeuse.Someadjustmentinrecipesmayberequiredwhenusingfrozen
eggastheremayhavebeensomechangeineggviscosityasaresultofthe
freezing/thawingoperation.
BakingProblemsSolved
8.2WHYARECREAMBUNSBAKEDUNDERCOVERSAND
ECLAIRSARENOT?
Ahighervolumeisusuallyrequiredforcreambunthane
clairshells.To
achievethishighvolume,thesurfaceofthebunshouldremainmoistforas
longaspossibleinthebakingprocess.Whenthebunsareplacedinthe
oven,theheatgraduallybeginstoexpandtheairbeatenintothepasteandto
generatesteamfromthemoistureintheproduct.Ifthebunswerebakedina
Chapter|8
8.3OURCHOUXBUNSCOLLAPSEDURINGBAKING.CAN
YOUSUGGESTWHYTHISHAPPENS?
Itisimportantwhenbakingchouxpr
oductsthattheoventemperature
issufficientlyhightoimpartheatquicklyatthestartofbaking.
Consequently,arapidrecoveryofthe
bakingtemperatureaftertheproduct
hasbeenloadedintotheovenisvital.
Chapter|8
8.5WHYISPOWDEREDAMMONIUMCARBONATEOR
VOLADDEDTOCHOUXPASTE?
Powderedammoniumcarbonate,orvolasitiscommonlyknown,is
entirelydifferentfromotherbakingpowdersusedinbaking.Whenheated,
thewholeofthematerialturnsintothreegases
ammonia,carbondioxide
andwatervapour
andnoresidueremainsintheproductintheformofa
salt.Notallthegasesescapewiththeresultthatasmellofammoniaremains
aftertheproductsarewithdrawnfromtheoven.Thisisbecauseammoniais
extremelysolubleinwater.Noactiontakesplaceuntiltheproductsare
heated.Volshouldbestoredinanairtightcontainertomaximiseitssubse-
quenteffectiveness.
Whenaddedtochouxpasteinsmallquantities,ithelpstoimprovethe
volume,especiallyinthecaseofcreambunsasthesearerequiredtobe
extremelylightincharacterandtohavethegreatestpossiblevolume.Itis
notalwaysnecessarytoaddvoltochouxpastetoobtaingoodvolumeif
thechouxproductsarecorrectlymade.Neitherisitnecessarytoaddvol
whenmakinge
claircasesasthereisatendencyforthepastetoblowtoo
much,thusspoilingtheshapeoftheeclairs.
BakingProblemsSolved
8.6WEWISHTOMAKEALARGEBATCHOFE
CLAIRCASES
ANDSTORETHEMFORAFEWDAYSBEFOREFILLINGAND
ICINGTHEM.CANYOUADVISEONTHEBESTWAYTOKEEP
THEMTOPRESERVETHEIRQUALITY?
Makinglargequantitiesofeclairsforstoragebeforefinishinghastobe
undertakenwithcareasthecharacteristicsoftheproductdonotlendthem-
selvestostorageforlongperiods,exceptundercarefullycontrolledcondi-
tions.Therearetwopotentialqualitylossesduringstorage;theyaretheloss
orgainofmoisture.Bothcanadverselyaffecttheeatingcharacterofthe
finalproduct.
claircasesareexpectedtobedryandcrispeatingbutnothard.Initially
afterbaking,thecasesshouldbequitefirm.Themoisturecontentatthecen-
treofthecasemayoftenbehigherthanthatatthesurface.Itistherefore
importanttominimisefurthermoisturelossesfromtheproductsurfacedur-
ingcooling;otherwise,themoisturegradientfromtheinsidetooutsideof
thecasewouldbeincreasedandmaycausethecasetocrackandinextreme
cases,fallapart.Ifbakingisextendedtoolong,thenthecasesmaybecome
toohardeating.
Thecasesshouldbeallowedtocoolthoroughlybeforebeingstoredina
closedcontainerorroom.Condensationshouldbeavoidedasthiswillcause
softeningoftheproducts.Astheyhavealowmoisturecontent,e
claircases
arepronetoabsorbingmoisturefromtheatmosphereandsoshouldbestored
atalowrelativehumidityorinairtightcontainers.
OtherBakeryProducts
Chapter|8
8.7WESTANDOURFINISHEDCHOUXBUNSONU-SHAPED
CARDBOARDANDWRAPTHEMINACELLULOSE-BASEDFILM.
RECENTLY,WEHAVEOBSERVEDTHEGROWTHOFMOULD
COLONIESONTHEPRODUCTS.WHYISTHIS?
Ingeneralchouxproductswithfilling
saresusceptibletomouldgrowth,
andiftheproductsarewrapped,thed
angerofmouldisincreasedbecause
ofthegreaterdegreeofmoisturewhichismaintainedaroundthechoux
bunsbythecellulosewrapper.Thecardboardonwhichyouholdthepro-
ductswillabsorbwaterfromthepro
ductbecauseofmoisturemigration
andtheinfluenceofgravityonsomeofthemoisture.Itisimportantthat
goodhygienepracticesareobservednotonlyintheproductionprocessbut
alsointhestorageofboththeU-shape
dcardboardandthecellulosewrap-
pingfilm.Bothcardboardandwrapp
ingfilmshouldbestoredcoveredina
cleandryplace.
Fromthehygienepointofview,thesurfaceofthechouxproducts
shouldbecoolanddrybeforefillin
gandcoating.Theyshouldbekept
coveredwhilstcoolinganddrying-
8.8OURSCONESAREMADEFROMFROZENDOUGHBUT
FREQUENTLYLACKVOLUME.WEALSOFINDTHATTHE
CRUMBCOLOURISRATHERBROWN.CANYOUOFFER
SUGGESTIONSTOIMPROVEOURPRODUCTQUALITY?
Sconesdependonchemicalraisingagentsfortheirvolume.Oncetheraising
agentscomeintocontactwithwater,thechemicalreactiontoproducecarbon
dioxidebegins.Intheproductionofafrozensconedough,someofthisaera-
tioncapacitywillbelostasthereactionsstart,andthiswillleadtoalossof
volumeinthebakedproduct.Toovercomethislossofaeration,achangeto
asloweractingacidwillhelp,e.g.,sodiumacidpyrophosphateorsodium
acidaluminiumphosphate.Thelevelofbakingpowdershouldbeabout5%
onflourweight.
Alternatively,youcouldtryusinganencapsulatedformofsodiumbicar-
bonateorthebakingacid.Theencapsulationisusuallywithfatwhichdelays
theproductionofmostofthecarbondioxidegasuntiltheproductentersthe
ovenandthefatmelts.
Chapter|8
8.9SOMEOFOURSCONESHAVEACOARSEBREAKAT
THESIDEANDANOPENCRUMBCELLSTRUCTUREBUTTHE
RESULTSARENOTCONSISTENT.CANYOUPLEASESUGGEST
8.10WEWISHTOEXTENDTHESHELF-LIFEOFOUR
SCONES.HOWCANWEDOTHIS?
Thestalingofsconescanbereducedinanyofthefollowingways:
Wrappingsconesinamoistureprooffilmwillreducemoisturelossand
giveasoftereatbutwillnotpreventinherentstaling.
Sconescanbefrozen,butthereisusuallyalossinqualityassociated
withthisprocess;inparticular,theproductsmaybecomecrumblyon
defrosting.
Iffreezingisnotanoption,thenincludingasuitableemulsifier(e.g.,a
highmonoglyceridetypeofglycerolmonostearateinemulsionorpaste
Chapter|8
8.11THESURFACEOFOURSCONESISCOVEREDWITH
SPECKLESOFAYELLOWISH-BROWNCOLOUR.WEAREUSING
GDLASTHEACIDCOMPONENTINTHEBAKINGPOWDER.
CANYOUSUGGESTWHYWEHAVETHISPROBLEM?
Thediscolourationisprobablyduetounreactedbicarbonateinthesconemix-
ture.Oftensmallbrownspecksindoughscanbeattributedtoundissolved
particlesofsodiumbicarbonate.Inthiscase,theproblemcanbesolvedby
usingafinerparticlesize(sieveofaperturesize0.06mm).Alternatively,rest-
ingthedoughforatleast40minutesallowsthebicarbonatetodissolveand
ensuresthatthespecklesdonotoccur.Ifglucona-delta-lactoneistheneutra-
lisingacid,itrequirestimetohydrolysetogluconicacid.Givingalonger
restingtimebeforethesconesarebakedmayresolvetheproblem.
BakingProblemsSolved
8.12WHYSHOULDPARTICULARCAREBETAKENWHEN
WASHINGSCONESWITHEGGWASHTOENSURETHAT
NONERUNSDOWNTHESIDESOFTHEPIECESOFDOUGH?
Afterrollingandcuttingoutsconedoughintoroundorfingershapes,the
surfaceofthesconeiscommonlywashedwitheggtoobtainaglossy,rich
brownskinonbakingwhichmakesthemsoattractive.Iftheeggwashis
allowedtorunordribbledownthesidesofdoughpieces,theirbakedappear-
anceisspoiled.
Whenthesconesarebaked,theeggonthesidewallswillcoagulatelong
beforethebakingpowderinsidethesconehasevolvedallofitscarbondiox-
ide.Thiscoagulatedeggwillformamoreorlessun-yieldingbanduniting
thetopskinwiththebottomedgeofthesconeandwillpreventthatside
fromrisingtoitsfullheight.Thegasproducedbythereactionofthebaking
powdermustcauseexpansioninsomedirectionorotherandwilltakethe
lineofleastresistance.Thiswilloftencausetheoppositesideofthescone
toriseevenhigherthanotherwisewouldhavebeenthecase.Theendresult
isthatthesconerisesunevenlyandwheretheeggrandownthesides,itwill
bespoiledbyayellowstreakrunningfromtoptobottom,insteadofthe
sidespresentinganunbroken,smooth,whitecolour.
Chapter|8
8.13WEAREFREEZINGARANGEOFUNBAKED,
CHEMICALLYAERATEDPRODUCTSINCLUDINGSCONES
ANDCAKEBATTERSANDNOWWANTTOINCLUDESOME
VARIATIONSUSINGFRESHFRUITS.WEHAVECARRIEDOUT
ANUMBEROFTRIALSANDHAVEARANGEOFISSUES
WHICHAREMOSTLYRELATEDTOTHEFRAGILITYOFTHE
FRUIT.CANYOUPROVIDESOMEADVICE?
Youhaveclearlyrecognisedthemainproblemwithusingfreshfruitsinthat
theskinsofmostofthemtendtobesusceptibletomechanicaldamage,and
thiscanleadtothebleedingofthecontentsintothedoughorbatter.On
defrostingandbaking,acommonlyobservedproblemisthepresenceofdisco-
louredstreaksinthebakedcrumb.Thecolourofthesestreaksvariesaccording
tothefruitbeingaddedandthepHofthedoughorbatter(see
Section10.1
foranexplanationofthepHscale).Therearemanynaturallyoccurringcol-
oursinfruitswhichcancontributetothecolourchangeanditcanoccurin
manydifferentsituations(forexamples,see
Sections5.21
and
5.23
).
Someoftheproblemswiththefragilityoftheskinaremanifestatthe
doughandbattermixingstage.Youshouldtrytodelaytheadditionof
fruitsaslateaspossibleinthemixingprocessanduseaslowaspeedas
ispossibletodispersethefruits.Itispossibletoobtainsomefruits
alreadyfrozen,andthismakestheproductmorerobust(providedyoudo
notletthemdefrost).However,youshouldstilltrytoaddtheseproducts
quicklyaspossible.
Inyourcase,theproblemisexacer
batedbythefreezi
ngandthawing
processthatyouareemploying.Fres
hfruitsarehighinmoisture,often
around60

70%orhigher.Astheunbakedp
roductsbegintofreeze,ice
crystalsbegintoformwithinthecells
ofthefruitmatrix.Asthetempera-
turecontinuestofall,thecrystalscangrowverylargeandbegintopunc-
turethefruitskins.Inthefrozenstate,notmuchchangetakesplace,but
whentheproductsaredefrosted,theicecrystalsmeltandleaveholesin
thewallsofthefruitsandthecellcontentsbegintoleakout.Youarenot
re-mixingthedoughorbatterandsoyoumightexpectthattheproblems
wouldbelimited.Indeed,theyarebutwhattendstohappenisthatthe
crumbimmediatelyaroundthefruitspiecesisaffected,andyouoften
canbejustasundesirableasdisco-
louredstreaks.
Toreducetheproblems,youshouldlookatyourfreezingoperation.In
general,rapidfreezingfavourstheformationofsmallericecrystals,andthis
cancontributetoareductioninthedamagetotheskinsofthefruit.
However,youneedtorememberthatittakessometimeforthecoldfrontin
adeepfreezetotraveltothecentreofproducts,soitisnotsimplyacaseof
388
BakingProblemsSolved
loweringthetemperatureofthefreezer.Youwillneedtocheckthetimethat
ittakesforthecoreoftheproductstobefrozenbecausethepotentialforice
crystalgrowthisgreaterintheproductcore.
Itmaybethatyouwillneedtoturntousingablastfreezerratherthana
staticone.Intheblastfreezer,themovementoftheairacrosstheproduct
speedsupthefreezingprocessandwillhelpinthereductionoftheicecrys-
talsizeinthefruits.However,thereareotherissuestoconsiderwithblast
freezing,andoneoftheseisthattheairmovementcanremovesomeofthe
productmoisture(1
2%),soyouwillneedtocheckthatthisdoesnot
adverselyaffectthefinalproductwhenbakedandeaten.
Intheory,ifyoucouldstopthefruitpiecesfromfreezing,thenyouwould
preventtheformationoficecrystalsandinturn,wouldeliminatedamageto
theskins.Suchprocessesareoftenreferredtoascryo-protectionandare
oftenbasedontheinfusionofmaterialslikeglycerol(glycerine).Bywayof
anexampleastohowthismightwork,tolowerthefreezingpointbyabout
C(e.g.,tokeepthematerialun-frozenat
C,atypicalfrozenstorage
temperature),youwouldaneedaconcentrationofabout50%glycerol/50%
water,andthiswouldneedtobeinfusedintothefruit.Apotentialproblem
couldbethechangeinproductflavour.
OtherBakeryProducts
Chapter|8
8.14WEHAVEBEENASKEDTOIMPROVETHESENSORY
QUALITIESOFOURSCONESANDHAVEBEENABLETODO
THISBYANUMBEROFRECIPECHANGES.ALTHOUGHTHESE
CHANGESHAVEBEENLARGELYSATISFACTORYFOROUR
TOBETOODRYEATING.DOYOUHAVEANYSUGGESTIONS
ASTOHOWWECANMAKETHEMMOREMOISTEATING?
Acommonproblemwithfruitedbakedproductsisthatthecrumbofthe
productstendstobecomedryeatingwithextendedshelf-life(see
Section
5.28
).Thisproblemismostcommonlyassociatedwiththemigrationof
moisturefromthecrumbtothedriedfr
uitinclusions.Typically,themois-
turecontentofthedriedfruitsarelessthan20%torestrictthepotential
formicrobialgrowthduringtheirs
torage;thisisalittlelowerthanthe
moisturecontentofyourplainscones,butthesugarcontentofthedried
fruitsisveryhigh,oftenaround60%.Thiscombinationoflowermoisture
andhighersugarinthefruitpiecesmeansthatthenaturalmovementof
waterisfromthecrumbofthesconetothefruitpieces.Someofthis
moisturemigrationwilloccurduringt
hebakingprocess,butasignificant
proportionwilloccurduringstorage.T
hismoisturemigrationphenomenon
explainswhytheproblemisnotreadilyobservedwiththefreshsconesbut
becomesincreasinglyapparentdur
ingtheirstorage.Inthecaseofthe
sconesthatyoumakewithpiecesofca
ndiedfruits,theproblemiseven
greaterbecausethefruitpieceshaveevenhighersugarcontents.
Themostusualwaytoimprovetheeatingqualityoffruitedproductsinthese
circumstancesisbysoakingthefruitpi
ecesforashortperiodoftimetoraise
theirmoisturecontents(
CauvainandYoung,2008
).Whentheexcessmoisture
isdrainedaway,someofthesugarwhichhadbeenpresentwillbelost,andthis
doublechangewillreducethedrivingforceformoisturemigration.
However,raisingthemoisturecontentofthedriedfruitpiecesisnot
withoutitspotentialproblems.
1.
Theskinsofthesoakedfruitbecomemorefragile,sothereisatendency
forthemtobreakduringmixingleadingtodarksteaksinthecrumb.
2.
Theoverallmoisturecontentofthesconeanditsequilibriumrelative
humidity(ERH)canincreasewhichincreasesthesusceptibilityofthe
wrappedproducttomouldgrowth.Youwillneedtocheckthiscarefully.
Reference
Cauvain,S.P.,Young,L.S.,2008.BakeryFoodManufactureandQuality:WaterControland
Effects,seconded.Wiley-Blackwell,Oxford,UK.
390
BakingProblemsSolved
8.15WEMAKEANDBAKESCONESONADAILYBASIS.
RECENTLY,WEPLACEDTHEMUNBAKEDINAREFRIGERATOR
INSTEADBUTWESTILLFINDTHATTHEPRODUCTSWERE
SCONESANDSTILLPRODUCEANACCEPTABLEPRODUCT?
refrigeratorforstor
ingunbakeditems.
Thisisbecausethesurfaceareaofthecool
thaninarefrigeratorwhichhelpsmaintai
nahighrelativehumidityandmoisture
intheunbakedproduct.Asaruleofthum
b,youshouldkeepunbakedproducts
theproduct.Inpracticetemperatures,around
2
3

Carequitesuitable.
However,yourproblemistodowiththelossofcarbondioxidefromthe
dough.Evenatrefrigeratedtemperatures,thereisprogressivereactionof
doughthecarbondioxidegasgeneratedisfreetoescapetotheatmosphere.
Thisiswhyyourproductsarelosingvolumewhenyoubakethemoff.
Therateatwhichthecarbondioxidegasislostdependsontherateofreac-
tionofthebakingpowder(see
Section5.37
).Evenifyouareusingtheslower
actingbakingacids,longstoragetimeswillallowforsignificantreactionand
lossofcarbondioxidegas.Youmayfindthatbyincreasingthelevelofbaking
powderyoucanrestoresomeoftheproductvolumeonbake-off,butthehigher
levelsofresidualsaltswillchangetheflavourprofileofthebakedproduct.
Analternativewouldbetoswitchtousingamicro-encapsulatedbaking
acidorsodiumbicarbonate.Thecoatingdelaysthereactionofthebakingpow-
dercomponents,soitshouldhelpdelaymuchofthegasproductionuntilthe
bake-offperiod.Anexampleofsuchanapproachisillustratedin
Fig.8.1
;note
youcannotexpecttousetheencapsulatedmaterialforyourfreshsconeproduc-
tion.Thereareanumberofcommerciallyencapsulatedproductsavailable.
2
2.1
2.2
2.3
2.4
2.5
2.6
2.7
2.8
01020304050
Specific volume (ml/g)
Standard bicarbonate
Encapsulated bicarbonate
FIGURE8.1
Comparisonofcarbondioxideevolutioninsconesduringrefrigeratedstorage.
OtherBakeryProducts
Chapter|8
391
8.16IAMHAVINGDIFFICULTYWITHROYALICING
WHICHWILLNOTHARDENADEQUATELY.
CANYOUADVISE?
ToobtainhardRoyalicing,thereareseveralpointswhichyoushouldaddress.

Themixingbowlinwhichtheeggwhitesarebeatenshouldbecompletely
freefromgrease.Evensmalltracesofgreasewillaffecttheaerationofthe
eggalbumen.Iftheicinghasnotreceivedadequateaeration,itwillhave
asfasterspeedstendtoresultinlargebubblesintheicing.Forthesame
reason,itisadvisabletomixwiththebowlabouthalffullbeforebeating.
Whentheicingisapplied,itshouldbeworkedlightlyonthesurfaceofthe
caketobreakdownanylargebubbleswhichmaystillbethere.

flinty,shouldbekepttoaminimumasanexcesswillpreventtheicing

Ifmakingtheicingforrunoutwork,itshouldbethinnedwithegg

shouldalsobestoredinadryatmosphere;otherwise,theicingwillsoften
asitabsorbsmoisturefromtheatmosphere.

IftheRoyalicingistobeappliedtoacakecoveredwithalmondpaste,it
isbesttoallowacrusttoformonthepasteovernightinawell-
ventilated,warm,dryarea.Insuchcases,twocoatsofRoyalicingare
normallyadequatewiththefirstcoatbeinglightandofnormalpiping
consistencyandbeingallowedtodryovernight.Thesecondcoatmaybe
slightlysoftertogiveasmootherfinish.Ifthepastehasatendencyto
oil,orifthereisinsufficienttimetoallowtwocoatstobeapplied,hot
fondantmaybeusedtosealthesurfaceofthepaste.

cosecontentwillavoidtheuptakeofmoistureandagumorstabilising
materialshouldbeincluded.
Furtherreading
Bent,A.J.,1997.TheTechnologyofCakemaking,sixthed.,BlackieAcademic&Professional,
London,UK.
392
BakingProblemsSolved
8.17IHAVEHEARDTHATOFF-ODOURSCANBECAUSED
BYTHEICINGUSEDFORCAKEDECORATIONS.
ISTHISTRUE?
Theicingitselfshouldnotcauseoff-odours.However,thevarnishusedon
Chapter|8
8.18AFTER2DAYSOURROYALICINGTENDSTOTURN
YELLOW.CANTHISDISCOLOURATIONBEPREVENTED?
Therearemanycausesofdiscolourationinroyalicing.Somearelistedbelow:
Royalicingmadewithinferiortypesofalbumensubstitutesorweak
albumensolutionswillslowlydiscolouronageingandbecomeslightly
yellow.Usinggoodquality,ingredientsshouldpreventtheproblem.
Theuseofpoorqualityicingsugarsproducesapoorcolourintheicing.
8.19WEARERECEIVINGCOMPLAINTSOFOPAQUESPOTS
ONOURFUDGEICING.CANYOUSUGGESTAREMEDY?
Spotsonfudgeicingaretheresultofrecrystallisationofthesugar.Thesugar
grainingiscausedbyinsufficientmixingorbyover-heatingorbylossof
moisturefromtheicingtothecakeoratmosphere.
Toavoidmoisturetransfer,thecakeshouldbebrushedoverwiththe
boilingpureebeforeicing.Addingglycerinetotheicingatarateof0.5%
willhelpkeepthefudgeicingsoftandlowerstheERHoftheicingbring-
ingitnearertotheERHofthecakewh
ichwillalsohelpreducemoisture
OtherBakeryProducts
Chapter|8
8.20AFTERSTORINGOURCOATEDPRODUCTS
OVERNIGHT,WEFINDTHATCRACKSFORMINFONDANT
COATING.CANYOUSUGGESTWAYSTOOVERCOME
THISPROBLEM?
Manyfaultsencounteredwithfondantareassociatedwithoneormoreofthe
following:

TheERHofthecomponentsoftheproduct.

Thedegreeofmoisturepermeabilityofanywrappingmaterial.

Theglucosecontentofthefondant.
Fondantscanremainsoftorbecomeharddependingontheformulation
andprocessusedfortheirmanufacture.Surfaceproblemswithfondantsuch
aswhitespots,streaksorstickinessalsohavesomeoftheirrootsinthefor-
mulationandprocessing,andothersinthestorageconditionsandcompo-
nentsonwhichtheysit.
Cracksthatappearonthesurfaceoffondantarearesultofthefondant
dryingoutandhardening.Aglucosesyruplevelbelow12%totalweight
recommended.Inclusionof5to10%hardfatsuchashardenedpalmker-
neloilorahigh-ratiofatcontaining
anemulsifiercanbeusedtoprevent
hardening.
Thereverseoftheproblemwithhardeningisthatofthefondantbecom-
ingsticky.Thecauseofthisisthehygroscopicnatureofthefondant.When
storedinahumidatmosphereorsurroundedwithpackagingfilmoflowper-
meabilityormoisturevapourtranspirationrate(see
Section11.7
),theERH
ofthefondant,beingverymuchlowerthanitssurroundingatmosphereand
thepresenceofundissolvedsugarcrystals,causesuptakeofmoisture.This
resultsinthefondantbecomingsticky.Storageoffondantproductsina
withothergoodscouldaccentuatetheproblem.Thawingoffrozenproducts
inhighhumidityconditionscanalsocausetheproblem.
Inproductswherethefondanttoppingsitsonapastryproductwhichis
creamfilled(e.g.,chocolatee

clair),moisturemovesfromthecream(with
highERH),throughthepastrycasingtothefondanttopping(lowERH)and
duringtransportationoftheproductcancausethefondanttoslipoffthe
product(thethinfilmofwateractslikealubricant).Inthiscase,theproblem
Furtherreading
Cauvain,S.P.,Young,L.S.,2008.BakeryFoodManufacture&Quality:WaterControland
Effects,seconded.Wiley-Blackwell,Oxford,UK.
396
BakingProblemsSolved
8.21WEMAKESUGARPASTESHAPESANDSTORETHEM
INPLASTICCONTAINERSFORLATERUSE.INAFEWDAYS,
THESHAPESSOFTENANDAREINCLINEDTODROOP.
CANYOUSUGGESTHOWWEMIGHTOVERCOME
THISPROBLEM?
Ifyourcontainersarenotsealed,thenthesugarshapescantakeupmoisture
fromtheatmosphere.Generally,therelativehumidityoftheatmosphere
indoorsisintherange40
70%,sosugarpasteshapeswithalowERHwill
absorbatmosphericmoisture.Youshouldtrytominimisetheheadspacein
thecontainerusedtostoretheshapeswhichwilllimitthemassofwater
availableforabsorptionbythepaste.
Itispossiblethattheformulationofthesugarpastecontainstoomuch
humectantforyourrequirements,andwesuggestthatyoureducethepropor-
tionuntiltheERHisintherange75
OtherBakeryProducts
Chapter|8
8.22WEWOULDLIKETOSTOREOURHEAVILYFRUITED
WEDDINGCAKESAFTERCOATINGWITHMARZIPAN
FORSOMETIMEBEFOREWEICETHEMBUTFINDTHAT
THEMARZIPANHARDENS.WHYISTHISANDHOWCAN
WEACHIEVEOURAIMS?
Heavilyfruitedweddingcakescontainmanyingredientswhicharegoodat
holdingontothemoistureandcollectivelycausethecaketohavealow
wateractivityvalue.Marzipanhasahighermoisturecontent,anditsingredi-
entsarenotsopowerfulatholdingontothemoistureandsohasahigher
ERH.Consequently,moisturewillmovefromthemarzipanintothecake
thuscausingthemarzipantodryandharden.
Theadditionofsomeglucose,whichaswellashelpingtoreducesugar
(sucrose)crystalsize,actsasahumectantandthushelpstopreventmoisture
lossshouldovercometheproblem.Wewouldsuggestthatyouuseeither
stocksyrup(boil1kgsugar,1Lwater,250gglucose,allowingittocool
beforeuse),oramixtureof50%glucose,50%water,ratherthanwater
alone,forsofteningpurposes.
BakingProblemsSolved
Chapter|8
8.25WHENMAKINGITALIANMERINGUES
WHYISTHEBOILINGSUGARWATERADDEDSLOWLY?
Oneoftheeffectsofaddingboilingsugarwatertothebeateneggwhitesis
thattheairwhichhasbeentrappedbythealbumenisheatedandexpands,so
thatthevolumeofthemeringuefoamincreasesconsiderably.Ifthesugaris
addedveryquickly,thealbumenwouldalmostimmediatelycoagulate.In
thiscondition,itismuchlesselasticandanyexpansioncausestheaircell
wallstobreakandreleasetheircontents.Thus,themeringuewouldbecome
heavierratherthanlighter.
Addingthesugarsolutionasagradualstreamwhilststillwhipping,the
temperatureofthemixtureisslowlyincreased.Expansiontakesplaceand
themeringuebecomeslighter.Furtherwhenhotsugarsolutionisadded,the
temperatureincreases,andbythetimeallthesugarisadded,itwillbecome
sufficientlyhightocoagulatethethinfilmsofexpandedalbumen.Eachcell
willbefilledtocapacitywithexpandedair.
Themeringueshouldstandwellwithoutlossofaerationforprolongedperi-
ods.ThisexplainswhyItalianmeringuemaybeusedformakingbuttercreams.
Aftermixingthemeringueandthebutter,thereshouldbelittlebreakdownof
theaircellsaseachiscoatedwithadelicateskinofcoagulatedalbumen.
Coldmeringue,ontheotherhand,readilybreaksdowninbuttercream
becausetheun-cooked,andthereforeun-coagulated,albumenchainsareeas-
ilyshortenedbycontactwiththebutterfat.Thecellsbreakopen,releasetheir
trappedair,andthebuttercreamlosesitslightnessandbulk.Marshmallow,a
gelatinousformofItalianmeringue,isoftenblendedwithbuttercream.Due
Chapter|8
8.26WEAREEXPERIENCINGCRACKINGOFOUR
MERINGUESHELLSDURINGBAKING.WHYISTHIS?
Whenthesugarconcentrationinthealbumenmixincreasesfrom2:1to3:1,
thereisanincreasedtendencyformeringueshellstocrackduringbaking.If
bakingiscarriedoutforshortperiodsoftimeathightemperatures,theprob-
lemisaccentuatedbecausethealbumenonthesurfacecoagulatesearlier
thaninthecentre.Beinghardandinflexible,itcannotmovewiththepres-
surecreatedbythestillexpandingcentreandsothesurfacecracks.
Thevapourpressureofthesugarsolutiondecreasesasthestrengthofthe
solutionincreases.Thismeansthatasthesugarconcentrationincreases,
moisturewillevaporatemoreslowlyduringdryingorbakingandwillcon-
tributetotheproblem.
Reducingthesugarconcentrationto1kgto400mLalbumenshould
help.Reducingthebakingtemperaturewillalsohaveabeneficialeffect.
BakingProblemsSolved
8.27WEAREHAVINGPROBLEMSWITHSOFTENINGOF
COFFEEMERINGUESINWHICHWEUSECOFFEEPOWDER
ASTHEFLAVOURING.ISTHISTHECAUSEOFTHEPROBLEM?
Addingcoffeepowderorcoffeeessencetotherecipedoesnotusuallycause
meringuestosoftenprovidedtheyarebakedthoroughly.Meringuesarenor-
mallybakedatabout116
C(240
F)for3hourstoensurethattheyare
Chapter|8
8.28ONSOMEO
CCASIONS,OURALMONDMACAROONS
EXHIBITVERYCOARSECRACKSONTHESURFACEINSTEADOF
THEFINECRACKSWEARESEEKING.WEHAVENOTBEENABLE
TOTRACETHECAUSE,CANYOUHELP?
Coarsecrackscanbecausedeitherbythedepositedmacaroonsforminga
skinbeforebakingorbyinsufficienthumidityduringtheinitialstagesof
baking.Ifaskinhasformed,thenthesurfaceisnolongerporousenoughto
allowthereadyescapeofmoisturevapourduringbaking.Insteadpressure
buildsupinsidethemacarooncausingtheskintoeventuallyformacoarse
crack.Toavoidthisproblem,donotleavetheproductstandinginawarm,
dryatmosphereandbakethemoffassoonaspossibleafterdepositing.
Mostproductscontaininghighpercentagesofsugarshouldbebakedina
coolerovenortheyburnrapidly.Sugarcaramelisesathightemperaturesand
becomeshard.Inthecaseofmacaroons,theovenshouldbecoolenoughto
allowtheproducttogrowbytheexpansionoftheaircellsbeatenintothepaste
andtoflowouttothecorrectsizebeforethealbumenoftheeggwhitesiscoagu-
8.29WHATARESTOTTYCAKESANDHOWARE
THEYPRODUCED?
Stottycakes(stotties)areatraditionalTyneside(north-eastregionof
England)delicacypreparedfromabread-likedoughenrichedwithfatand
sugar.AcloserelationisthebreadcakewhichisfoundinYorkshire.Both
productsarestrictlynotcakesinthattheyarenotpreparedfromadough.
Atypicalrecipeisasfollows:
%Flourweight
Flour100
Salt2
Lard5
Sugar1
Yeast5
Milkpowder2
Water,approx.57
Thedoughisscaledatabout340g(12oz)thenroundedandflattenedto
Chapter|8
8.30WHYDOESOURWHIPPEDCREAMCOLLAPSE
ONSTANDING?
Duringthewhippingofcream,themovementofthewiresofthewhisk
throughthefluiddrawinsmallbubblesofair.Fatchainsinthecreamform
attheinterfaceoftheairbubbleandtheaqueousphasewheretheystabilise
thebubblesandpreventthemfromrisingandescapingfromthecreamafter
mixing.Inthestablefoamwhichisformed,theliquidoftheaqueousphase
standing,thebubblesinthecreambecomeunstableandtheycollapse.In
escapesandusuallydrainsundertheinfluenceofgravity.Therateatwhich
thecreamwillcollapsedependsonthemanyfactorswhichaffectthestabil-
ityofthefoam.Asthemainstabilisingagentisthefatpresent,thereneeds
tobeaminimumof40%butterfattoproduceastablefoamstructure.
Theamountofstabilisingmaterialpresentlimitsthemaximumamount
ofairthatcanbebeatenintothecream.Thisisbecausethestabilisermust
belocatedatthebubblesurface.Thegreaterthequantityofairincorporated
intothebatterthelargerthesurfaceareathatneedstobestabilised.With
everincreasingquantitiesofairbeingincorporated,apointisreachedwhen
Toomuchairinthecreamwillmakeitunstableandmorelikelytocol-
lapsewithsmallchangesinstorageconditions,e.g.,asmallincreaseintem-
peraturecancausetheairtoexpandandincreasethesurfaceareathatmust
becoveredbythestabiliser.Theaerationofcreammaybeexpressedasrela-
tivedensityorspecificgravity(see
Section10.2
).Itisalsocommontosee
creamaerationexpressedasover-run.Thisisthereciprocalofdensity
expressedasapercentage(thusarelativedensityof0.77
5
130%over-
run).
Carefulcontrolofcreamtemperaturebeforeduringandafterwhipping
needstobetaken.Beforewhipping,ensurethatthecreamtemperatureis
3

5

C(38

40

F).If,foranyreasonthecreamtemperatureisabovethis,
thenchillitinarefrigeratoruntilitstemperaturehasfallentothislevelto
increasetheproportionofsolidfat.Duringwarmweatherinparticular,rinse
outthebowlandbeaterwithcoldorchilledwater,orpreferablyplaceina
refrigeratorforsometimebeforeuse.
Whiskthecreamonamediumspeeduntilitstartstothicken,thenfinish
whiskingonhighspeed.Duringwarmweather,thecreamshouldbewhisked
inasshortaperiodaspossibletominimisethetimeitisexposedtothehigh
atmospherictemperature.Aimtohavethewhiskedcreamatamaximum
temperatureof10

C(50

F)attheendofwhisking.Afterwhipping,thebulk
ofthecreamshouldbestoredinarefrigeratorat3

5

C(38

40

F),and
afterdepositing,thecreamtemperatureshouldnotbeallowedtoexceed
10

C(50

F).Abovethistemperature,thecreamwillstarttocollapse.
406
BakingProblemsSolved
Ifattentiontothecreamtemperaturecontrolisnotenoughtoovercome
theproblem,thenwesuggestincreasingthebutterfatcontenttoabout42%.
Ifyoursupplierisunabletoprovidethis,youcouldblendsixpartsbyweight
ofwhippingcreamcontaining40%butterfatwithtwopartsbyweightof
doublecreamcontaining48%butterfat.Itisnotuncommontoexperience
Chapter|8
8.31RECENTLY,WEEXPERIENCEDAPROBLEMWITHA
FISHYTAINTINABATCHOFBUTTERCREAM.CANYOU
SUGGESTWHY?
8.32WEAREEXPERIENCINGSEEPAGEOFOURJAMINOUR
FROZENFRESHCREAMGATEAUWHENTHEYARETHAWED;
CANWEAVOIDTHIS?
Seepageofthisnatureiscausedbytheformationofsurfacewaterthrough
syneresis(see
Section11.1
)withinthecreamandjamasaresultofthecrys-
tallisationoraggregationofpolymers.Itiscommonlyfoundwithproducts
whichundergofreezingandthenthawing.Surfacewaterformsbecauseofthe
breakdownofthecreamfoam.Inthecaseofjamseepage,thejamisbasi-
callyacolouredsugarsolutioncontainingfruitandthecolourisunlikelyto
beheldfast.Onceacolouredsolutionhasformed,itcandiffuseintothe
cream.
tiallythawedandthenfrozenagainasmightbeexperiencedwithrefrigerated
transport.Anytemperaturecyclingimpairscreamstability,andasaconse-
quence,thejamspreadsout.Ifthetemperaturecyclingintransportreaches
above
2
5

C(23

F),thentheseepageismorelikelytooccur.Wewouldnot
expecttoseesuchtemperaturechangesinawell-managedandmonitored
reasonablebarriertoheattransfer.Inaddition,astackoffrozengateau
shouldbehaveasareasonablecoldsink.
Thesolutiontotheproblemistoavoidperiodsofintermediatedefrosting.
Wheresuchperiodsdooccur,thetemperaturewhichthegateaureachshould
bekeptaslowaspossible.
Furtherreading
Cauvain,S.,Young,L.,2008.BakeryFoodManufactureandQuality:WaterControlandEffect,
seconded.Wiley-Blackwell,Oxford,UK.
OtherBakeryProducts
Chapter|8
409
8.33WEHAVERECENTLYBEENEXPERIENCINGWEEPING
FROMOURNON-DAIRYCREAMFORMULATION.
THISSHOWSITSELFASASOGGYLAYERWHERETHECREAM
ISINCONTACTWITHTHECAKE.CANYOUPLEASEADVISE
ONHOWTOCURETHEPROBLEM?
Tosolveyourparticularproblem,wefirsthavetodecideitsorigins.There
arethreepossibilities;fat,moisturemigrationorboth.
Fatmigrationcanoccurwhentheoilfractionofthecreamfillingistoo
largebecauseitdoesnotremaintrappedwithinthecreamstructureandsinks
intothecakelayerbelowundertheinfluenceofgravity.Todecidetheoilto
solidfatratio,youwillhavetoconsideranumberoffactorsincluding:

Theproductstoragetemperature,thehigherthestoragetemperaturethe
higherthesolidfatindexneedstobe.

Theeatingqualitiesofthecream,thesoftertheeatingcharacterthe
greatertheliquidoilfractionwillhavetobe.
Fatmigrationisnotparticularlyinfluencedbystoragehumiditybutis
affectedbystoragetemperature(see
Fig.8.2
);thehigherthestoragetemper-
ature,thegreatertheproportionofagivenfatthatisliquidandsothegreater
theriskofseepage.Fatseepageisalsoaffectedbythedegreetowhichthe
creamhasbeenaeratedwithseepagebeinggreaterasthecreamspecificvol-
umeincrease.Youmaywishtolimityourcreamspecificvolumeorreduce
youroverallfatcontent.Toreducefatseparation,youmayfindsomeadvan-
tageinaddingasuitableemulsifiertothecreamformulation,e.g.,lecithinor
glycerolmonostearate,orastabiliserlikegelatine.
FIGURE8.2
Fatandmoistureseepageinnondairycreamcakes.
410
BakingProblemsSolved
Moisturemigrationoccurswhenthewateractivityofthecreamisnotin
equilibriumwiththatofthecake.Thecausesandcuresformoisturemigration
havebeenreviewedby
CauvainandYoung(2008)
.Yourproblemisassoci-
atedwithmoisturemigrationbydiffusion,thatis,wheretwomaterialsarein
directcontactwithunequalwateractivitiesthemoisturemovesfromthewet-
tertothedriercomponent.Themainsolutiontotheproblemofmoisture
migrationistobalancethecomponentwateractivitiesandreducethedriving
forceforchange.Thiswillrequireareformulationofcream,cakeorboth.
Youshouldhavethecomponentwateractivitiesmeasuredandreformulateto
reduceanydifferential.Adjustingsaltorsugarlevelscanbeadvantageous,or
additionsofglycerolmaybeused.Placingamoisture-proofbarrierbetween
thetwocomponentsispossiblebutdifficultgiventheporousnatureofcakes.
Moisturemigrationisalsostronglyinfluencedbythestoragetemperature,
withmigrationbeingreducedasthestorageislowered.Unlikefatmigration,
moisturemigrationisaffectedbystoragehumiditywithmigrationmovingat
storagehumidities.
Reference
Cauvain,S.P.,Young,L.S.,2008.BakeryFoodManufactureandQuality:WaterControland
Effects,seconded.BlackwellScience,Oxford,UK.
OtherBakeryProducts
Chapter|8
411
8.34HOWCANWEPREVENTOURAPPLEPIEFILLING
GOINGMOULDYWITHINAFEWDAYSWITHOUT
CHANGINGTHEFILLINGRECIPE?
Ifyoudonotwanttoaltertheeatingqualityoftheapplepiefillingtheeasi-
estcourseofactionistoaddapreservative.Forexample,adding150ppm
potassiumsorbate(onaweightbasis)tothefillingshouldextenditsmould-
freeshelf-lifeto7or8days.However,forsmallbatchesofabout3.5kg,the
quantityofsorbateinvolvedisonlyabout0.53g.Theeasiestwayofadding
suchasmallquantityofpreservativewouldbeforyoutomakeupabulk
mixofsugarandpotassiumsorbate.Forarecipewith0.5kgsugarper3.5kg
batchoffilling,each0.5kgofsugarinthebulkmixshouldcontain0.53g
sorbate.Thus,ifyoumakeup12.5kg(28lb)ofbulkmix,itshouldcontain
13g(0.5oz)ofpotassiumsorbate.Itisessentialthatyoumixthesugarand
thesorbateverythoroughly,forexamplebymixingatlowspeedforatleast
0.5hour.Youcouldthenweighoffappropriateportionsofthemixforeach
freshbatchoffilling.
BakingProblemsSolved
8.35INSOMEOFOURAPPLEPIES,WEFINDTHATTHE
FILLINGHASTURNEDBLUE.WHYSHOULDTHISHAPPEN?
Thebluediscolourationinyourapplepiefillingisprobablycausedbyanat-
uralpigment.Naturalpigmentsfromblackcurrants,blackgrapeskinsand
someflowerssuchasdahlias,lobeliasandMichaelmasdaisiescontainantho-
cyanins.Themostprobableexplanationofthecolorationonyourapplepie
fillingisthatithascomefromutensilsormachinerythathadpreviously
beenusedforblackcurrantfilling.Ifthesameutensilsarebeingemployed
Chapter|8
8.36CANYOUSUGGESTASOLUTIONTOTHEPROBLEM
OFSHRINKAGEINOURAPPLEPIEFILLING?
Themainproblemwithshrinkageofapplepiefillingsarisesthroughthe
lossofwater,eitherduringbakingorsubsequentstorage.Insomecases,
thiswillbebecausetheERHofthefillingistoohighandyoumayneed
toloweritbyaddingsomemoresugar,orothersuitablesolublematerial,
e.g.,dextrose.
Theotherpossiblereasonfortheproblemarisesfromthephysical
breakdownofthefruit,pulping,whi
chresultsinlossoffillingvolume.
Bramleyapplesaregenerallyconsideredtobethemostsatisfactorytype
ofappleforbakingpurposes.Itispossible,however,thatwell-matured
fruitwhichhasundergonecanningmaynotbeabletowithstandbaking
aswellaslessmaturefruitwouldinarelativelyfreshcondition.You
maywishtotryusingfreshapplewhichhasbeenpreservedinascorbic
acidorbrine.
CHARACTERISTICSURFACEHOLES?
isdepositedontothehotplateandcarbondioxidewhichisdissolvedinthe
batterisquicklydrivenoutofsolution.Theevolutionofthecarbondioxide
commonlydescribedasbeingblind.
Thephenomenonismostcommonlycausedbydraughtsblowing
baking.Theproblemmayalsobecausedbyexcessgreaseontheinside
oftheringsintowhichtheindividual
portionsofbatteraredepositedor
adepositweight.
Ifyoutakestepstoreducedraughtsandcontrolgreasingandstillhave
theproblemthenyoumayfindithelpfultohaveaminimumfermentation
timeof1hbeforedepositingthebattertomakesurethatthebatteriswell
aerated.Duringdepositing,youneedtoavoiddegassingofthebatteras
muchaspossible.
inallowingwillallowingmoreofthecarbondioxidegastoescapeduring
bakingonthehotplate.Itishelpfultolimitglutenformationinthebatter
terscancontributetotheformationofglutenasthebatterissubjectedto
shearinthepipework.Itisimportanttomaintainviscosityofthebatteras
thishelpstheformationoftheholesonthehotplate.
Thismaybedifficultwithlowerproteinfloursbutthereplacementof
partoftheflourwithachlorinated(see
Section2.2.18
)orheat-treatedflour
(see
Section2.2.17
)maybehelpful.Boththechlorinatedandheat-treated
flourswillabsorbmorewaterthananon-treatedflourandsoraisebattervis-
cosity.Theaimwouldbetoslowdowntheverticalmovementofthecarbon
dioxidegasasitisdrivenoutofsolutiononthehotplate.
OtherBakeryProducts
Chapter|8
415
8.38WHYISASMALLAMOUNTOFBICARBONATEOF
8.39THECHOCOLATECOATINGONOURMARSHMALLOW
TEACAKESCRACKSDURINGSTORAGE.CANYOUOFFER
ANEXPLANATIONANDSOLUTIONTOTHEPROBLEM?
Thecauseofthisproblemiseasytoe
xplainbutrathermoredifficultto
eradicate.Amarshmallowteacakeisacompositeproductmadeupofa
biscuitbase,marshmallowtoppingandchocolatecoating.Eachofthese
componentshasadifferentERH.Moisturewillmovefromonecompo-
nenttoanotherdrivenmainlybytherelativedifferencesinwateractivity
BiscuitshavealowERHandwillreadilyabsorbmoisturefromthe
atmosphereandbecomesoft.Whenmarshmallowisdepositedontothebis-
cuitmoisturefromthe,higherERHmallowwillmovetothebiscuitandas
aresultthebiscuitexpandsorswells(
CauvainandYoung,2008
).Thisnor-
mallyoccursafterthechocolatecoatinghasdried,andtheoveralleffectis
tocrackthechocolatecoatingwhichisnotextensibleenoughtotakeupthe
increaseinsize.
Toovercomethiscracking:

Thebiscuitmustnotbeallowedtoabsorbmoisturefromthemallow.
Youcouldtrysprayingthesurfaceofthebiscuitwhencoolwithmelted

Ideally,thebiscuitshouldhaveanERHsimilartothatofthemallow.
ThiscanbeachievedincreasingtheERHofthebiscuitorbydecreasing
theERHofthemallowbymodificationstotheformulations.Spraying
thebiscuitshortlyafterbakingwithwater,usingafinenozzle,orstorage
inamoistatmosphereforabout12hoursbeforedepositingandenrobing
shouldincreasetheERHofthebiscuit.Forthemarshmallow,replacing
someofthesugarbyglucosewilldecreaseitsERHandenableittohold
ontoitsmoisture.Usingoneoftheseremediesoracombinationthe
moisturemigrationfrommallowtobiscuitshouldbereduced.
Reference
Cauvain,S.P.,Young,L.S.,2008.BakeryFoodManufacture&Quality:WaterControland
Effects,seconded.Wiley-Blackwell,Oxford,UK.
OtherBakeryProducts
Chapter|8
417
8.40WHATCAUSESTHEWHITEBLOOMWHICH
8.41THEBAKERSCHOCOLATECOATINGWEUSEHAS
RECENTLYTENDEDTOFLAKEOFFOURECLAIRS.
CANYOUIDENTIFYALIKELYCAUSEOFTHEPROBLEM?
Allchocolatecoatingsshouldbecorrectlytemperedtoavoidproblems.
Generally,bakerscompoundchocolateshouldfirstbeheatedto54
F)forplainor52
C(125
F)formilkandthenallowedtocoolto
coatingconsistency.Thenecessarytemperaturesareabout41
F)forplainand38
C(100
F)formilk.
Ifthechocolateisnotmaintainedataconstanttemperature,theremaybe
Chapter|8
8.42WHATISGANACHE?
Ganacheisthenamegiventoablendofchocolateandcream.Toprepareit,
1kggratedcouvertureisplacedinastainlesssteelbowl.Overthisispoured
1Lboiling,freshcreamandthemixtureisstirred.Theheatoftheboiling
creammeltsthecouvertureandthetwoamalgamatetoformasmoothpaste.
Thisshouldbestirredoccasionallyuntilitiscool.
Ganachetakesmanyformsandisusedinmanyways.Ascreamis
8.43WHATARESTAFFORDSHIREOATCAKESANDHOW
ARETHEYMADE?
Staffordshireisaregion(county)inthemidlandsofEnglandandtheoat-
cakeinquestionisaregionalproduct.TheStaffordshireoatcakeshould
notbeconfusedwiththeScottishOatcakewhichisabiscuit(cookie).
Bothproductsuseoatmealasoneoftheiressentialingredients,butthe
finalproductsareverydifferent.TheStaffordshireoatcakeappearsto
datefromthe19thcenturywhentheywerebakedonahotplateoveran
openfire.
Thereareanumberofvariationsontherecipebutatypicaloneisas
follows:
IngredientPartsbyweight
Water100
Strongflour30
Fineoatmeal13
Salt1.0
Skimmedmilkpowder1.0
Yeast0.3
Bicarbonateofsoda0.3
Asshownbytherecipeabove,theoatcakesaremadefromavery
fluidbatter.Blendthedryingredients,exceptfortheyeastandthebicar-
bonateofsoda.Dispersetheyeastinabouttwo-thirdsofthewatermass,
addthemixturetothedryingredientsandmixtoalump-free,smooth
batter(about5
Chapter|8
8.44WHATAREFARLSANDHOWARETHEYMADE?
Farlsareatraditionalchemicallyaerate
dorsoda-breadoriginatingfromIreland.
Theyaremadeintwomainforms;whiteandwheaten,thelatterbeingbasedon
abrownflour(ablendofwhiteflourandb
ran)whichwastrad
itionallyreferred
toaswheatmealtodistinguishitfrom
wholemeal(thetermwheatmealisnow
largelyredundantintheUni
tedKingdomandelsewhere).
Traditionalrecipeswouldbeasfollows:
Wheatenfarl(basedon100partsbrownflour)
Brownflour100.0
Salt1.7
Maltflour2.3
Bakingpowder6.8
Fat18.0
Sugar13.6
Bran4.5
Whiteflour36.0
Milk90.0
Mixtoacleardough.Youadjustthemilktogiveasmooth,easilyhan-
dleddough.Scaleunitsat1kg,mouldround,flattenslightlywitharolling
pinandcutintofourquarters.Brushthetopwithwaterandsprinkleon
somebrownflour.Bakeataround230
Cfor15minutes.
Whitefarls(basedon100partsofwhiteflour)
Flour100.0
Bakingpowder3.1
Salt1.6
Maltflour2.0
Fat4.2
Milk70.0
Processasforwheatenfarls.
Somerecipessuggesttheadditionofasmalllevelofyeast,aroundfour
partstoboostvolume.Buttermilkmaybeusedtoreplacemilkifamoredis-
tinctiveflavouredproductisrequired.
BakingProblemsSolved
8.45THEEDGESOFOURSODAFARLSBECOMEGUMMY
ACOUPLEOFDAYSAFTERBAKING.WHATISTHECAUSE
OFTHISQUALITYDEFECT?
Adarkgummyseamonthesideoffarlsisgenerallycausedbyinadequate
baking.Thiscouldbedueto:
1.
Thetemperatureofthehotplatebeingalittlehigherthannormal,caus-
ingthefarlstobereadyforturning
soonerthantheyshouldbeandthe
farlbeingremovedfromthehot-plate
slightlysoonerthanusualtopre-
ventthesurfacebeingscorched.Thiswouldmeanthatthecentreis
inadequatelybakedandtendstocol
lapseduringcooling,producingthe
darkseams.
2.
Itispossiblethatifthecentreofthefarlneverreachedatemperature
highenoughtoinactivatetheamylaseenzymesintheflour.Thelatter
maystillbeactiveinthebakedproductthoughitisunlikelythatthisis
thecauseofthefaultunlessyouhavebacterialamylasepresent.You
shouldchecktheFallingNumber(see
Section2.2.10
)ofyourfloursand
avoidoneswithlowFallingNumbers(high
alpha
-amylase).
3.
Thewaterabsorbingcapacityoftheflourmayhaveincreased,requiring
theinclusionofmorewateratdoughmixing.Inthiscase,theproduct
mayneedslightlylongerandcoolerbakingconditionsthannormalto
driveofftheadditionalwater.
OtherBakeryProducts
Chapter|8
423
8.46WEWANTTOADDFRESHLYBAKEDDEEP-PAN
PIZZATOTHEPRODUCTRANGETHATWESELLTHROUGH
OURBAKERYSHOP.WEDONOTWANTTOMAKESMALL
QUANTITIESOFDOUGHTHROUGHOUTTHEDAYFOR
THEIRMANUFACTURE,BUTWHENWETRYTOWORKWITH
ALARGERBULKOFDOUGH,WEFINDTHATTHE
VARIATIONINQUALITYISTOOGREAT,EVENWHENWE
WOULDBEASUITABLEWAYFORUSTOMAKETHEBASES?
Onewayofspreadingyourpizzaproductionthroughoutthedayistomakea
largerdoughwhichyousplitupaftermixingandprocessintopizzabase
shapesreadyforproof.Youwillneedtohaveareasonablenumberofpans
available.Preferably,theseshouldbeoneswhichyoucanstackoneinside
another,butifyoudonothavethistypeavailable,thenyoucanuseaseriesin
youstackothersontop.Themethodthatwearegoingtosuggestrequiresyou
tohaveaccesstobothaproverandaretarder(thoughnotatthesametime)
andyouwillneedtobeabletofittheproductionintoyourexistingproduction
planortobeabletomodifyittoaccommodatethenewproduction.
Afteryouhavepreparedthebasesandloadedthemintothepans,you
shouldputthemintotheprover;wesuggestthatyouusetemperaturesinthe
regionof25

35

Candcertainlynohigher.Dependingonyouryeastlevel,
youwillneedtogivethedoughpieces1

2-hproofanditisimportantto
maintainareasonablehumiditylevel,sayaround70%.Youcanstackthe
pansforproofifyouwishthoughitisnotcriticalatthisstage,italldepends
onhowmuchspacethatyouhaveavailable.
forcoolingandstorage.Theretardertemperatureshouldbeintherange
2
3

C
to
1
3

C,andyoushouldstackthepansontopofoneanothertokeepthe
humidityhighenoughtopreventskinning.Whenyouneedbasesforbakingyou
eadonthetomatosauceaddthetopping
andtransfertotheovenforbaking.Theprovedpizzabasescoolquicklyin
limitsanyfurthergasproductionbutth
baseswhichcanbeturnedintothebakedproductinafewminutes.
Asyouareusingmetalpans,youneedtomakesurethattheyremainin
(see
Section4.2.13
)thoughprobablytheretardedstoragetimeistooshortfor
thistobeanissue.Youmayfindithelpfultohavesomesmallholesinthe
baseofyourpanstoallowtrappedsteamtoescapeandavoidblistersandhol-
lowsonthebase(see
Section4.1.1
).
424
BakingProblemsSolved
8.47WEFREEZEOURUNBAKEDPIZZABASESINA
NITROGENTUNNEL.ONDEFROSTINGANDBAKING,
Chapter|8
8.48WHATARETHEKEYCHARACTERISTICSOFCAKE
DOUGHNUTSANDHOWDOTHEYDIFFERFROMOTHER
TYPESOFDOUGHNUT?
Thetwomainclassesofdoughnutsarethosebasedonmakingalowviscosity
cakebatterandafermenteddough.Thecakedoughnutismadebydepositing
thebatterdirectlyintothehotoilforfrying.Themostcommonformofcake
doughnutisring-shaped,andtheyareoftentoppedwithacolouredand
flavouredicingorglaze(see
Fig.8.3
).Themostcommonformofthefermen-
teddoughnutisballorfingershapewithajamorjellyinjectedintotheshape
andtheoutersurfacedustedwithfinesugarcrystals.
Informulationterms,cakedoughnutstendtohaveahighersugarlevel
thanfermentedformsandusebakingpowderasthesoleaeratingagent.
Overallcakedoughnutstendtobedenserandhavealesswell-definedcellu-
larstructurethanfermenteddoughnuts;theeatingqualitiesaredistinctly
cake-likewithalesschewyeatingcharacter.
Thechoiceofflourisimportantforthemanufactureofcakedoughnuts,
anditiscommonpracticetousealowerproteinflourthanwithfermented
doughnuts.Sometimes,amixtureofstandardandmodifiedfloursmay
beused.Inthecaseofthemodifiedflour,itmayhaveareducedparticle
size(see
Section2.2.16
)orsomepost-millingtreatment;i.e.,heattreatment
(see
Section2.2.17
)orchlorination(see
Section2.2.18
)inthosepartsofthe
worldinwhichitsuseasaflour-treatmentagentarestillpermitted.
Itisimportanttocontrolthereleaseofcarbondioxidegasbythebaking
powderreactionincakedoughnuts.Thegenerationofcarbondioxideisnotonly
partoftheexpansionmechanismbutisalsopartofthemeansofcontrollingthe
degreeoffatabsorptionduringfrying.Thepressurefromtheexpandinggases
preventstheabsorptionoffataslongasthegascellsinthedoughareintact(see
Section4.2.1
).Ifthecarbondioxideisreleasedtoosoonduringfrying,thefinal
productlacksvolumeandhasadenseandfattyeatingcharacter.Ifthecarbon
dioxideisreleasedtoolate,thentheproductwilloftenhaveadistortedshape.
Furtherreading
).
FIGURE8.3
Doughnuttypes:Left,fermented;right,cake.
426
BakingProblemsSolved
8.49WEHAVEBEENPRODUCINGARANGEOFCAKE
DOUGHNUTSWHICHAREICEDWITHVARIOUS
FLAVOUREDCOATINGS.TOCOPEWITHPEAKDEMANDS,
WEHAVETAKENTOFREEZINGAQUANTITYOFTHE
PRODUCTS.WEHAVEOBSERVEDTHATPROGRESSIVELY
DURINGSTORAGEACRYSTALLINEGROWTHAPPEARSON
THEPRODUCTS.WHENTHEYAREDEFROSTEDTHEGROWTH
DISAPPEARS.CANYOUIDENTIFYWHYTHISHAPPENS?
Thegrowthsthatyouaredescribingaremostlikelytotheformationof
sucrosehydrateonthesurfaceoftheicing(
CauvainandYoung,2008
).
Duringthefreezingoftheiceddoughnuts,freeze

concentrationcanoccur
intheicing.Thepresenceofahighlevelofsugarsintheicingsconsiderably
depressesthefreezingpointofthemixtureofsugarandwater.Asthetem-
peraturebeginstofallsomeofthewaterintheicingformsicecrystalandis
nolongeravailabletokeepthesugarsinsolution,theconcentrationofthe
remainingsugarsolutionisincreasedandthefreezingpointisfurther
depressed.Thiscycleofactioncontinuesuntilthetemperatureofthefreezer
isreached.
Intheicing,therearetwoprocessestakingplace.Oneiscrystalnucle-
ationandthesecondiscrystallinegrowthorpropagation.Nucleationisthe
mentforcrystalgrowth.However,forcrystalgrowthtooccur,thesugar
moleculesmustbesufficientlymobiletoaggregate.Thefreeze

concentra-
tioneffecttakingplaceintheicingprobablymeansthatthereisaconcen-
tratedandunfrozensugarsolutionevenwhentheproductsareplacedinto
storageat
2
20

Candsothepotentialisthereforcrystalgrowthtooccur.
First,wesuggestthatyoulookcloselyatyourinitialfreezingandfrozen
storageregimes.Trytomakesurethatthetemperaturetowhichyoufirst
freezeyourproductsisascloseaspossibletothatatwhichtheywillbe
asshortaspossibleandminimiseanyopportunitiesformoisturelosses
beforeover-wrapping.
Thistypeofproblemisexacerbatedbyanyperiodsofdefrostingand
refreezingduringstoragebecausetherateatwhichtheproductswillrefreeze
instoragewillbeconsiderablylowerthanusedinitiallyforfreezingthe
product.Aslowreductionintemperaturefavourscrystalgrowthandthe
Whilethegrowthsmaydisappearondefrostingitisnotunusualtobeleft
withlocalisedwhitespots,pittingandstreakingontheicingsurface.You
cantryreformulatingtheicingbyaddingmoreglucose(see
Section8.16
).
OtherBakeryProducts
Chapter|8
427
Reference
Cauvain,S.P.,Young,L.S.,2008.BakeryFoodManufactureandQuality:WaterControland
Effects,seconded.Wiley-Blackwell,Oxford,UK.
Furtherreading
).
428
BakingProblemsSolved
8.50AFTERASHORTPERIODOFCHILLEDSTORAGE,
WEOBSERVECRATER-LIKECRYSTALLINEFORMATIONS
ONOURCHEESECAKETOPPING.DOYOUKNOW
WHYTHISOCCURS?
Crater-likecrystalformationsinfondanttypetoppingsareconsistentwith
theformationofsucrosehydrate(
CauvainandYoung,2008
).Localised
whitespotsorstreaksaretheresultoftheformationofsugarcrystalslarger
thanthosepresentinthemassoffondant.Thepresenceofmaterialswhich
mightcausethefondanttoseedandformsugarcrystalswhichthengrow
accentuatestheproblem.
thefondant.Theinclusionofglucosesyrupinthesimplesyrupformusedfor
thinningthefondantmaypreventthisseeding.Atypicalrecipeforsuchsyrupis:
Water1.25L2pt
Sugar1.5kg3lb
Glucose250g8oz
Theingredientsarebroughttotheboilandallowedtocoolbeforeuse.
Careshouldbetakenthatthefondan
tistemperedcorrectlyandnot
overheated(i.e.,notabove43

C)duringpreparation.Preparationtanks
shouldbeinspectedtocheckthatacrustofhardenedfondanthasnot
formedroundtherimasthiscanactasasourceofseedcrystalsforsugar
crystallisation.Similarly,anysuperf
luousicingsugarorothermaterialcan
causethefondanttoseedandformsug
arcrystals.Minimisingmoisture
lossfromtheproductcanalsoalleviat
etheproblembypreventingtheloca-
lisedsugarconcentrationreachingthepoi
ntwhererecrystallisationislikely
tooccur.
Youneedtobecarefulwhenrecyclingscrapsoficingbackintothemix
asthesewillhavedriedoutandactasanothersourceofseedcrystals.Itis
naturaltowanttorecycleicingscraps,buttheseshouldbedonefrequently
useinthenextbatchoficing.
Pitting,grainingandevenbubblesandblistersonthesurfaceoficed
ofosmophilicyeastswhicharecapable
offermentingtheicingandgenerat-
ingcarbondioxidegas;thelatteristhesourceofthebubblesandblister.
Fromahygieneviewpoint,cleaning
allsurfacesthatcomeintocontact
withsuchcoatings,includingallves
selsusedtoholdortransportthem,the
OtherBakeryProducts
Chapter|8
429
bain-marie,allworkingsurfaces,sm
allcontainersandutensils,canmini-
misetheuptakeofspoilageorganism
sandmaterialswhichmightcause
seedinglater.Onceagaintherecyc
lingofleftovermaterialsisusedis
oftenthesourceofsuchproblemsbeca
useviableyeastcellsmayremainin
theproduct.
Reference
Cauvain,S.P.,Young,L.S.,2008.BakeryFoodManufacture&Quality:WaterControland
Effects,seconded.Wiley-Blackwell,Oxford,UK.
430
BakingProblemsSolved
8.51WEWANTTOEXTENDTHEMOULD-FREESHELF-LIFEOF
OURFLOURTORTILLA(
FIG.8.4
)BUTWHENWETRYTHE
DOUGHMOREACIDWEHAVEPROCESSINGPROBLEMS.WHAT
OPTIONSCOULDWECONSIDERFORACHIEVINGOURAIM?
Acidifyingthedoughissufficient
forinhibitingthedevelopmentofrope
(see
Section4.1.4
)andisacommonwaytoextendmould-freeshelf-life,
especiallywhentherearepreservativespresentintherecipe.Themagni-
tudeofthecombinedeffectdependsontheparticularpairingused.The
combinationofpotassiumsorbateandanacidismoreeffectiveasananti-
mouldagentthanusingcalciumpropi
onateandacid.Usually,youwould
usepotassiumsorbateasananti-moul
dpreservativeinthemanufactureof
cakesbutnotinfermentedproductsbecauseoftheinhibitingeffectthatit
hasonyeastactivity.Asyourproduct
sarepowder-raised,thenitisper-
fectlypossibletousepotassiumsorbate.
LoweringthepHofthedoughhasaneffectonitsrheologicalproper-
tiesandthisisthereasonforsomeofyourprocessingproblems.Atlow
pHs,theelasticityofthedoughoftenincreasesandthiscanmakeshaping
moredifficult.Onewayaroundthisproblemwouldbetouseanencapsu-
latedacidwhichhasnosignificanteffectindoughmixingandprocessing.
Fatisnormallyusedastheencapsulatingagent,andintheoven,the
fatwillmeltreleasingtheacid.Inthisform,theacidisstilleffectiveat
servativeandlowpH.
Anotherwayoflengtheningtheproductmould-freeshelf-lifeisbylower-
ingthewateractivityoftheproduct.Onceagain,thecombinationoflower
wateractivityandpotassiumsorbateismoreeffectivethaneitherapproach
onitsown.Anotherwaytolowerthewateractivitywouldbebyadding
glycerolorsomeotherpolyol(seechapter:Whatarepolyolsandhoware
theyusedinbaking?).
FIGURE8.4
Flourtortilla.
OtherBakeryProducts
Chapter|8
431
8.52WHATARETHEORIGINSOFPAPPADAMS?
Pappadamsarelikeextra-largecrispsandareanaccompanimentforAsian
foods(
Fig.8.5
).Alternativenamesarepapadams,puppodums,appalanand
papad.Papadsareroughlyround,thedimensionsvaryingaccordingtowhere
thepapadismanufactured.Mostfallwithinthefollowingdimensions:

10to18cm;thickness

0.5mmto1.5mm;weight

4to24g.
15g.Thecolourofthepapaddependsonthetypeandqualityofflourand
otheringredientsused.Thecolourcanbeyellowishwhitetoyellowishbrown.
Papadsareeatenwithanytypeofmealorasasnack.Oneortwoper
mealperpersonisusualbutaswithmanyfoodsitdependsonpersonaltaste.
Papadsareeatenafterfryingforafewsecondsinoil,orgrillingormicro-
waving.Whenfriedinoiltheyexpandbyabout30

40%.Aftertheheating
process,thepapadbecomescrispandbrittle.
Abasicrecipeis:

100partsblackgramflour

45partswater(variable)

8partssalt

1partsodiumcarbonateor1.0

1.5partssodiumbicarbonate
Theflourisobtainedbymillingapulse(bean)knownas
Phaseolus
mungo
15oblong-shapedseeds,3to4-mmlongand2to3-mmwide.Thepodsare
driedunderthesun,theseedstakenout,theirhusksremovedandthebean
FIGURE8.5
Flatbreads(topright,pappadams;left,kebabbread;bottomright,chapattis).
432
BakingProblemsSolved
Chapter|8
8.53WHATISKEBABBREAD?
KebabbreadisthewesternEuropeannamefortheMiddleEasternbread
knownaspittaorkhubz(
Fig.8.5
).Thistypeofbreadhasbeenpopularised
byGreek-Cypriotrestaurantswhoservethebreadwithshishkebabs.
practice.
kg
Flour100
Yeast0.7
Salt2.5
Water(fairlysoftdough)57
Theflourusediswhite,untreated,unbleachedandlowinprotein.The
doughismixedonalowspeedmixerforabout20mintoadoughtempera-
ture27

28

C.After45minthedoughisscaledinto150g(5oz)pieces,
mouldedround,restedfor10minandthenpinnedtogiveathinflatoval
shapeabout24

25-cmlongandabout11-cmwide.Theovaldoughis
316

C(600

F)forabout5min.
Followingbaking,thepittasmustbecooledforabout10min,afterwhich
theycanbestackedup.Thebreadsmaybeputintopolythenebagsonce
theyarecoolenoughtokeepthemsoftandflexible.Theycanbereheated
underawarmgrillbeforeserving.
Itisessentialtouseuntreatedflourastreatedbreadflouryieldspittas
andbottomsurfaces.
434
BakingProblemsSolved
8.54WHATISBALADYBREAD?
BaladybreadisanEgyptianbreadproductbasedonasourdoughorstarter
system.Thestarterdoughisusedtoprovideflavourratherthanforleavening
purposes.Thebreadisround,flat,puffsupduringbakingandiseasilysepa-
ratedintotwolayers.Theflourblendnormallyusedforthisproductis
30%strongflourof72%extractionand75
70%Egyptianflourof82%
extraction.
Recipeforstarter
11kgolddough
100kgflour
50kgwater
Compressedyeastmaybeaddedincoolerweather.Thestarterdoughis
fermentedforatleast3hours.Thefermentationperiodmaybelonger,
dependingonhowsoonthestarterisrequiredforuse.
Recipeforsimplestraightdough
100kgflour
75Lwater
0.7kgsalt
15kgstarterdough
Theingredientsaremixedfor20
25mintoproduceaslackdough(not
fullydeveloped)whichisthenimmediatelyscaledinto180gdoughpieces.
Thedoughpiecesaremouldedintoroundshapes,placedontraysandsprin-
kledwithbran.Intermediateprooflastsfor15min.Thedoughpiecesare
Chapter|8
8.55HOWARECHAPATTISMADE?
ChapattisareabakedproductrelatedtobreadandoriginateinAsia,where
theyareeatenwithalmosteverymainmeal.Traditionally,chapattisare
madefreshforeachmealandareroughlyroundinshape(see
Fig.8.5
),with
Agreatdealofvariationinsizeandformulationoccursdependingonper-
sonalpreference.
Typicalrecipe
Flour1kg
Water650to750g
Wheatflourisusedtomakechapattis.Theextractionratecanbeanything
saltandfataddedaccordingtopersonaltaste.Therecipedoesnotcontain
yeast.Thedough,whichisfairlyfirm,isrestedforupto30minbeforebeing
scaledintoportionsweighing30

85g.Theseareroundedintoballs.Afur-
therrestisdesirablebeforerollingtheballsintothindiscs1

3-mmthick.
Therolledoutchapattisarecookedonbothsidesusingahotplateata
temperatureof233

260

C(450

500

F).Cookingtimewilldependonthe
thicknessandcontinuesuntilthechapattisstarttoblisteronbothsidesand
thecolourisjustturningbrown.Thisstagetakesapproximately0

5min
foreachside.Chapattismaybeeatenafterthisstagehasbeenreachedor
theymayreceiveasecondbakingcalledpuffing.Inthepuffingprocess,
whichtakesjustafewseconds,achapattiisplacedunderagrillorovera
red-hotfireanditimmediatelypuffsupintoaball.Assoonasithaspuffed,
itmustbetakenawayfromthegrillorfireasitwillburn.Atthisstage,the
chapattiiscomposedoftwolayersofskinswithaspacebetween.Puffing
israrelycarriedoutonchapattiswhicharemorethan2mmthickasthey
donotpuffwell.
Afterpuffing,thechapattiscollapsebacktotheoriginalshape,andthey
shouldbestackedoneontopoftheothertoavoiddryingout.Toprevent
practicewhichhastheaddedadvantageofmakingthemsoftandimpartinga
butteryflavour.Thefinalchapattiswillvaryincolouraccordingtothetype
andextractionrateofflourused,butalmostallwillhavebrownblisters,
someofthemslightlyburnt.Ifchapattisarestoredaftercookingformore
thanafewhours,theytendtosticktogetherandlosetheirattractiveeating
characteristics.Stalechapattiscanbeimprovedbyre-heatingbuttheydonot
regaintheiroriginalquality.
436
BakingProblemsSolved
8.56WHATARECORN(MAIZE)TORTILLAS?AND
HOWARETHEYMADE?
Thecorn(maize)tortillaisanon-fermentedproductmadefrommaizeflour,
andisthebasisformanytraditionalMexicandishes.Theyaremadeonhot-
plategoodsandhaveasimplerecipe.
Wholemaizeflour100
Water33
Lime
a
(calciumhydroxide)0.1
a
Thelimemustbesuitableforuseinfoodandcomplywithlocalfoodlegislation.
ThisrecipeuseswholemaizeflourwhichhasbeenpassedthroughaUS
40-meshsieve(screensize0.016in).Thetortilladough,knownas
masa
,is
thickandcookedonahotplateuntilbothsurfaceisslightlybrowned.
Tortillascanbeeatenalonelikebread,orfriedwithacheesetopping
(
nachos
).Apopularformisthe
taco
.Afterfryingthetortillacanbefilled
withmeat,tomato,cheese,olives,peppersandsauce.Alternativelythetorti-
llamaybesoftenedinoilorsauce,rolledroundameatorcheesefillingand
bakedtoproducean
enchilada
.
OtherBakeryProducts
Chapter|8
437
8.57WHATISTRENCHERBREADANDHOWWASITUSED?
Itisbelievedthattrencherbreadwasfirstmentionedin15thcenturybooks
David,1977
)thoughitsoriginsarelikelytobemuchearlier
thanthereferencessuggest.Trencherswereessentiallycoarseslicesofbread,
fromloavestypically4daysold,usedinsteadofaplateatamedievalmeal.
Afterthetrencherhadserveditspurposeasaplateandhadbeensaturated
bythesaucesandjuicesofthemeallaiduponit,itwaseatenbytheservant,
cutupforthepoororgiventothedogs.
Trencherbreadwasmadefromcoar
selymilledflourwhichprobably
comprisedsomewholemeal(wheat)flourmixedwithsomewholebarley
orryeflour.Thewholemealflourmayhavebeensievedtoremovethe
nobilityintheMedievalperiod.Thecoarseflourwasmadeupintolarge,
flat,rounddenseloaveswhichwe
reprobablybakedinanoven,though
occasionally,theywerebakedonahotplate.Theloafwasprobablyturned
halfwaythroughbakingtogivetwoflat,firmcrustsandanevenlayerof
crumb.
Thetrencherloaveswerestoredfor4daysandthenpreparedbytheser-
vantusingaspecialknifeforthepurpose.(Theuppercrustwasdestinedto
bethenoblemansplateandmaywellbetheoriginsofthephraseupper
crust.)Itisbelievedthatthetopandbottomcrustswereremoved,along
withthesidecrustsleavingasquare,crustlessloafabout2to3-cmhigh.
Thisloafwasthenmadeintooneortwosquareplatesonwhichaserving
ofmeatcouldbeplaced.Inlaterperiodsthetrencherbreadwasreplacedby
woodenorpewterplatters.
g/Mixlb/Sack
Wholemealflour1120186.5
Wholebarleyflour56093.5
Salt244
Yeast122
Water1140mL190
Mixthedoughontwinarmlowspeedmixerforabout20minutesand
thenfermentinbulkforhalfanhour.Scaledoughpiecesto1.8kg(4lb),
438
BakingProblemsSolved
mouldintoaball,restfor10minutesandpinouttodiscs267mm(10.5in)
andbakefor45mininanovenat204

C(400

F).Oncecoolwraptheloaf
inateatowelandstorefor4days.Onthefourthday,cuttheloafinthecor-
rectwaytogiveoneormoretrenchers.
Reference
David,E.,1977.EnglishBreadandYeastCookery.AllenLanePenguinBooksLtd,London,
UK.
OtherBakeryProducts
Chapter|8
439
8.58WHATISTHEPRODUCTKNOWNASAGRANTLOAF?
TheGrantwholemealloafisonerecommendedby
DorisGrant(1944)
.
Granthadtaughthouseholdreaderstomixandbakewholemealbreadbyan
Grantloafisnotoneintendedforcommercialproductionbutratherfor
Grant:

3.5lbEnglishstone-ground,wholemealflour

2pt4ozofwateratbloodheat(orslightlyless)

1ozsea-salt,Maldonsaltorordinarysalt

1ozsugar,preferablyBarbadosmuscovadocanesugar

1ozyeast(orupto4oz)

Mixthesaltwiththeflourinalargebasinandwarmit(make
lukewarm

nothot)ontheoventoporabovealowgasflame,sothatthe
yeastwillworkquicker.

Crumbletheyeastintoapuddingbasin,addthesugarandaquarterpint
oflukewarmwater.

Leavefor10minutestofrothup;thenstirtodissolvesugar.

Pourthisyeastyliquidintothebasinofwarmflour.Addtherestofthe
warmwater,anddosograduallyincaseallthewaterisnotrequired.

mixwellbyhandfor2minutes.


Greasethree2pttinsinsideandwarmthemwell.Turnthedoughintothe
ovenwhiletheoveniswarmingup),coverwithaclothandleavefor
about20mintorisebyaboutone-third.Bakeinanovenat205

C
(400

F)for45

60min.
Grantconsideredthatrealbreadshouldbemadefromwholewheat
grownonnaturallyfertilisedsoilandfreshlystone-ground(c.f.organic).She
identifiedthemostimportantproductionpointsasbeing:

Towarmtheflourandthebakingtins

Tofrothuptheyeastseparately


Torememberthatwholewheatdoughmustnotbekneadedandonly
requiresafewminutestomix.
440
BakingProblemsSolved
David(1977)
Wholemealflour1.6kg
Water1.25L
Salt30g
Sugar30g
Yeast30g(orupto120gforextrafoodvalue)
Margarineorbutter(optional)60g
Tinsize:Threeby1kgtins.
Bakingtemperature

205

C.
withmixingfor5minuteswithahouseholdmixer.Theresultantbreadwas
coarsestructuredwithfragilecrumbbutperfectlyacceptableforhome-made
bread.
References
David,E.,1977.EnglishBreadandYeastCookery.AllenLanePenguinBooksLtd,London,
UK.
Grant,D.,1944.YourDailyBread.Faber&Faber,UK.
OtherBakeryProducts
Chapter|8
441
Thispageintentionallyleftblank
Chapter9
ProcessesandEquipment
9.1ISEEMANYREFERENCESTONO-TIME
MEANANDWHATISITSRELEVANCE?
Thetermsno-timedough(NTD)orno-timedoughmakingprocessescover
awiderangeofoptionsofingredient,recipeandmixingcombinationsinthe
manufactureofbreadandfermentedproducts.Essentially,thetermrefersto
theprinciplethatthebulkdoughistransferredaftermixingtobedivided
withoutanysignificantordeliberatefermentationorrestingperiod.
Breadmakingprocesseswhichemployadeliberatefermentationphase
mentationprocesses,longfermentationprocesses(LFP),spongeanddough
orprocessesinvolvingfloortime.
ThepracticaladvantagesofusingaNTDareassociatedwithspace
saving

therearenolargebowlsofdoughstandingforlongperiodsoftime
inthebakery;improvedprocesscontrol

noriskoffermentingdoughsbeing
takenoutofsequencewithsubsequentnegativeeffectsonfinalproductquality
andinthecaseofplantbreakdown,noover-fermentingdoughtodealwith.
InadditionwithNTDs,therearenoneofthefermentationlossesassociated
withLFPswhichmayrunto2

3%ofthestartingrawmaterialsasaresultof
theprolongedfermentation.
Toachievetherequireddevelopmentofthedoughforprocessinginto
bread,itiscommontoaddfunctionalingredientswithNTDs.Themostcom-
moningredientaddedisascorbicacid,thoughenzymesofvarioustypes,
emulsifiers,fatsandreducingagentsmaybeusedatdifferentlevelsof
addition.
OftenrecipewaterlevelswillbehigherwithNTDsthanwithLFPssoas
toadjustdoughconsistencyfordividingandmoulding.Thisextrawateris
requiredtocompensateforthelackofdoughsofteningwhichoccursasthe
resultofenzymicactionovertheextendedprocesstimesassociatedwith
LFPs.Anotherimportantchangeistheadditionofextrayeastbycomparison
withLFPs.Thisistocompensatefortheintrinsicallylowergaslevelsinthe
doughatthetimeofdividingandensurethatfinalprooftimesarenotunduly
extendedbycomparisonwithLFPs.
443
BakingProblemsSolved.DOI:
http://dx.doi.org/10.1016/B978-0-08-100765-5.00009-6

2017ElsevierLtd.Allrightsreserved.
TheflavourprofileofbreadsmadeofNTDswillbedifferentfromthat
ofLFPsduetothelackofanextendedbulkfermentationstageandismore
affectedbylevelsofrecipeingredientssuchassalt,sugar,maltproductsand
inclusions.NTDsaresuitableforalltypesofbreadandfermentedproducts
andcanbeusedinbothlargeandsmallbakeries.Duetotheirconvenience
andtheirpotentialforgoodprocesscontrol,NTDsintheirformsprobably
accountforthegreatestproportionofbreadandfermentedproductsmanu-
facturedaroundtheworld.TheversatilityofNTDsmeansthattheycanbe
usedwithawiderangeofmixinganddoughprocessingequipment.
Furtherreading
Cauvain,S.P.,2015.TechnologyofBreadmaking,thirded.SpringerPublishingInternational
AG,Switzerland.
444
BakingProblemsSolved
9.2WEARECONSIDERINGTHEPURCHASEOFANEW
MIXERFORTHEMANUFACTUREOFOURBREADUSING
ANO-TIMEDOUGHPROCESS.THEREARETWOTYPESOF
MIXERWHICHSEEMTOBEAPPROPRIATEFOROURPLANT
PRODUCTIONNEEDS,THESPIRAL-TYPEANDTHECBP-
COMPATIBLETYPE,BUTBEFOREMAKINGOURDECISION,
WENEEDTOUNDERSTANDANYISSUESWITHRESPECT
TODOUGHPROCESSINGANDFINALBREADQUALITY.
CANYOUPLEASEADVISEUS?
Thefirstpointtomakeisthatbothmixertypesareperfectlysuitablefor
makingbreadusingaNTDprocess.Inmanyways,yourchoicewillbedic-
tatedbythetypeofbreadthatyouwishtomakeandthefinalcharacteristics
thatyourproductsshouldhave.Wehavelistedbelowthemaintechnical
issuesthatyoushouldconsiderinmakingyourchoice.
Plantcapacityandmixingtimes
Clearlyitisimportanttoensurethatyoucanprovidesufficientdoughto
sizecapabilityofthemixer.Youwillalsoneedtoconsiderthemixcycle
time;thatthis,thelengthoftimefromthestartofingredientdeliverytothe
mixeranddeliveryofthemixeddoughtothedivider.Themixcycletimewill
includetheactualdoughmixingtimealongwithalloftheloadingandtransfer
timesrequired.Ingeneral,forreasonsdiscussedbelow,theactualmixingtime
(notthemixcycletime)forspiral-typemixersislongerthanthatfor
Chorleywoodbreadprocess(CBP)compatiblemixers;typicalmixingtimes
wouldbe8

14minutesforthespiral(see
Section4.1.12
)and3

5minutes
fortheCBP.Thesetimesmayvarybutitisworthnotingthatoptimummixing
timesforCBPdoughsarequotedas2

5minutes(
CauvainandYoung,2006
).
Energyinputanddoughdevelopment
Duringthemixingcycleenergyistransferredtothedoughbythemechani-
calactionoftheimpeller.Thisenergyisanimportantpartofthedevelopment
ofaglutenstructureinthedoughwiththeappropriaterheologicalandgas
(see
Section9.3
)thoughthepreciseeffectsofincreasingthelevelofenergy
inputtothedoughwillvaryaccordingtoflourquality(
Cauvain,2015
).
Thetotallevelofenergytransferredtothedoughduringmixingdepends
toasignificantdegreeonthelengthofthemixingtime;thelongerthemix-
ingtime,thegreaterthetotalenergytransferred.However,ithasbeen
knownforsometime(
CauvainandYoung,2006;Cauvain,2015
)thatthe
rateatwhichenergyistransferredtothedoughalsohasanimpact;in
ProcessesandEquipment
Chapter|9
445
general,thefasterthemixingspeedthefastertherateofenergytransferand
entsanddoughrecipe.CBP-compatiblemixersexploitthiseffectbyrunning
atahigherspeedthanmanyspiral-typemixerswhichexplains,inpart,why
optimummixingtimesareshorterwithCBP-typemixers.
Therateofenergytransfertothedoughduringmixingalsodependson
used.Inthecaseofspiral-typemixers,theintroductionofastaticbarora
twinspiralarrangementmaybeusedtoincreasetherateofenergytransfer
tothedoughandshortenmixingtimes.Inthecaseofthelatterformofspiral
mixer,youcouldarguethatthisistheequivalentofaCBP-typemixerbut
thereareotherconsiderationstobetakenintoaccount(seesection:Dough
temperaturecontrol).
Doughtemperaturecontrol
duringmixinganditsfinaltemperature;thehigherthetotalenergyinput,the
higherthefinaldoughtemperatureforagivenrecipeandbatchsize.In
doughmixing,themostcommonwaytocontrolthefinaldoughtemperature
isthroughtheadjustmentoftheinitialwatertemperature(
Cauvainand
Young,2008
).Itiscommonpracticetohaveasufficientsupplyofchilled
wateravailableinthebakeryfordoughmixingtohelpwiththecontrolof
thefinaldoughtemperatureandinsomecasesiceorice-slushmaybeadded
atthestartofmixing(see
Section4.1.11
).
TypicalfinaltemperaturesforCBP-typedoughwillbeintheorderof
28

32

Cwhilethoseforspiralmixeddoughwouldbe24

28

C.
Traditionally,spiralmixeddoughtendstohavealowerfinaltemperature
becauseusuallylessenergyistransferredduringmixing.CBP-typedough
tendstohaveahigherfinaldoughtemperaturenotonlybecauseofthehigh-
erenergyinputbutbecausetheincreaseddoughdevelopmentyieldsadough
withrheologicalcharacteristicswhichallowittobereadilyprocessedonthe
doughmake-upplantatthehighertemperature.
Doughgasbubblestructureandproductcellstructure
Thecreationofthegasbubblestructureindoughdependsontheentrain-
mentandsub-divisionofairduringdoughmixing(
Cauvain,2015
).Manyfac-
torsinfluencethegasbubblepopulation(i.e.,thenumbersandsizesofgas
bubbles)inthemixeddough.Theinitialgasbubblestructureinthemixed
doughisamajorcontributingfactortothefinalproductcellstructure.Itissig-
nificantlyaffectedbythemixertype.ThisisanimportantissueaswithNTDs,
thereisnosignificantopportunityduringprocessingtosignificantlymodify
thegasbubblepopulationtoreduceitsaveragesize.Inpractice,whenthe
doughleavesthemixerthemainchangeforthegasbubblesistoincreasein
size.Thusifafineanduniformcellstructureisrequiredinthefinalproduct
446
BakingProblemsSolved
essentiallyitmustbecreatedinthemixer.Asgasbubblesgrowafterleaving
themixer,itiseasiertocreateacoarsercellstructureinthefinalproduct.
Themeasurementofgasbubblepopulationsinmixeddoughhasshown
thatspiralmixeddoughhasahigheraveragebubblesizeandawiderrangeof
sizesthantypicallyseenwithCBP-typemixers(
).Asthe
initialgasbubblepopulationisamajordeterminantoffinalproductcellstruc-
ture,thismeansthatspiralmixeddoughtendstoyieldfinalproductswitha
greateraveragecellsizewithawiderrangeofsizes;inpracticaltermsthecell
structureofbreadfromspiralmixeddoughwillhaveacoarserandlesseven
structurethanthosefromCBP-typemixers(butseethefollowingsection).
Themodificationofproductcellstructure
Theprecedingcommentsonthecreationofgasbubblepopulationsand
productcellstructuresareimportantinunderstandingoneofthekeyprinciples
oftheCBP,namelythecontrolofproductcellstructurethroughthemodifica-
tionofthemixerheadspacepressure(
CauvainandYoung,2006;Cauvain,
2015
).Spiral-typemixersdonotcommonlyhaveafacilityforcontrollingthe
mixerheadspacepressureasthemixerbowlismostlyopentotheatmosphere.
ThebowlofthetrueCBP-compatiblemixercanbeisolatedfromthesur-
roundingatmospherebymeansofloweringaclose-fittinglid.Historically
(
CauvainandYoung,2006
),theatmosphericpressureinthemixingbowl
wasreducedbelowthatofatmosphericpressuretocreateafinerandmore
uniformcellstructureinthebread(withaccompanyingadvantagesforcrumb
softness).Later,developmentsoftheCBP-compatiblemixer(
Cauvainand
Young,2006
:
Cauvain,2015
)includethefacilitytohavepressuresaboveor
belowatmosphericand,mostimportantly,tochangefromonepressureto
anotherduringthemixingcycle.Thisdevelopmentenablesthecreationof
differentgasbubblepopulationsinthedoughandthereforedifferentcell
structuresinthefinalproduct.Inpractice,thismeansthatthesamemixer
canbeusedtocreatethefineanduniformcellstructurerequiredforsand-
wichbreadorthecoarseopenstructurerequiredforFrenchbreadtypessim-
plythroughthemanipulationofmixerheadspacepressure.Thereareno
spiralmixersavailableatthetimeofwritingwiththiscapability.
References
Cauvain,S.P.,2015.TechnologyofBreadmaking,thirded.SpringerPublishingInternational
AG,Switzerland.
Cauvain,S.P.,Young,L.S.,2006.TheChorleywoodBreadProcess.WoodheadPublishingLtd,
Cambridge,UK.
Cauvain,S.P.,Young,L.S.,2008.BakeryFoodManufacture&Quality:WaterControland
Effects,seconded.Wiley-Blackwell,Oxford,UK.
Cauvain,S.P.,Whitworth,M.B.,Alava,J.M.,1999.Theevolutionofbubblestructureinbread
doughsanditseffectonbreadstructure.In:Campbell,G.M.,Webb,C.,Pandiella,S.S.,
Niranjan,K.(Eds.),BubblesinFood.AmericanAssociationofCerealChemists,St.Paul,
MN,pp.85

88.
ProcessesandEquipment
Chapter|9
447
9.3CANYOUEXPLAINTHEROLEENERGY
INTHECHORLEYWOODBREADPROCESS?
ThetransferofmechanicalenergytothedoughduringmixingwiththeCBP
isanessentialcomponentinthedevelopmentofadoughwithspecificrheo-
mumvolumeandcrumbcellstructure(
CauvainandYoung,2006
).When
firstintroduced,theoptimumworkinputlevelfortheCBPwasreportedas
11Wh/kgdoughinthemixerfortherangeoffloursthatwereavailablein
the1960s,butlater,workhasshownthattheoptimumtotalworkinputvar-
ieswiththetypeofflourbeingused,see
Fig.9.1
(
Cauvain,2015
).Thereare
anumberofreasonsforthischangewhichincludethedevelopmentofnew
workwascarriedoutwhenpotassiumbromatewasapermittedoxidant).
TheroleofenergyintheCBPhasstilltobefullyexplaineddespitethe
factthattheprocesshasbeenaroundfor50years.Itisverylikelythat
thehighenergyinputsarecapableofmechanicallybreakingthedisulphide
FIGURE9.1
Effectofworkinput:(A)5:(B)8;and(C)11Wh/kgdough.
448
BakingProblemsSolved
(
s
S
s
S
s
)bondsholdingtheoriginalproteinconfigurations.Inthisway,
mechanicalenergycanbelikenedtotheeffectsofnatural(enzymic)or
chemicalreduction.Thismayexplaininpartwhytheadditionofachemical
reducingagentlike
L
-cysteinehydrochlorideisconsideredtoreducethe
energyrequiredfordoughdevelopment.
Chamberlain(1998)

oneoftheco-inventorsoftheCBP

considered
thatonlyabout5%oftheavailableenergywasrequiredtobreakthedisul-
phidebonds.AsignificantpartoftheenergyinputduringCBPdoughmix-
ingwillbetakenupwiththemixingoftheingredientsandbreakingweaker
bonds.Inbreakingthedisulphidebondsenergymaywellplayaroleinopen-
ingpotentialsitesforoxidation.TheCBPmaythereforebeconsideredasa
redox-type
process,thatis,acombinationofmechanicalreductionandchem-
icaloxidationincontrasttoclassicalchemicalreductionandoxidation.
AsweconsidertheroleofenergyintheCBP,wemustrecognisethata
therateatwhichenergyisdelivered.Youcanincreasethetotalenergy
impartedtodoughsbylengtheningthemixingtimebuttheeffectonbread
qualityisnotasgoodasifthesametotalenergyisdeliveredatafasterrate.
IntheoriginalCBP,thedeliveryofenergywasneededwithin2to5minutes
ofmixingandthesamepremiseholdstruetoday,evenwhenflourswhich
energydeliverywithinthespecifiedtimes,itisnecessarytomixfasterwhich
inturn,requiresamoresubstantialmotorbeingfittedtothemixer.
Inadditiontonotingtherateeffect,weshouldalsorecognisethatthe
inputofenergytothedoughismanifestasasignificanttemperatureriseand
thattheprovisionofsuitablequantitiesofchilledwaterarerequired.Itmay
doughtemperaturescanbemaintainedatacceptablelevels,typicallyaround
30

C(
CauvainandYoung,2006
).
References
Cauvain,S.P.,2015.TechnologyofBreadmaking,thirded.SpringerPublishingInternational
AG,Switzerland.
Cauvain,S.P.,Young,L.S.,2006.TheChorleywoodBreadProcess.WoodheadPublishingLtd,
Cambridge,UK.
Chamberlain,N.,1998.Doughformationanddevelopment..In:Brown,J.(Ed.),TheMaster
pp.47

57.
ProcessesandEquipment
Chapter|9
449
9.4WEARELOOKINGTOBUYANEWFINALMOULDER
FOROURBREADBAKERY.CANYOUADVISEUSONTHEKEY
FEATURESWHICHSHOULDLOOKFORANDHOWTHEY
MIGHTIMPACTONFINALBREADQUALITY?
Themainfunctionofthefinalmoulderistochangetheshapeoftheindividual
doughpiecestofittheproductconceptanddeliverthemintheappropriate
formforfinalproof.Astherearemanydifferentsizesandshapesofbread
Atypicalbreaddoughmoulderwillcompriseachutefeedingthepieces
intoaseriesofrollers(2

4innumber).Typically,thepiecesenteringthe
yieldaflattenedellipticalshapeonexit.Immediatelyonleavingtherollers,
theleadingedgeofthedoughpancakeisliftedbyachainandthedough
pieceisrolleduplikeaSwissrollbeforebeingcarriedunderneathafinal
ofthemoulderisadjustedtoyieldthedesiredshape.Sideguidebarsmaybe
fittedunderthemouldingboardtohelpdeliveracylindricalshapeddough
piece(amostcommonshapeforbreadproducts).
Thebehaviourofthedoughpiecedependsinpartonthedoughmaking
processwhichhasbeenused.Doughwhichhasundergoneaperiodofbulk
becomede-gassed,andthisactioncancontributetomakingthecellstructure
ofthefinalproductfinerandmoreuniform,thoughnottothesamedegree
aswouldbeseenwithdoughspreparedbyaNTDprocess.
anintegralfeatureofthefinalproductandsode-gassingofthedoughisnot
advisable.Insteadthemouldingactionwillbedesignedtoaidtheretentionof
thelargegasbubblesthoughmechanicalmouldingisneverlikelytodeliver
thesamefinalproductcellstructurethatcanbeachievedwithhandmoulding.
ModernNTDshaverelativelylowlevelsofgasinthemandsothe
alsohaveadifferentrheologicalcharacterandrespondquitedifferentlyto
heavypressuresduringfinalmoulding.Inmanycasesthepressurescanlead
todamageofthegasbubblestructureinthedoughwhichinturnleadsto
qualityproblemsinthefinalproduct(see
Sections4.1.6
and
4.1.7
).Such
qualitylossesarelesslikelytooccurwithlongermouldingboards.
thinlyandusingjustenoughpressureunderthemouldingboardtoachieve
agreaternumbersofrolls.
Furtherreading
Cauvain,S.P.,2015.TechnologyofBreadmaking,thirded.SpringerPublishingInternational
AG,Switzerland.
450
BakingProblemsSolved
9.5WHYISABREADDOUGHPIECECOILEDAFTER
IMPACTONBREADQUALITY?
Therationaleforcoilingadoughpieceiscloselyconnectedwiththeprocess
aftermixingtodevelopthedoughreadyfordividingandprocessingas
unitshapes.
Thedensityofdoughattheendofitsbulkfermentationperiodisvery
lowandasmuchas70%ofthedoughvolumemaycomprisegasbubbles,a
mixtureofmostlynitrogenandcarbondioxide,ofvarioussizes(
Cauvain,
2012
).Someofthegasbubblesmaybeverylargeinsize(severalcm)andif
commonlyleadtotheformationofunwantedholesinthecrumbofmany
ta).Suchlargegasbubblescanreadilybeexpelledfromthedoughpieceby
flatteningthembyhandorbypinningthedough.Analternativewastopass
brakeandgraduallyeliminatethelargebubblesbyburstingthem.Asimilar
processtothelatterwasachievedbypassingthedoughthroughaseriesof
mostcommonformofbreaddoughmoulders.Theexpressionofthelarge
gasbubblesfromthedoughpieceisanimportantcontributortotheforma-
tionofafineanduniformcellstructureinthebakedproductwhichinturn,
isanimportantcontributortobreadcrumbsoftnessandbrightness;bothare
seenasdesirablecharacteristicsinwhiteandmanyotherbreadtypes.
Theformationofarounddoughpieceafterdividingisacommonprac-
tice,evenifhandmouldingisundertaken.Whensuchdoughpiecesare
coiled(rolledlikeaSwissroll)toformacrudecylindricalshapeforfinal
processing(
Cauvain,2015
).Thenumberofcoilsthatareachievedwhencre-
moulderandthespeedatwhichthedoughpiecepassesthroughit.The
weightandpositioningofthecurlingchaintocatchtheleadingedgeofthe
flatteneddoughalsohasanimportantparttoplayinformingthecoil.
willalwaysresultinanellipticalshapeonexitfromtherollers.Thisis
becausetherollersgriptheleadingedgeofthedoughpieceasitfallsunder
theinfluenceofgravityintotherollgap.Asthedoughpieceleavesthefinal
degreeofstretchingdependsontheequipmentdesign.Aconsequenceof
formingandellipticalshapeisthatdistributionofdoughinthecoilwhichis
ProcessesandEquipment
Chapter|9
451
formedisnotuniform.Ifthecoiledpiecewascutlongitudinally,thenit
wouldbeseentocompriseaseriesofwideandnarrowlayers(
Cauvain,
2015
)whichhasprofoundimplicationsfortheformationofthecellstruc-
tureinthefinalproduct.
thenumbersofcoilsthatareachieveddeliversafinerandmoreuniform
crumbcellstructureinthebakedproduct.However,itshouldbenotedthat
thevolumeofgasinNTDpiecesreachingthefinalmoulderisconsiderably
lower(typically
,
20%)thanthatfrombulkfermentationsystems(typically
oftheproductwillbelessmarked.
References
Cauvain,S.P.,2012.Breadmaking:anoverview.In:Cauvain,S.P.(Ed.),BreadMaking:
ImprovingQuality,seconded.WoodheadPublishingLtd.,Cambridge,UK,pp.9

31.
Cauvain,S.P.,2015.TechnologyofBreadmaking,thirded.SpringerPublishingInternational
AG,Switzerland.
452
BakingProblemsSolved
9.6WHATISTHEFUNCTIONOFFOUR-PIECING
ORCROSS-PANNINGINBREADMAKING?
Four-piecing(see
Fig.9.2
)isatechniquecommonlyusedintheproduction
ofsandwichstylebreadswhereafine(smallaveragecellsize)anduniform
cellstructureisrequired.Inessence,itconsistsofmouldingadoughpiece
toalongcylindricalshapeunderthefinalmouldingboardandthencutting
thepieceasitexitstheboardintofourpiecesofequalsizeorweight.The
fourpiecesareturnedthrough90

placedinthepan.
elongatedinthedirectionofthedoughmovementthroughthefinal
moulder.Aftercurlingthecellsmainta
intheirelongatedshapebecausethe
visco-elasticpropertiesofdoughan
dthecurlingprocessitselfprevent
thebubblesfromassumingasphericalshape.Insinglepiecebread,the
cellsformedfromthesebubblesare
cutthroughtheirshortsidesin
theproductandthecellwallscastas
ignificantshadow,thusgivingthe
crumbadull,greycolour.
Infour-piecingturningthepiecesthrough90

meansthattheelongated
cellsarecutthroughtheirlongaxisandtheresultantshallowcellswhich
formintheloafwillcastlessofashadowwhenviewedunderglancinglight.
Thismeansthatthecrumbfromfour-piecedbreadwillbeseenasbrighter
whenviewedundersimilarlightingconditionstothatofasinglepieceloaf.
Inadditiontotheimprovementincrumbappearancethereisanimprovement
incrumbsoftnessandasmallbuthelpfulimprovementincrumbresilience
whenusingfour-piecing.Thelatterhelpswiththeslicingandeatingproper-
tiesofsuchbreads.
Althoughthereisanimprovementi
ncelluniformitywithintheindi-
vidualpieces,therecanbegreaterslicetoslicevariationalongthelength
FIGURE9.2
Four-piecingofbreaddoughs.
ProcessesandEquipment
Chapter|9
453
oftheloafwithfour-piecing.
CauvainandYoung(2006)
reviewedthis
effectandprovidedcellsizedatatoconfirmthataperiodicstructure
wascreatedalongthelengthoftheloafbyfour-piecing.Thisisespe-
ciallytruefortheareaswheretwopiecesmeetandsoitisimportantto
ensurethatthefourpiecesareasequalaspossibleanduniformlyplaced
inthepan.
Eight-piecedloavesareknown,thoughnotcommon,andasimilartech-
niqueiscrosspanningorcrossgraining.Bothtechniquesrelyonthe
reorientationofthecellstructureinthedoughtodeliversimilarbenefitsto
thosedescribedabove.
Reference
Cauvain,S.P.,Young,L.S.,2006.BakedProducts:Science,TechnologyandPractice.Blackwell
PublishingLtd,Oxford,UK.
454
BakingProblemsSolved
9.7WHATISPURPOSEOFTHEKNOCKING-BACKTHE
DOUGHWHENUSINGABULKFERMENTATIONPROCESSTO
MAKEBREAD?
Inbulkfermentationbreadmakingprocesses,thedoughislefttofermentin
asuitableenvironmentforalongperiodoftime,oftenmanyhours.During
thisfermentationperiod,thevolumeofthedoughwillincreasegreatlyasthe
approximately70%ofthedoughvolumeattheendof2or3hoursoffer-
mentationmaybegas.
Knocking-backthedoughisanoperationcommonlyperformedpart-way
throughtheprescribedfermentationperiod,typicallyafterhalfandusually
beforethreequartersoftheprescribedperiod.However,somemoretradi-
tionalrecommendations(
BennionandStewart,1930
)arethatknocking
backshouldbecarriedoutintheearlystagesofbulkfermentation.In
small-scaleproduction,theoperationmaywellbecarriedoutbyandhand,
andthispracticehasgivenrisetoanalternativedescriptionoftheprocess

punchingthedough.Withlargerbulkdoughs,thereisnoreasonwhythe
processcannotbecarriedoutwithamixingmachinethoughthemixing
timewillusuallybeveryshort,commonlyonlyamatterofacoupleofmin-
utesonslowspeed.
Anumberofdifferentreasonsaregivenforcarryingoutaknock-back
anditverylikelythattheyallhavesomevalidity.Theyincludethe
following:

Toeven-outtemperaturevariationsinthebulkofthedough.

Thereis
nodoubtthatwhenabulkdoughstandsforlongperiodsoftimethatthe
surfaceofthedoughwillcool,inpartastheresultofsurfaceevaporation
andthesidesincontactwiththedoughbowlmayalsobeatadifferent
temperaturedependingonthebakeryenvironment.

Toreducetheriskofthedoughskinningfromsurfaceevaporation

Excessiveskinningofthedoughcanleadtosignificantproductquality
problemswhenthedriermaterialisdistributedthroughoutthedoughat
thetimeofdividing.

Toreinvigoratetheyeastbyeliminatingwasteproducts

Inthiscase,
thewasteproductisalcohol,highlevelsofwhichcanhaveaninhibitory
effectonyeastactivity.
Onepotentialbenefitofknockingbackthedoughnotcommonlydis-
cussedisthecontributionthattheenergyofthisre-mixingmaymaketo
knock-backis)transferssomeenergytothedough(evenbyhand)and
ProcessesandEquipment
Chapter|9
455
ingtonotethat
BennionandStewart(1930)
recommendthatabundough
shouldbeknockedbackevery20minutesifabunofgoodbulk(volume)
andsilk-liketextureisrequired.
Reference
Bennion,E.B.,Stewart,J.,1930.CakeManufactureandSmallGoodsProduction.LeonardHill
Limited,London,UK.
456
BakingProblemsSolved
9.8WEHAVETWOBREADLINESRUNNINGSIDE-BY-SIDE
WITHTHESAMEEQUIPMENTBOUGHTATDIFFERENTTIMES.
VOLUMEANDCELLSTRUCTUREWHENMAKINGTHESAME
PANBREADPRODUCT.WECOMPENSATEBYADJUSTING
CRUMBCELLSTRUCTURE.CANYOUHELPUSUNDERSTAND
WHATISHAPPENING?
TheoperationoftheCBPisalmostuniqueinthatthecrumbstructurecan
bemanipulatedbyadjustingthemixerheadspacepressuretocreatediffer-
entstructures.Inyourcase,youares
eekingafineanduniformcellstruc-
tureinyoursandwichbreadproducts,a
nditiswiththeseproductsin
particularthatyouarenoticingadi
fference.Withthemixersonboth
plants,youareapplyingapartialvacuum,theapplicationofwhichis
delayeduntilpart-waythroughthemix
ingtoencouragetheinitialoxida-
tionofthedoughbyascorbicacidbe
foremovingtodelivertherequired
doughtothedivider.
Thesametypesofmixerswerepurchasedatseparatetimes.Initially,you
didnotuseoneofthemwithpartialvacuumeventhoughthemixerhadthe
capability.Closeinspectionoftheequipmentrevealedthatthetwopressure
gaugeswhichwerefittedtothemixerwereofdifferenttypessothatwhen
ferentpressuresinthemixingchamber.Onedialreadsdownfrom0to30
v
ofvacuumandtheotherreadsupfrom0to30
v
ofpressure.Youhavebeen
v
.
Theseareoldreadingsanditwillbeeasierifweconvertthemtomore
modernunits

bars;inessenceatmosphericpressureis1bar.Inthecase
whereaswiththedialreadingpressure,itisaround0.67bar.At0.33bar,
wewouldexpectyoutoloseoxidationandhavepotentialproblemswith
coarsenessofcrumbcellstructure(see
Section4.1.9
).Ifyouadjustthe
vacuumdialto10
v
(0.33bar),youshouldmorecloselymatchbread
quality.
Itwasalsointerestingtorecordtha
tyouwereusingdifferentwater
apparentlywasinresponsetothe
apparentlydifferentconsistenciesofthedoughleavingthetwomixers.
Thiswasnotsurprisingsincethelevelofgaswhichremainedinthetwo
doughsex-mixerwouldbedifferentandthiswouldgiverisetotheper-
ceiveddifferencesindoughconsistency.Oncethevacuumlevelshadbeen
ewaterlevelsinthedoughbecame
comparable.
ProcessesandEquipment
Chapter|9
457
Authorsnote:
Therecanbeconfusionoverpressureunitswhentalking
aboutpartialvacuumbecauseofthecommonuseofatmosphericpressureas
astandard.Onebarisdefinedas10
5
N/m
2
(nearlyequalto1atm,i.e.,
760mmor30
v
mercury).Atmosphericpressuresdovarywithenvironmental
conditionsandheightabovesealevel.Theaboveproblemwasforabakery
atsealevel.
Furtherreading
Cauvain,S.P.,Young,L.S.,2006.TheChorleywoodBreadProcess.WoodheadPublishingLtd,
Cambridge,UK.
458
BakingProblemsSolved
9.9WEHAVEBOTHSPIRALANDTWIN-ARMTYPEMIXERS
ANDWOULDLIKETOPRODUCEAFINERCELLSTRUCTURE
WITHOURSANDWICHBREADS;CANYOUSUGGESTWAYS
INWHICHWEMIGHTACHIEVETHISAIM?
Muchofthefinalstructureofbreadisdeliveredbythemixer,primarilythe
designofthemixingtoolsandthemixingaction.Duringthedoughmixing
process,smallairbubblesaretrappedinthedevelopingglutennetwork.
mixingactionswithsomeinputfromingredientslikefatandemulsifiers
bowlsofspiralandtwin-armtypemi
xersareusuallyopentotheatmo-
sphere,sothereisnoopportunitytoad
justtheinitialgasbubblepopulation
inthedoughbychangingpressuresasisthecaseintheCBP(
Cauvainand
Young,2006
).
Duringandimmediatelyafterdoughmixing,thereisagradualchangein
thecompositionofthegasesinthebubblestrappedinthedough.Initially,
thebubblestrappedinthedoughcontainamixtureofnitrogenandoxygen
butthelatterisscavengedbytheaddedyeast,aswellastakingpartinthe
doughoxidationprocess.Eventually,onlynitrogengasremainsinthe
entrainedairbubbles.Astheyeastbeginstoproducecarbondioxide,itgoes
firstintosolutioninthedoughliquorandthenlateritdiffusesintothenitro-
gengasbubblesandexpansionofthedoughbegins.
Theexpansionprocessesinthedougharecomplexandarerelatedtothe
initialgasbubblessizebutinsummarywhathappensisthatthelargergas
bubblestendtoexpandtoaproportionallygreaterextentthanthesmall
ones.Essentially,thelargergasbubbleshavealowerinternalpressureand
thenaturaldrivingforceisforcarbondioxidetodiffuseintothem.
slowlyandinsomecasemayceasetoexistinthedough.Asthegasbubbles
continuetoexpandinproofandtheearlystagesofbakingtheygrowlarge
thebasisofthecellstructureintheloaf.
Themixersthatyouareusingtendtodeliveraninitiallywiderangeof
gasbubblesizeswhichultimatelybecomesawiderangeofcellsizesinthe
loaf,sothatthecellstructuretendstobeconsideredcoarsebycomparison
withtheveryfinecellsstructuresthatmaybeachievedwithothertypesof
mixers(e.g.,CBP-compatible

See
Cauvain,2015
).Thereislittlethatyou
candointhemixertochangethesituationsoanyimprovementswillhave
tobeintroducedduringdoughprocessing.
Onewayofproducingafinercellstructureistode-gasthedough.In
ingthesmallerones.Thede-gassingprocessesdeliversamoreuniformgas
ProcessesandEquipment
Chapter|9
459
bubblepopulationwhichwillexpandmoreuniformlyduringproofand
deliveramoreuniform(andusuallyfiner)cellstructure.
Theeasiestwaytode-gasthedoughistoallowittohaveashortperiod
offermentationinbulk(e.g.,1hour)andtode-gasportionsofthedoughby
passingthembackandforthafewtimesthroughapastrybrake,thiswill
doughtorecoverandthendivideintounitsandprocessthedoughasbefore.
doughtorecoveritsextensibilityandavoidstructuraldamageinthesubse-
quentmoulding.
References
Cauvain,S.P.,2015.TechnologyofBreadmaking,thirded.SpringerPublishingInternational
AG,Switzerland.
Cauvain,S.P.,Young,L.S.,2006.TheChorleywoodBreadProcess.WoodheadPublishingLtd.,
Cambridge,UK.
460
BakingProblemsSolved
9.10WEHAVEBEENFREEZINGSOMEOFOURBAKERY
PRODUCTSTOHAVEPRODUCTSAVAILABLEINTIMESOF
PEAKDEMAND.WENOTICETHATTHEREISSNOWORICE
INTHEBAGSWHENWEREMOVETHEMFROMTHEFREEZER.
CANYOUTELLUSWHYTHISHAPPENSANDHOWIT
CANBEAVOIDED?
practice.Breadandrollsifwrappedtopreventanymoisturelosseswillkeep
wellinthefrozenstate.Breadproductshaveahighmoisturecontentanda
highwateractivity.Oncefrozen,suchproductsshouldbestoredbelowtheir
glasstransition(Tg)temperature(see
Section11.6
).Effectively,thisisthe
temperatureatwhichallthesolublematerialsintheproductbecomeimmo-
bileorfrozen.Ithasbeenestimatedthatapproximately30%ofthewaterin
breadremainsunfrozenevenattheusualstoragetemperatureof
2
20

C.In
part,thisisbecauseoffreeze

concentrationeffectswhichmeansthatinprac-
ticenotallofthewaterintheproductisactuallyimmobile.
However,attypicalfreezertemperaturesanyevaporationofwaterfrom
theproductwillproceedveryslowly.Ifthetemperatureofthefrozenprod-
uctrisesaboveitsTgsomeofthemoisturepresentcanevaporateandsub-
limethroughtheproducttothesurroundingatmosphere;inthiscase,the
insideofthebaginwhichitispacked.Oncethere,thewatervapourfreezes
intoicecrystalsandbecomesvisibleassnowontheproduct(see
Fig.9.3
).
Withthereduction,forhealthreasons,ofsaltlevelsinbreadproducts,this
problemislikelytooccurearlierintheproductsfrozenlifethanpreviously.
Thisisbecausesaltisamaterialwhichhastheabilitytoholdontothe
moistureintheproductthuspreventingitsescapeasvapour.
Iftheproblemoccursfrequently,itwouldbewisetocheckthatyour
freezerisoperatingcorrectly(temperatureatorbelow
2
20

C)andtryto
minimiseanyopeningandclosingofitsdoorandcheckitsdefrosting
cycle.Itisalsobeneficialtoremoveproductfromfrozenstorageinstrict
FIGURE9.3
Icecrystalsformedinbreadpack.
ProcessesandEquipment
Chapter|9
461
rotationsothatanyoneproductdoesnotspendlongerthannecessaryin
frozenstorage.Inaddition,careshoul
dbetakenthatanyproductwhichis
removedfromthefreezerisnotleftinawarmatmosphereasthelocalized
meltingoftheiceparticlesprovid
eagoodenvironmentforeventual
mouldgrowth.
Theproblemcanbegreaterwithcakeproductsbecausethepresenceof
sugarsintherecipelowersthefreeingpointoftheproductevenfurtherthan
thatofbreads.Insomecases,thesugarconcentrationcanbesohighthatthe
cakeisnotfrozenevenat
BakingProblemsSolved
9.11WEHAVEBEENDEEPFREEZINGBREADPRODUCTS
ANDEXPERIENCEANUMBEROFPROBLEMSWITH
DIFFERENTPRODUCTS.WITHCRUSTYPRODUCTS,
WEOBSERVETHATTHECRUSTFALLSOFFWHILEWITH
SOMEOTHERPRODUCTSWEFINDTHATLONGERPERIODS
OFSTORAGELEADTOTHEFORMATIONOFWHITE,
TRANSLUCENTPATCHESINTHECRUMBWHICHAREVERY
HARDEATING.ARETHEPROBLEMSRELATEDTOTHE
PERFORMANCEOFOURFREEZER?
Thefirstofyourproblemsiscommonlyreferredtoasshelling,thatisthe
lossofthecrustfromfrozenbakeryitemswhichmayoccurduringstorage
butmorecommonlyitmanifestsitselfwhentheproductisdefrosted.Similar
problemsmaybeobservedwithsomepart-baked,frozenproducts.
Whenallbreadproductsleavetheoven,themoisturecontentofthecrust
regionismuchlowerthanthatofthecrumb.Thisdifferentialinmoisture
contentismuchgreaterincrustyproductsthanwithmanyothertypesof
bread,e.g.,sandwichbreads,andisanintegralpartofthecharacterofthe
partlyresponsiblefortheirdifferencesintexture,withthelowmoisturecrust
havingaharder,morerigidcharacterthanthehighermoisturecontent,soft
crumb.Thedifferenceinmoisturecontentalsomeansthatthesaltconcentra-
tionishigherinthecrustregionthanthecentrecrumbwhichwilllowerthe
temperatureatwhichiceformsintheseregions.
Thecombinationofdifferentfreezingpointsandstructuralarchitecture
meansthatthecrustandcrumbwillexpandandcontractatdifferentrates
becomesogreatthattheybecomeseparatedfromoneanother.Thisphenom-
enonwilloccurunderalmostanyfreezingconditionsoitisunlikelythat
yourfreezerperformanceisdirectlytoblamefortheproblem.Youwillhave
toacceptthatyouareunlikelytosuccessfullyfreezecrustyproductsbecause
theonlysolutionistoallowequilibrationofmoisturebeforefreezing,but
thentheproductwouldnotbecrustyanyway!
Yoursecondproblemcouldwellberelatedtoyourfreezerperformance
andisaphenomenonknownasfreezerburn(
CauvainandYoung,2008
).
Itcomesfromthelossofwaterfromdifferentregionsofyourproductdur-
ingfrozenstorage.Ithasbeenestimatedthatabout30%ofthewaterin
breadremainsunfrozeninbread,evenat
2
20

C.Thisfreewatermay
leavetheproductandenterthefreezerorpackatmospherewhereiteventu-
allyshowsasfrost(see
Section9.10
).Thehard,translucentpatchesthat
youseeareareasofcrumbwhichhavebecomedehydratedinthefreezer.
Theconditionisexacerbatedbyanyperiodswhenthefreezerhasbeen
allowedtowarmtotemperaturesabovethefreezingpointoftheproduct.
ProcessesandEquipment
Chapter|9
463
Thehighertemperaturesacceleratemoisturelossesandtheslowre-freezing
whichfollowsalsocontributestothisparticularproblem.Wesuggestthat
youlookatyourfreezerperformanceandinparticularanychangesincon-
ditionsduringthedefrostcycle.Alsolookcloselyatyouroperatingproce-
duresandtrytominimisetheopeningandclosingofthefreezerdoor.This
isacommoncauseoftheproblembecausethecoldairislostandreplaced
bywarmerairwhichraisesthetemperatureoftheproductsnearesttothe
doororlid.
Reference
Cauvain,S.P.,Young,L.S.,2008.BakeryFoodManufactureandQuality:WaterControland
Effects,seconded.Wiley-Blackwell,Oxford,UK.
464
BakingProblemsSolved
9.12WEHAVESEENREFERENCESTOTHEMILTONKEYNES
PROCESSBUTCANFINDVERYLITTLETECHNICAL
INFORMATIONONTHEPROCESS.CANYOUTELLMEWHAT
ITIS(WAS)ANDHOWITIS(WAS)USED?
Thereisrelativelylittletechnicalliteraturewhichhasbeenpublishedon
theMiltonKeynesprocess(MKP).Launchedin1995,itwasapatented
process(
Anon,1995
)basedontheproductionofpart-bakedbreadsofmany
differentsizes,includingpanbreads,butdifferedfromotherpart-baked
productsofthetimeinthatanextendedambientshelf-lifeof5

12days
beforesecondbakingwasclaimed.Theprocesstookitsnamefromthe
cityintheUnitedKingdominwhichthepart-bakedbreadproductswere
manufactured(
Grindley,1996
).
baker,aplantbaker,amachinerymanufacturerandabreadimprovercom-
pany(
Bent,2007
).PanbreadsweremixedusingCBP-compatiblemixers,
whereasovenbottomandFrenchstickswerepreparedwithaspiral-type
mixer.Thedoughrecipeswereessentiallythesameaswouldbeusedwith
crumbsoftnessinthebreadafterbake-off.Therewerenospecialaspectsof
doughprocessing.Steamwasusedintheinitialbakeandcrustcolouration
waskepttoaminimuminthefirstbake.
Immediatelyafterleavingtheoven,
thewarmproductsintheirpansor
ontraysweretransferredtobecooled
undervacuuminadedicatedcooler.
Usingthistechnique,coolingtimes
werereducedforallproductsizes.
Aftercoolinganddepanning,thepr
oductsweresprayedwithapreserva-
tivesolutiontohelpachievethe5

12daysmould-freeshelf-lifeclaimed.
Itwasclaimedthatthepreservativ
ewasvolatilisedduringthesecondbak-
ingstage.Somein-storebakerie
swhichemployedtheprocesswere
equippedwithaminitravellingovenf
orbake-offthou
ghrackanddeck
ovenscouldbeused.
Ithasbeenwellunderstoodforquitesometimethatbreadstalingis
reversedbyasecondbake(
Cauvain,2015
)andthathasalwaysbeenan
underlyingprincipleforallbake-offbreadproducts.However,tofully
refreshtheproducts,thecoretemperaturemustexceed60

65

Candtherate
ofstalingafterthesecondbakeisconsiderablyfasterthanaftertheinitial
bake.Inpractice,thismeantthatconsumerswhowereusedtopurchasing
bakedproductswhichtook3

4daystobecomeunacceptablyfirmwere
facedwiththeMKPproductwhichcouldtakeaslittleas3

4hourstoreach
thesamestateunlessthebake-offprocesshadbeencarefullycontrolledand
fullre-freshinghadbeenachieved,thiswasoftennotthecaseinpractice
whentheMKPwasrolled-outintomanystores.Asaconsequencethelevel
aninitialfanfareofexcitementtheprocessslippedquietlyintohistory.
ProcessesandEquipment
Chapter|9
465
References
Anon(1995).Manufactureofbakedfarinaceousfoodstuffs,PatentWO95/30333.
Bent,A.J.,2007.Specialityfermentedgoods.In:Cauvain,S.P.,Young,L.S.(Eds.),Technology
ofBreadmaking,seconded.SpringerScience
1
BusinessMedia,NewYork,NY,
pp.245

274.
Cauvain,S.P.,2015.TechnologyofBreadmaking,thirded.SpringerPublishingInternational
AG,Switzerland.
Grindley,E.,1996.MadeinMiltonKeynes.BakersReviewJanuary,16

17.
466
BakingProblemsSolved
9.13CANYOUEXPLAINTHEPRINCIPLES
OFVACUUMCOOLINGOFBAKEDPRODUCTS
ANDITSPOTENTIALAPPLICATIONS?
Thevacuumcoolercomprisesasealablechamberinwhichtheinternalpres-
surecanbereducedtoalevelconsiderablylowerthanatmosphericpressure.
Whenthepressureinsideaclosedvesselisloweredandmaintainedbelow
atmosphericpressure,thetemperatureatwhichwaterboilsisconsiderably
lowered.Thisisbecausealiquidboilswhenitssaturatedvapourpressureis
equaltotheatmosphericpressure.Forexample,inthenaturalworldwater
boilsatprogressivelylowertemperaturesastheheightabovesea-level
increases.Theimpactofreducedpressureontheboilingpointofwatercan
beconsiderable;forexample,ifthepressureisreducedtohalfanatmosphere
(i.e.,0.5bar)theboilingpointfallsfrom100toaround80

C.
Asevaporationlossesplayamajorroleincoolingbakedproducts,hold-
ingtheproductsatlowerpressurestoextractthelatentheatconsiderably
reducesthecoolingtimerequired.Forexample,
Cauvain(2015)
compared
thecoretemperatureofloavescooledconventionallywiththosesubjectedto
vacuumcoolingandshowedthatthatthetimestakentoachieveatempera-
tureof25

Cwereabout100and10minutes,respectively.
Itshouldbenotedthatthevacuumcoolingconditionswillvaryaccording
tothetypeofproductbeingcooled.Thereareanumberofdifferentpointsto
consider.Thefirstisthateventhoughthetemperatureatwhichthewaterboils
hasbeenconsiderablylowered,therateatwhichmoistureleavesthecentreof
theproductwillbeaffectedbytheproductdimensions.Heat(andmoisture)
canonlybelostfromthesurfaceofthebakedproduct,anditwillalwaystake
longerfortheevaporationfronttoreachthecentreoftheproduct.Inpractice,
surfaceanditscentre.Forcrustybreadproducts,thismaybeacceptablebut
thiswillnotbethecaseforpanbreads.Thiseffectmaywellhavebeenoneof
thecontributingfactorstothedemiseoftheMKP(see
Section9.12
).
Somebakeryproductscanbenefittheapplicationofvacuumcooling.
Thisisespeciallytrueforproductswithdelicatestructureswhicharediffi-
culttohandleattheendofthebakingprocessesbutarekeytofinalproduct
Oneoftheclaimedbenefitsfortheapplicationofvacuumcoolingisthat
thenormalbakingtimecanbereducedbecauseofthecontributionthatvac-
uumcoolingmakestothephysicalstabilityofthebakedproductstructure.
Thisadvantagemaybenegatedbythelikelihoodthatoverallmoisturelosses
fromvacuumcooledproductsmaybehigherthanwithconventionalcooling.
Reference
Cauvain,S.P.,2015.TechnologyofBreadmaking,thirded.SpringerPublishingInternational
AG,Switzerland.
ProcessesandEquipment
Chapter|9
467
Thispageintentionallyleftblank
Chapter10
10.1WHATISMEANTBYHYDROGENIONCONCENTRATION
Thetermmeansjustwhatitsays,namelytheconcentrationofhydrogenions
degreeorintensityofacidityoralkalinityandisbasedonthefactthat,in
solution,themoleculesofsomesubstancessplitupanddispersethroughout
theliquidtoagreaterorlesserdegree.ThepHofaliquidtellsnotonly
whethertheliquidisacidoralkalinebutalsotowhatdegreeorextent.
ThesymbolpHstandsforthepotentialofhydrogen.Thewordion
meanstraveller,sothatthehydrogenionconcentrationreferstothedegree
ofdispersalofionsofhydrogeninagivensolution.Italsoreferstothefact
thatsuchhydrogenatomsareinanactiveconditionandarechargedwith
positiveelectricity,commonlydenotedasH
1
.
Tounderstandthismore,wemustconsiderthestateofaffairsinpure
water.Thisisneitheracidnoralkaline,butithasbeencalculatedthatinneu-
tralwateronemoleculein10millionionisesorsplitsupanddispersesas
oneatomofhydrogenchargedwithpositiveelectricityandonegroupofele-
mentsconsistingofanatomofhydrogenandoneofoxygen.Thisisknown
asahydroxylgroupandischargedwithnegativeelectricity(OH
2
).Thereis
thereforecompleteneutrality,thepositivechargeonthehydrogenatom
exactlyneutralisingthenegativechargeofthehydroxylgroup.
Inpurewater,beingneutral,onlyonepartin10millionpartsisinthis
stateofionisation.Mathematically1/10,000,000canbeexpressedas10
2
7
,
thatis,10totheminusseventhpower.Hence,instatingthepHofaneutral
liquidlikepurewaterscientistswritepH7,omittingtheminussignasbeing
superfluous.
isahigherconcentrationofhydrogenionssuchasisthecasewhenanacid
isdilutedwithwater.Here,theremaybeonepartionisedhydrogenina
millionpartsoftheliquid.Thiscanbeexpressedas1/1,000,000,thatis,
10
2
6
andsoiswrittenpH6.Thisshowsthattheliquidisacidincharacter,
butnotverystronglyso,foronlyonepartinamillionisactivelyacidor
capableofreactingasanacid.
469
BakingProblemsSolved.DOI:
http://dx.doi.org/10.1016/B978-0-08-100765-5.00010-2

2017ElsevierLtd.Allrightsreserved.
Thegreatertheintensityoftheacidthegreatertheconcentrationof
hydrogenionswillbe.TheexpressionspH5,pH4,pH3,pH2andpH1
mean,respectively,thatonepartin100,000,10,000,1000,100,and10are
inthiscondition.AsthenumeralbesidethepHdecreases,theintensityof
theacidpresentintheliquidincreases(see
Fig.10.1
).
Inthecaseofneutralsolutions,westillrefertothehydrogenioncon-
centration,butthedispersedatomscha
rgedwithpositiveelectricitymay
notnecessarilybehydrogen.Thegroupsofnegativelychargedelements,
however,neutralisetheseandalkalinereactionsarerecorded.For
example,insodiumhydroxide,awell-knownalkali,theionisedmolecule
willsplitupintooneatomofsodiumandonehydroxylgroup.Theformer
carriesaweakpositivechargeandthehydroxylgroupastrongernegative
one,cancellingouttheweakacidtende
ncyandsubstitutingstrongeralka-
linetendencies.Thusstrongernegativ
eelectricalchargescanberecorded.
AsthepHnumeralincreasessoalkalinityincreases,andwheneverthe
numeralisaboveseventhesubstanceor
solutionofsubstancesisalkaline.
Thehigherthefigureaboveseventhegreaterthestrengthorintensityof
alkalinitywillbe.
Examplesofthevalueofthisinformationtothepracticalbakerand
confectionerinclude:

Thedevelopmentofropeinbread(see
Section4.1.4
).Ropesporescannot
growunlessthedoughorloafislackinginacidity.Thisdegreeofacidity
5.5,ropecannotgrowindoughorbread.
ConcentrationofH
+
ionpH
1gperlitre0
1gper10litres1
1gper100litres2
3
4
Acidincreasinginmultiplesof105
6
1gper10millionlitres7
8
9
Alkaliincreasinginmultiplesof1010
11
12
13
17
g
OH
p
erlitre14
FIGURE10.1
pHscale.
470
BakingProblemsSolved

Inthemanufactureofhigh-ratiocherrycake,thelowviscositycharacter
ofthebatterdoesnotpreventthecherriesfromsinkingduringbaking.
However,ifanadditionoftartaricacidismadetothebattertobringthe
aciditytopH5.4orless,thentheglutenoftheflourisstrengthenedand
batterviscosityincreasesintheearlystagesofbakingsothatthecherries
remainsuspendedduringbaking(see
Section5.7
).Highprotein,high-
ratiocakeflourrespondsevenmorereadilytotheuseoftartaricacid.
Chapter|10
471
10.2INSOMETECHNICALLITERATURE,THEREIS
REFERENCETOBATTERSPECIFICGRAVITYORRELATIVE
DENSITY.WHATISTHIS?HOWISITMEASURED?
ANDWHATISITSRELEVANCETOCAKEANDSPONGE
MAKING?WHYISTHEVOLUMEOFTHEBAKEDPRODUCT
REFERREDTOINTERMSOFSPECIFICVOLUME?
Itwouldseemlogicaltousethesameunitofmeasurementforexpressing
themassconcentrationofunbakedbattersandbakedcakeproducts.
However,whenconsideringhowthispropertyismeasured,itbecomes
clearerwhyalargepartoftheindustrycontinuestousethedifferent
measures.
Thedensityofasubstanceisitsmass(weight)dividedbyitsvolume.
Theamountofairoccludedinabatterismonitoredbymeasuringitscup
weight,thatis,theweightofbatterrequiredtofillacupofknownvolume.
Asthesamecupsizeorvolumeisusedforthecomparison,thecupweight
relatesdirectlytospecificgravity(nowmorecommonlyknownasrelative
density)andthisfigureisusedinthebakeryforprocesscontrolpurposes
withouthavingtomakeanycalculations.Thelighterthecupanditscontents
(i.e.,thelargerthevolumeofairinthebatter),thelowertherelativedensity.
Thus,batterrelativedensityandbatterspecificgravityessentiallymea-
surethesameproperty,thedegreeofaerationofthebatter.Batterrelative
densityincakemakingismostcommonlyrelatedtoproductvolume;usually,
thelowerthebatterrelativelydensity,thelargerthecakevolumeinagiven
10.3WHATVALUEISTHEREINMEASURINGCOLOUR
OFBAKERYPRODUCTSANDHOWCANWECARRYOUT
THEMEASUREMENTS?
Thecrustandcrumbcoloursofbakeryproductsareimportantpropertiesand
provideimportantforthebakerywithrespecttoingredientsandprocessing.
Crustcolourisoneoftheimmediatefeaturesofabakeryproductthatis
seenandrecognisedbyconsumers.Inmostcases,consumerswillseedevia-
tionsfromthenormalproductcrustcolourasanindicationthattheproduct
concerneddoesnothavethequalitythattheyareseekingandsomayreject
theproductasunsuitable.
Theformationofaparticularcrustcolourisdirectlyrelatedtoovenbaking
conditionsandtheproductformulation.Bothareimportantduetotheirrespec-
tiveinfluenceontheMaillardreactions(see
Section4.1.14
)whicharelargely
responsibleforthebrowncolourofthecrustofmostbakeryproducts.The
Maillardreactionproductsalsocontributetoproductflavour.Themeasure-
mentofcrustcolourisnotonlyausefulindicatorofvariationsfromtheprod-
uctnormbutcanalsobeusedtoaiddiagnosisofthosequalityproblems
whichcanchangethecolour.
Manyoftheingredientsusedinthemanufactureofbakeryproducts
makeadirectcontributiontocrumbcolour.Forexample,theintrinsiccolour
oftheflourendospermwillaffectbreadcolouraswillthelevelofashor
branpresentinawhiteflour(see
Section2.2.1
).Inthecaseofcrumbcolour,
thereisacomplicationarisingfromthecellularstructureitselfasdifferent
cellsizesreflectlighttodifferentdegrees,andthisaffectsthehumanpercep-
tionofcrumbcolour,especiallywhenthecrumbisviewedinglancinglight.
Thisisanimportantconsiderationasthisiscomparablewiththeassessment
ofproductcolourmadebyexpertsandconsumersalike.However,itissepa-
ratefromthefundamentalcolouroftheproduct.
Thereareanumberofdifferentwaysinwhichcolourcanbeassessedin
thebakery.Ithasbecomerelativelycommontomeasurethecrustandcrumb
colourofbakeryproductsusingvariousformsofcolorimeter.Thenumerical
outputofacolorimeterisrelatedtostandardsdevelopedbytheCommission
InternationaledelEclairageandcomprisesaseriesof
tristimulus
(i.e.,three)
valuesdefinedasXYZwhicharealsorelatedtootherdefinedcolourspaces,
suchasYxyandL

a

b

expressingthecolourofanobjectusingnumbersundercarefullydefinedand
controlledconditions.
Anumberofdifferentcolourspaceshavebeendevelopedovertheyears
hencethedifferentnotationsthatareencountered.However,thecommon
elementtoeachcolourspaceisthatthecolourofanobjectisdefinedby
threevalues.Thedifferentcolourvaluesarerelatedmathematically,soitis
commonforagivencolorimetertohavetheabilitytodeliverreadingsinall
ofthestandardnotations.
Chapter|10
473
Oneoftheearliestwaysofexpressingcolourwasdevelopedbyan
Americanartist,A.H.Munsell,wh
colourusingaseriesofpapercolou
rchips.Heclassifiedthecolours
accordingtotheirhue,lightnessan
dsaturation.Theprincipleofthis
approachisillustratedbytheso-c
alledcoloursolidasshownin
Fig.10.2
whichhasaspineoflightnessva
luesbasedonwhitetoblack.
Agivencolour(hue)aroundthecirc
umferenceofthesolidwillbecome
moresaturated(intense)thefurth
erthepointisonagivenradiusfrom
thecentralspine.
TheMunsellcolourchip-basedsystemremainsavailabletodayandcan
oftenbeusedforvisuallymatchingcoloursinmanyapplications.Forexam-
ple,forbakedproductcrustcolourusingalimitednumberofbrown-
colouredchips.Visually,matchingcrumbcolourwithMunsellchipsis
moredifficultduetotheeffectsofcellstructure.
Furtherreading
Billmeyer,F.W.,Saltzman,M.,1981.PrinciplesofColorTechnology,seconded
.
Wiley-
Interscience,NewYork,NY.
Hue
Lightness
Saturation
Black
White
FIGURE10.2
Schematicofacoloursolid.
474
BakingProblemsSolved
10.4HOWCANWEMEASURETHETEXTUREOFOURBREAD
ANDCAKES?CURRENTLY,WEUSEAHANDSQUEEZETEST
FORBREADANDAPPLYASCORETOTHERESULTS
Youcanmeasurebakedproducttextureusingtrainedassessorsorwith
instrumentation.Thelatterhastheadvantagethattheresultsareobjective,
withotherresults.Thevaluesmeasuredcanbelinkedtoascoringsystem
whenconsumerpanelshaveratedtheproductcharacteristicsbeing
measured.
Themostappropriateparametersforthetextureofbreadandcakepro-
ductsarefirmness(compressionofthecrumb)andresilience(springback
whenpressed).Thesearetheproductattributesmostcommonlylinkedwith
consumerperceptionoffreshnesswithbreadandcakecrumb.Inthecase
ofbreadandtheconsumersqueezetest,thereisanexpectationthatbread
productsareeasilysqueezed,buttheproductmustalsospringbackafter
compression.Springbackislessimportantwithcakecrumbbutsoftness
remainsakeyproperty.
Thereareanumberofdifferentinstrumentscapableofmeasuringcrumb
softnessandresilience.Textureanalysers,e.g.,StableMicroSystemsTA.
XTPlusTextureAnalyser,arefoundinmanyresearchandqualitytesting
laboratoriesusingdifferentprobesandfixturesaccordingtothetypeofmea-
surementrequired(
Cauvain,2017
).
thecommontechniquesforassessingbakedproducttextureisknownas
textureprofileanalysis(TPA)whichemploysadoublecompressionofthe
lishedby
Szczesniak(1963)
usingsensorypanelsandrelatedtoobjective
measurement(
Bourne,1978
).ThemeasurementsmadeusingTPAare
stronglycorrelatedtothebitingandchewingactionsofconsumers.
Fig.10.3
showsatypicalcurvefromaTPAtestonbreadcrumb.Althoughfirmnessis
thecomponentmostoftenmeasuredinassessingtexture,severalothercom-
minedbyusingrelevantsoftwarewiththeappropriateinstrumentsand
repeatedcompressionscanbemadeonthesamesampleenablingsample
adhesivenessandcohesivenesstobemeasured.
Whenusinginstrumentstoassessproducttexture(orindeedifusingsen-
soryassessment),itisimportanttotakethemeasurementinthesameloca-
tionofeachsampletoreducethevariationsinreadings(
Cauvain,1991
).
Theareasclosetothecrustshouldbeavoidedastheywillhaveadispropor-
tionatelylargeeffectonthetestresultsbecausetheywilltendtobelowerin
moisturecontentthanthebulkoftheproductcrumb.Itisalsothecasethat
manybakedproducts,especiallyfermentedproductsbakedinpans,tendto
haveanunevendensitydistributionthroughoutaslicecross-section;usually,
thecrumbdensityislowerinthecentreoftheproductthanitisneartothe
Chapter|10
475
crustduetocellcompressionresultingfromcentrecrumbexpansion.Both
theproductmoisturecontentandthesampledensityimpactonsensoryand
objectivetexturemeasurements,anditisadvisabletohavetherelevantdata
whenassessingtheresultsoftrials.
Oneinstrumentwhichmimicsthesqueezetestcarriedoutbyconsumers
istheBreadVSqueezeRig(
CauvainandYoung,2008;Cauvain,2017
).
Itenablestestingofpackagedandun-packagedloaves.Therigallows
repeatable,scientificanalysisofthefreshnessandappealofbread.Itconsists
ofVshaped,roundedfingers,whichareloweredontotheloafandthe
forcerequiredtocompressthebreadismeasured.Thelowertherecorded
forceandthehigherthevalueofspringiness,thefreshertheloaf.Thisnon-
destructivetestofferssimplicityinoperationandspeedofassessmentasthe
loafrequiresnosamplepreparationandcanbeanalysedwithinthepackag-
ing.Itenablestheassessmentofchangeswhichoccurinincreasedresistance
tocompression(firming)andalossofrecoverywhencompressed,i.e.,
decreasedspringiness,astheloafages.
References
Bourne,M.,1978.Textureprofileanalysis.FoodTechnol.32(July),62

66,72.
Cauvain,S.P.,1991.Evaluatingthetextureofbakedproducts.S.Afr.J.FoodSci.Nutr.
3(Nov),81

86.
andApplications,seconded.DEStechPublishingInc,Lancaster,PA.
Cauvain,S.P.,Young,L.S.,2008.BakeryFoodManufactureandQuality:WaterControland
Effects,seconded.Wiley-Blackwell,Oxford,UK.
Szczesniak,A.S.,1963.Classificationoftexturalcharacteristic.J.FoodSci.28(July

August),
385

389.
1
0
1
2
3
4
5
6
7
0510152025
Total travel of probe (mm)
Force (N)
FIGURE10.3
Typicaltextureprofileanalysiscurveforbreadcrumb.
476
BakingProblemsSolved
10.5HOWCANWEMEASUREBAKEDPRODUCTSHAPE
ANDVOLUME?
onthetypeofproductinvolvedandthepurposeforwhichthemeasurements
arerequired.
Simplebuteffectivemeasurementscanbemadeusingmeasuringtapesor
calibratedrulestoassessbreadheights,lengthsandbreadths.Fromsuch
measurements,acrudeassessmentofbreadvolumecanbemadebysum-
mingthevariousmeasurements.Inthecaseofpanbread,thewidthand
lengthdimensionswillbefixedbythepan,soitmaysimplybesufficientto
recordproductheighttoassessvariationsinqualityortheeffectsofingredi-
entorprocesschanges.
Themostcommonandlong-establishedmethodusedtomeasurebread
volumeistheonereferredtoasseeddisplacement.Inthistechnique,the
volumeofaboxoffixeddimensionsisrelatedtoagivenweightofseeds,
commonlyrapeseedthoughpearlybarleymayalsobeused.Toassessthe
volumeofaloaforotherfermentedproduct,asampleisplacedinthebox
withsufficientspacebetweenitandthewallsofthebox.Seedisthenintro-
ducedtofilltheemptyspacesurroundingthesampleuntilitisfull.Excess
seedisremovedbyscrapingtheuppersurfacelevelbeforetakingoutthesam-
plebeingmeasured.Theweightoftheseedremainingintheboxisrecorded
andcomparedwiththeweightofseedrequiredalonetofillthebox.Asthe
bulkdensityoftheseedisknown,thenanestimateoftheproductvolumeis
given.Theequipmentrequiredforthistypeofmeasurementisrelativelysim-
pleandcanbeeffectivelymechanised.Afewcommercialexamplesusingthis
techniqueexistbutoftentheequipmentishome-madeandrelatedtothepar-
ticulartestbakeryproductwhichmaybedifferentfromcommercialproducts.
Morerecently,themeasurementsofbakedproductsshapeandvolume
dataisbeingmeasuredusinglaserscanningwithsoftwarethatallows2-and
3-Dimagesoftheproducttobebuiltup(
Cauvain,2017
).Essentially,the
productprofileisassembledbytakingaseriesofverythinslicesthough
theproductandthenintegratingthevariousmeasurementstooutputsuch
characteristicsasvolume,height,breadth.Thesescanningdeviceshavethe
advantageofbeingnon-contactandsopotentialproblemswiththecrushing
ofdelicateproductsfromtheintroductionofseedsisavoided.Samplinghan-
dlingisalsokepttoaminimumwhichisanadvantagewithdelicateproducts
suchaslaminatedpastries.
Breadandcakesliceshapedatamayalsobecombinedwiththemeasure-
mentofinternalfeaturessuchascellstructure.Onesuchinstrumentis
C-Cell(
Cauvain,2017
)whichprovides48differentshapeandcellstructure
measurementsfromslicesofbreadandcake.
Chapter|10
477
Breadshapeandvolumedataareusuallygatheredonsampleswhich
havebeenremovedfromthelineforassessment,butwiththeadventofline-
ageanalysistechniques,itisnowpossibletocollectsomeofthesedata
onlineusinglaserscanners.Productsshapeandheightdatacanbemeasured
online,andwhileforsomeproduct(e.g.,liddedpanbread),theheightdata
canberelatedtoproductvolume,atruemeasurementofloafvolumeonline
isnotpossible.
Reference
andApplications,seconded.DEStechPublicationsInc,Lancaster,PA.
478
BakingProblemsSolved
10.6WHATISTHEPHOSPHATASETEST?
Phosphataseisanenzymeassociatedwithanimal,insectandmicrobialactivity.
Thephosphatasetestisoftenusedtoestablishwhetherornotaninsecthas
beenbakedinaproductorenteredaftertheproducthaslefttheoven.Itisvalid
forsampleswhichhavebeenstoredforalongtime.Evenafterseveralyears
storage,deadinsectsgiveastrongpositivereaction.
Thematerialsrequiredareasfollows:
Buffersolution
3.5-ganhydroussodiumcarbonate(analyticalgrade)and1.5-gsodium
bicarbonate(analyticalgrade)perlitre.(Thebuffermaybestoredforupto3
monthsinatightlystoppedcontainerofresistantglass.)
Substrate
Disodium
-nitrophenolphosphate.
Buffersubstrate
Transfer0.15gofthesubstratetoa100mLmeasuringcylinderand
makeupto100mLwiththebuffersolution.Thissolutionshouldnotbe
storedforlongperiods,butmaybekeptrefrigeratedforaweek.
Testingprocedure
Rinsetheinsectorfragmentswithwaterandthencrushwithaglass
rod.Aftermixingthefragmentswithafewdropsofwater,transfertoa
testtubeandmakewithrinsingswithwatertoabout1mL.Add5mLof
buffersubstrateand,aftermixing,incubateat37
C.Simultaneously,incu-
bateablankcomprising5mLbuffersubstrateand1mLdistilledwater.
After30minutes,comparethecoloursofthetubes.Normallythepres-
enceofphosphataseisindicatedbytheproductionofadarkyellowcolour
within30minutes.Weaklypositivet
ubesmayrequirelongerforthefull
colourtodevelop.Anegativeresultsuggeststhattheinsectorfragments
hadbeenheated.
Thedisadvantagesofthetestareasfollows:
Thetestvirtuallydestroysthesample.
Verysmallinsectsdonotgiveasufficientlystrongreaction.
Falsepositiveresultsmaybegiveniftheproductsampleisheavilycon-
taminatedwithmicroorganisms,e.g.,moulds.
Chapter|10
10.7WHATISTHEBOHNSSPOTTESTAND
WHATISITUSEDFOR?
TheBohnsspottestwasdevelopedforusewithsodacrackersandis
designedtotesttheiralkalinity.Thetestisbasedonapplyingachemical
indicatortoabrokensurfaceoftheproducts;thecolourofthespotwhich
showsindicatesthepHoftheproduct.
Thereagentisphenolredindicatorpreparedbydissolving0.02gphenol
tocoverotherrangeswithinthepHscale.Suchtestscanonlybeappliedto
productswhicharenotcoloured.Inadditiontoquicklyrevealingaproduct
pH,spottestsofthistypecanbeusedforidentifyingwhetherthecompo-
nentsofbakingpowdersarefullyreactedbecauseunreactedbakingpowder
componentswillshowasvividlycolouredspotsagainstthebackground
colouroftheproductmatrix.
Chapter11
What?
11.1WHATISTHEMEANINGOFTHETERMSYNERISIS
WHENAPPLIEDTOBREAD?
Syneresisisthenamegiventoaparticularphysicalorcolloidalchangethat
takesplaceinstarchandothergelsastheyage.Itiscausedbycrystallisation
oraggregationofpolymerscausinglossofwaterfromthesurfaceofcompo-
nents.Itiscommonwithsomestarchgels,particularlythosesubjectedto
freezingandthawing.Thereleasedwatermayevaporatetobeabsorbedby
othercomponentsbydiffusionorvapourphasetransfer,ormaybelostfrom
theproduct/componentcausingittodryoutandshrink.
Itisthechangeinstarchcrystallinitythatbringsaboutthestalingof
breadthatisadayortwooldcausingasensorychangeequivalenttoconvey
theimpressionthatthebreadcontainslessmoistureandthereforetohave
lostitsfreshness.Breadmayloseactualwaterduringtheprocessofstaling,
buttherearemanyotherchangesoccurringatthesametimewhichwill
accountforthedry-eatingqualitiesofthebread(
Cauvain,2015
).This
ofsyneresisandisaffectedbythetemperatureandhumidityunderwhich
thebreadiskept.
Ifaloafiskeptforseveraldays,thereisboundtobealossofwaterby
evaporation,butthiswaterwillnotbelostregularlyfromtheentireloaf.
Thelossisgreatestatthepartwhichisnearesttothecrust.Ithasbeen
shownthatthelossofmoisturefromthecentreofaloafisexceedinglysmall
andattheendof2weeksthemoistureinthecentreofaloafisalmostsame
asthebeginning.Itwouldmeanthatiftheoutsideportionoftheloafwas
cutofftheinteriorwouldbealmostasmoisteatingasaloafadayold.
However,thisisnotthecaseinsensoryterms.Aloafseveraldaysoldwill
bedryeatingandstaleequallythroughoutitswholestructure.Infact,there
Toillustratethis,prepareastiffstarchjellywhichcanbemadeand
allowedtostandforadayortwo.Thewaterwillpartiallyseparateoutand
willbeseenonthesurfacewhilstthegelatinisedstarchwillseemtohave
breadduringstorage.Thestarchwillseparateslightlyfromthewateritwas
481
BakingProblemsSolved.DOI:
http://dx.doi.org/10.1016/B978-0-08-100765-5.00011-4

2017ElsevierLtd.Allrightsreserved.
insoluble,thoughapparentlyitdoesnotmeanthatthesmallamountofwater
thathasseparatedoutwillbeevaporated.Thebreadparticlesbeingdenser
willbehardertomixwithsalivainthemouthsothatasensationofdryness
andadifficultyinmasticatingthebreadareexperiencedandmakeusthink
thatthebreadisdry.
Anotherpointaffectingtheconditionofthestarchisthetemperature
atwhichthebreadisstored.Breadstoredat4

Cstalesmorerapidlythanthat
storedatroomtemperatureorunderfrozenconditions.Atalowtemperature
of
2
5

Cstalingdoesnotoccur,thoughtheactoffreezingandthawingbread
ustheequivalentof24hoursstorageatambient(
PenceandStandridge,1955
).
References
Cauvain,S.P.,2015.TechnologyofBreadmaking,thirded.SpringerPublishingInternational
AG,Switzerland.
Pence,J.W.,Standridge,N.N.,1955.Effectofstoragetemperatureandfreezingonthefirming
ofacommercialbread.CerealChem.32,519

526.
482
BakingProblemsSolved
11.2WHATISASUPER-SATURATEDSOLUTION?
Sugarissolubleinwater.Wateristhereforethesolventandsugaristhesolute.
Whenasolventisfilledwiththesubstanceinsolutionsothatitcannotdissolve
anymoreitissaidtohaveformedasaturatedsolutionofthatsubstance.To
illustratetheprincipleofsuper-saturation,startbydissolvingasmuchsugaras
possibleintosomewaterinabeaker.Afteraddingsugarandconstantlystirring
themixtureforsometime,youwillfinditimpossibletodissolveanymore
sugar.Ifyoudoaddmore,itwillremainundissolvedandsinktothebottomof
thebeaker.Ifthecontentsofthebeakerarenowgentlyheated,thesugaratthe
bottomwilldissolve,andifmoresugarisaddedtothemixture,itcanalsobe
dissolved.Thisprocesscanbecontinueduntilonceagainthewatercandis-
solvenomoresugar.Againthewaterissaturatedwithsugar.Itisobviousthat
thesameamountofhotwaterhasmoresugarinsolutionthanitcouldhold
whencold.Ifthesolutionisthenallowedtocoolwithoutstirringtothesame
temperatureasthecoldsolution,thepreviouslywarmedsolutionwillcontain
moresucrose,itwillactuallybeacoldsuper-saturatedsolution.
Ifaquantityofwateratboilingpointinwhichisdissolvedasmuchsugar
asitcanholdiscontinuedtobeheatedthenasthesolutionboilswateris
drivenoffbuttheamountofsugarremainsthesame.Thisresultsinahot
super-saturatedsolution.Thelongerthesolutionisheated,thelesswater
remainsandthegreaterthedegreeofsuper-saturation.Thiscausesarisein
temperaturewhichcontinuestoincreaseuntilnotonlyisallthewaterdriven
Chapter|11
11.3IHAVEHEARDTHETERMSGLYCAEMICINDEXAND
GLYCAEMICLOADUSEDWHENDESCRIBINGBAKERY
PRODUCTS.WHATARETHEYANDWHATISTHE
Bothtermsareusedtodescribethewayfoodisdigestedbythebody.The
glycaemicindex(GI)ofafoodmeasuresitsimmediateeffectonbloodglu-
coselevelsoverashortperiodoftimefollowingingestionofafood.Itisthe
bloodglucoseprofileof50gofavailablecarbohydrateinatestfoodcom-
paredwith50gofglucose.Ontheindex,glucoseistakenas100sinceit
causesthegreatestandmostrapidriseinbloodglucose
allotherfoodsare
ratedincomparisontoglucose.
GIisameasureofhowquicklyaparticularfoodtriggersariseinblood
sugarlevelandtheratebloodsugarleveldropsoff.Itisaphysiological
measureofhowfast,andtowhatextent,acarbohydratefoodaffectsblood
glucoselevels.Thetypeofcarbohydrateinafoodinfluencesbloodsugar
levels.
GIhasitslimitationsinthatitcanonlybeaccuratelymeasuredfroma
bloodsample.Itonlymeasurestheavailablecarbohydrateandingredients
thatreducedigestabilitysuchasresistantstarchesarenottakenintoaccount
astheyaredigestedlaterinthelowerintestine.Processingcanchangea
foodsGIvalue.Fat,proteinandalowerpHinafoodallreduceproductGI.
ThetablebelowshowstheGIcategoriesthatfoodscanbeplacedin(the
sugarglucosehasarankingof100).
GIRating
Medium36
Theglycaemicload(GL)ofafoodisanexpressionofhowmuchimpact
orpowerthefoodwillhaveinaffectingbloodglucoselevels.Itiscalculated
bytakingthepercentageofthefoodscarbohydratecontentperportionand
multiplyingitbyitsGIvalue
%carbohydrateperportion
100
GListhusameasurethatincorporatesboththequantityandqualityof
thatofabagel(equivalenttothreeslicesofbread)ismorethan30.Insimple
termstheGIindicatestheextenttowhichafoodwillraisebloodglucose
levels,whereastheGListhepowerorpushbehindtheGI.
AcomparisonoftheGIandGLforsometypicalbakeryfoodsisgiven
below.
ProductCarbohydrateconcentrationGIGL(typicalportion)
Whitebread4540
Wholemealbread4750
,
70(1slice)
Crackers6080
,
5(1biscuit)
Shortbreadbiscuit6855
,
5(1biscuit)
givesusafeelingoffullness.Afoodwhichishighincarbohydrateswith
lowGItakelongertodigestandsogivethefeelingoffullnessforalonger
periodoftime.Thetermhascometotheforemorerecentlywiththecon-
cernsoverobesityandthedrivetowardshealthiereating.Anindexof
Holt,1998
)andexamplesaregivenbelow(com-
paredwithwhitebreadwithindexof100),butthecredibilityofthis
Wholemealbread157
Cake65
Cookies120
Croissant47
Crackers127
Reference
Holt,S.(1998)
,May,pp.1,12

14.
.
What?
Chapter|11
485
11.4WHATAREPRO-ANDPREBIOTICSANDHOWCAN
THEYBEUSEDINOURBREADPRODUCTS?
Aprobioticisalivingmicroorganismconsideredbeneficialtothehumanbody,
particularlyinthefunctioningofthegut.Thesebeneficialbacteriaarefound
naturallyinvariousfermentedfoods,e.g.,yoghurt,butdonotsurviveheatand
sowouldbedestroyedbythehightemperaturesemployedinbakingandso
havenosignificantroleinthetechnologicalformulationofbakeryproducts.
beneficialbacteriaandenhancethebenefitsofprobiotics.Bifidobacteria
(goodbacteria)contributetohealthbyenablingthedigestivesystemtopro-
duceshortchainfattyacidsthatlowerthepHinthedigestivesystem.This
inturnhelpstoincreasetheabsorptionofthemineralscalciumandmagne-
siuminthebody.Theintestinecontains70

80%ofthebodysimmunecells
fibresarefoundnaturallyinplantsandcan,insomecases,beproducedby
enzymaticconversionfromsugar.Theypassunalteredthroughthestomach
andarefermentedbygutmicrofloraandselectivelystimulatethegrowthand
activitiesofbacteria.Thehighmolecularweightsugarsreferredtoasoligo-
saccharidesdominatethiscategoryandtheyincludefructooligosaccharides
(FOS),inulin,arabinogalactansandlactulose.
FOSandinulinareparticularlyfavouredbylactobacilliandbifidobacter-
iainthegut.Lactobacillicanconvertsugarsintolacticacid,inhibitingthe
proliferationofcertainharmfulbacteria,whilealsoloweringthepHofthe
Inulinandoligofructosearemadefromchicoryroot(goodsource)and
arealsofoundinartichokes,leeks,onionsandgarlic.Intheirpureformthey
haveacleantasteandarehygroscopic(preventwaterloss)andwhenusedin
cerealbarshelpkeepthemsoft-easting.Theyincreasebeneficialbifidobac-
triainthecolonbycreatingabarriereffectthusreducingthepotential
impactofbadbacteriasuchassalmonellaandclostridia.
Theuseofprebiotics,suchasinulin,inbreadproductshasbeenpartofa
poratedatlowlevelsinbakeryformulations.Thestructureandcolourofthe
productintowhichtheyareincorporatedshouldbemonitored.
Ifyouaregoingtouseprebioticingredientsyoushouldcheckthattheyare
approvedforuseinyourgeographicallocation.Youshouldalsocheckthe
Furtherreading
Myers,S.(2006).TheFunctionalityofProbioticsandPrebiotics:BringingLifetoFunctional
FoodsandBeverages.
http://www.naturalproductsinsider.com/articles/06oct16feat02.html
.
486
BakingProblemsSolved
HYDRATIONANDHYDROLYSIS?WHATISTHEIRRELEVANCE
TOTHEMANUFACTUREOFBAKEDGOODS?
Hydrationandhydrolysisrefertoreacti
onswhichinvolvewater.Hydrationis
theadditionofwatertoasubstance,wher
eashydrolysisindicatesthosechemical
changesinwhichwaterreactswithasubs
tancetoyieldtwoormoreproducts.
Hydrationisthemorefamiliarterminbakingbecauseitisanecessary
firststepintheformationofdoughsandbatters.Inbreadmaking,thehydra-
tionoftheflourproteinsduringmixingaidstheformationofthedisulphide
bondswhichareanimportantelementofdoughdevelopment.Hydrationof
theflourproteinsalsooccursinthemanufactureofbiscuits,cakesandpas-
islimitedbyrecipeandprocessfactors.
Theprocessesofhydrationandhydrolysisarebestunderstoodbyconsid-
thegranulesandthisispartoftheprocessrelatedtothewaterabsorption
capacityoftheflour(see
Section2.2.3
).Inwheatflour,itisthedamaged
starchwhicharemostrapidlyhydrated,andtheyabsorbaboutfourtimesof
waterthatwillbeabsorbedbytheundamagedgranules(
Cauvain,2015
).
Thehydrationofstarchleadstohydrolysis.However,forthehydrolysisto
occurwithwheatstarch,both
alpha-
and
beta
-amylaseenzymesneedtobe
present.Inmostcases,bothenzymesarepresentandsoareabletocatalysethe
hydrolysisreaction.Thefullhydrolysisreactionmaybedescribedasfollows:
Starch
1
water

inthepresenceofamylaseenzymes

yieldsglucose
1
fructose
Theaboveequationisasimplifiedversionofacomplexreactionwhich
takesplaceinthemanufactureofbakedproducts.Theheatwhichisintro-
ducedduringbakinginactivatestheenzymesandoverallprocesstimesare
tooshortforthefullconversionofallofthestarchtosugars.Thisisjustas
wellbecausestarchisanimportantcomponentinbakedproductstructure,
starchisnothydrolysed,andinbakedproducts,thereareaseriesofsub-
whicharethedextrinswhichcangiverisetoproblemswithbreadquality.
Reference
Cauvain,S.P.,2015.TechnologyofBreadmaking,thirded.SpringerPublishingInternational
AG,Switzerland.
What?
Chapter|11
487
11.6WHATISMEANTBYTHETERMGLASSTRANSITION
TEMPERATUREANDWHATISITSRELEVANCETOBAKING?
Insimpleterms,theglasstransitiontemperaturereferstothetemperature
belowwhichafoodwillbestable,i.e.,notchange,whenstoredforlongper-
iodsoftime.Itiscommonlyreferredtobythenotation
T
g
.Theglasstransi-
tiontemperatureofaparticularfoodisuniquetothatfoodandisdirectly
relatedtoitscomposition.Thestabilityofafoodreferstobothitsphysical,
chemicalandmicrobialcondition.
Theconceptofglasstransitioncomesfrompolymerscience.Thecompo-
sitionofbakeryfoodsisamixtureofcomplexpolymers(e.g.,thestarchand
proteins).Aboveits
T
g
,abakeryfoodisconsideredtoexistinarubbery
state.Theuseofthewordrubberydoesnotrefertothetextureofaproduct
butindicatesthatitisunstableandlikelytoundergochangeduringstorage;
thestalingofbreadisanobviousexampleastheproductincreasesinfirm-
nesseventhoughtheremaybenolossinoverallmoistureduringstorage
(
Cauvain,2015
).Ifthetemperatureatwhichthebreadisstoredislowereda
pointiseventuallyreachedatwhichfirmingstops,thisisthe
T
g
forthat
breadandtheproductisnowsaidtobeinaglassystate.Intheglassystate,
theproductwillhaveaverylongshelf-lifebecausethewaterintheproduct
iseffectivelyimmobilisedintheproduct.Materialsmayhaveanumberof
glassystatesdependingonhowtheglasshasbeenformed(
Roos,2007
).The
rateatwhichabakeryproductcoolstoreachits
T
g
hasasignificanteffect
onhowthewatermoleculesbecomeimmobilisedintheproductandthis
howitwillbehaveinstorage.
Manybakeryproductsarestoredandconsumedattemperaturesatwhich
theyexistinarubberystateandthislimitstheirmicrobialandsensoryshelf-
lives.Thisknowledgeofaproducts
T
g
andinparticularhowtomanipulate
itthroughreformulationtoachieveamorestablestoragestatehassignificant
practicalimplicationsforthedevelopmentofbakeryproducts.
Oneofthedifficultiesfacingbakersisthattheglasstransitionconceptis
noteasilyappliedinthepracticeofproductreformulation.Morereadily
appliedisthemeasurementorcalculationofwateractivity[orequilibrium
relativehumidity(ERH)],anditisthispropertythatfindsmostpracticaluse
inbaking(
CauvainandYoung,2008
).
References
Cauvain,S.,2015.TechnologyofBreadmaking,thirded.SpringerPublishingInternational,
Switzerland.
Cauvain,S.P.,Young,L.S.,2008.BakeryFoodManufactureandQuality:WaterControland
Effects,seconded.Wiley-Blackwell,Oxford,UK.
Roos,Y.R.,2007.Wateractivityandglasstransitio
n.In:Barbosa-Canovas,G.V.,FontanaJr.,A.J.,
Schmidt,S.J.,Labuza,T.P.(Eds.),WaterActivityinFoods:FundamentalsandApplications.
BlackwellPublishing,Oxford,UK,pp.29

48.
488
BakingProblemsSolved
11.7WHATDOESTHETERMMVTRMEANWHENAPPLIED
TOPACKAGING,ANDWHATISTHERELEVANCETOBAKED
PRODUCTS?
MVTRstandsformoisturevapourtranspirationrate,andwhenappliedto
packagingmaterial,itisameasureoftherateatwhichmoisturepasses
24hoursatatemperatureof38

Cinanatmosphereof90%relativehumid-
ity.IntheUSA,asimilartermwatervapourtranspirationrateisusedand
isexpressedingramsper100squareinchesper24hoursat100

F
with90%relativehumidity.Forexample,a25

mgaugebasiccoextruded
polypropylenefilmmighthaveaMVTRof5g/m
2
/24hoursat38

C.
Moisture-impermeablefilmswouldhaveazeroMVTR.
Packagingisusedforbakedproductstopreserveoptimumproductqual-
ityandpreventcontaminationbymicroorganismsorothermeans,toprotect
themfromphysicaldamageandtomakethemattractiveandtodeliveringre-
dient,nutritionalandotherinformationtoconsumers.
Whenpurchasingpackagingmateria
lsforbakedproducts,thebakerhas
ventmoistureescapingorenteringthepack.Inthecaseofbiscuits,usinga
moisture-impermeablewrapperisa
boutrestrictingtheriskofmoisture
beingabsorbedfromtheatmospherebytheproductwhichcouldresultin
character.Theconsumerwouldperceivethissofteningasastalingofthe
product.
Thepermeabilityofpackagingmaterialscanaffectmoisturemigrationin
theproductbyaffectingtherelativehumidityoftheatmospheresurrounding
theproduct(
CauvainandYoung,2008
).Packagingmaterialswithlow
MVTRcreatehighrelativehumiditiesinthepackatmosphere,andthis
TheimpactonproductqualitywilldependonfactorsliketheERHofthe
productsinceproductswithlowERHslosewaterlessreadily.
Packagingfilmscanbeusedtokeeptheproductskeyattributesfora
longerperiodasthetypeusedinfluencestherateofmoisturemovement
bothwithinandfromtheproduct,andthereforetheproductfreshness.An
exampleisbreadpackagedinamoisture-impermeablefilm,theproduct
reachesequilibriumfairlyquickly,withthecrustsofteningbutwithlittle
lossofmoisturefromtheproductoverall.Thissituationissuitedtopan
breadcharacterbutnottocrustybreads.Incrustybreads,someextensionof
somemoisturetoescapefromtheproducttothesurroundingatmosphereso
thatthereisalwaysamoisturegradientthroughouttheproduct.Thenegative
What?
Chapter|11
489
sidetothisapproachisthatthecrumbmoisturecontentfallsrapidlytoa
levelthatisorganolepticallyunacceptable.Aperforatedfilmismostcom-
monlyusedtoslowdownmoisturelossfromcrustyproductswhiletryingto
Fig.11.1
).
Thepermeabilityofthewrappermaybedeliberatelyincreasedtomain-
taintheeatingqualityoftheproduct.Forexample,semi-permeablewrappers
maybeusedtopreventpastryproductsfromreachingequilibriumwiththeir
.
Thevolumeofairenclosedinthepackhasasignificantroletoplayas
theamountofmoisturethatcanevaporatedependsonthemassofmoisture
thatcanbeheldbytheairinthepack.Fluctuatingtemperatures,e.g.,in
transportorstorage,cancreatesignificantproblemsasthemassofwater
thattheairiscapableofholdingvarieswithtemperatures.Wrappedproducts
movingfromhightolowtemperaturesareatriskfromcondensationwith
subsequentqualitylossesandincreasedrisksofmicrobialgrowth.
References
Cauvain,S.P.,Young,L.S.,2008.BakeryFoodManufactureandQuality:WaterControland
Effects.Wiley-Blackwell,Oxford,UK.
Stollman,U.,Johansson,F.,Leufven,A.,1996.Packagingandfoodquality.In:Man,C.M.D.,
Jones,A.A.(Eds.),ShelfLifeEvaluationofFoods.BlackieAcademic&Professional,
London,UK,pp.40

51.
FIGURE11.1
Perforatedfilmwithcrustybreadproduct.
490
BakingProblemsSolved
11.8WHATISMEANTBYTHETERMMODIFIED
ATMOSPHEREPACKAGINGANDHOWCANWEUSETHIS
APPROACHINTHEPRODUCTIONOFBAKEDPRODUCTS?
Modifiedatmospherepackagingisthetermusedtodescribethewaythe
atmospheresurroundingaproductinitspackagingmaterialischangedfrom
airtosomeothercombinationofgasestoextenditsmould-freeshelf-life
(MFSL).Itisalsoknownasgasflushing.Thegasesemployedareusually
carbondioxideornitrogen,commonlyasamixtureofthetwo.
Thisformofpreservationissuitableformanytypesofbakedproduct,
andwhilstithascostimplications,itdoesnotaffectproductflavour,aroma
orappearance,anditmaynotneedtobedeclaredasaningredientonthe
productlabel.Carbondioxidehasaninhibitoryeffectonthegrowthofaero-
bicmicroorganismssuchasmoulds.ThegreatertheconcentrationofCO
2
,
thegreateristhepreservationeffect(
Cauvain,2015
).Insomecases,itcan
giveupto400%additionalshelf-lifedays.Itisoftenusedforhighervalue
products.Itisknownthatsomemouldsaremoreaffectedthanothers,e.g.,
thosepresentonshortershelf-lifeproductssuchasbreadsarelesssensitive
thanthosepresentoncakeswithalowerERH.
Fig.11.2
showsthetypical
increasesinMFSLfordifferentbakeryproductsatdifferentconcentrations
ofCO
2
.Asthepackagingatmosphereisgaseous,ithastheadvantageofpro-
tectingallsurfacesoftheproduct.
Theinertgasnitrogencanalsobeusedastheflushinggasthoughitdoes
notexhibitanyanti-mouldactivity.Itisthefactthatthenitrogenreplaces
theoxygenandcausestheatmospheresurroundingtheproducttobecome
anaerobicthatinhibitsmouldgrowth.Inthiscase,thepercentageofnitrogen
intheheadspacemustbeatleast99%byvolumeandgreatcaremustbe
takenwiththesealsandwrappingmaterialtoensurethatnooxygen(asair)
canenterthepack.NitrogenismorecommonlyusedalongwithCO
2
topre-
ventthepackagecollapsingasCO
2
isabsorbedintotheproduct.
0
100
200
300
400
500
020406080100
Average CO
2
concentration (% by
volume)
Increase in mould-
free shelf-life %
Madiera cake
pies
Rye bread, bread
rolls
FIGURE11.2
Increaseinmould-freeshelf-lifeofvariousbakeryproductspackagedindiffer-
entconcentrationsofCO
2
.
What?
Chapter|11
491
integrityofthesealsofthepackagingandthepermeabilityofthepackaging
materialwhichisoftenlaminated.Iflongerincreasesinshelf-lifeare
required,thenagasimpermeablematerialshouldbeused.
Reference
Cauvain,S.P.,2015.TechnologyofBreadmaking,thirded.SpringerPublishingInternational
AG,Switzerland.
492
BakingProblemsSolved
11.9WEHAVEHEARDPEOPLEREFERRINGTOSYNERGYIN
THEUSEOFINGREDIENTSINBAKINGPROCESSES,WHATIS
THISPROCESSANDCANYOUIDENTIFYANYEXAMPLES?
Synergycanbesaidtohaveoccurredwhenthecombinedeffectofacom-
positeadditionoftwoormoreingredientsisgreaterthanthesumoftheindi-
vidualcontributions.Insimpleterms,itislikesayingthatifeachoftwo
ingredientscontributetwounitsofeffectthentheendbenefitofaddingthem
incombinationisgreaterthanfour,inotherwordsitisacaseof
2
1
2
5
5.Inmanycaseswhenyouencounterthetermbeingusedinbak-
ingparlance,itisbeingusedtodescribeadditiveeffectswhen2
1
2
5
4.
Thetermismostcommonlyusedinconnectionwiththemixtureofcom-
ponentsthatcharacterisebreadimproversanddoughconditionersandmost
usuallylinkedwithdoughorbreadqualityimprovementsintermsofloaf
volumeandcrumbsoftness.
Awell-documentedinstanceofsynergyisthatrelatedtotheadditionof
ascorbicacidandpotassiumbromateinthemanufactureofbread.Thepast
useofpotassiumbromateandascorbicacidintheChorleywoodbreadpro-
cess(
CauvainandYoung,2006
)wasanexampleofsynergyinthatthecom-
individualreactionswithdifferentthiolgroupsoftheflourproteinsthatwere
uniquetoeachofthetwooxidants.Itisalsoknownthattheapplicationof
partialvacuumduringmixingwiththeChorleywoodbreadprocesshada
directimpactonthesynergyanddifferentmixerscanalsoinfluencethe
degreeofsynergybychangingtheavailabilityofoxygen.
Anotherexampleofsynergyistheincreasedeffectivenessofantimicrobial
ingredientswhenthepHofabakeryproductislowered.Inthiscase,the
microorganismsareconfrontedwithso-calledhurdleeffects.Theopportu-
nitiesforusingpHtocontrolmicrobialgrowthonbakeryproductsarerela-
tivelylimitedbecausemostbakedproductshavepHsintherange5.0

7.5,
andinthisrange,mostmicroorganismswillremainactive.However,thecom-
binationofpreservativeandpHcanbeveryeffective.Forexample,
Cauvain
andYoung(2008)
citedatashowingthatincake(92%ERH)treatedwiththe
addition1000-ppmsorbicacid,loweringthepHfrom7.0to5.0increasedthe
MFSLoftheproductfromaround5to21days.Theadditionofthesorbic
acidalonehadonlyincreasedtheshelf-lifeby1day(i.e.,4to5days).
References
Cauvain,S.P.,Young,L.S.,2006.TheChorleywoodBreadProcess.WoodheadPublishingLtd,
Cambridge,UK.
Cauvain,S.P.,Young,L.S.,2008.BakeryFoodManufactureandQuality:WaterControland
Effects,seconded.Wiley-Blackwell,Oxford,UK.
What?
Chapter|11
493
11.10WHATAREPOLYOLSANDHOWARETHEYUSED
INBAKING?
Polyols,orpolyhdricalcoholstousethefulldescriptor,isatermusedto
coverawiderangeofsugaralcohols,thatisingredientsderivedfromthe
reductionofsugars(bothmonoandpolysaccharides).Theyhavesomecom-
monattributesincludingthattheyhavefewercaloriespergramthansugar
andarenotassociatedwithtoothdecay.Becauseofthesetwoproperties,
polyolsareoftenseentobealternativestosugars,especiallyincakesand
biscuits,especiallyinthecontextofcaloriereducedproducts.Thissome-
timesleadstotheclaimthatpolyolscanbeusedasfat-replacers,butinprac-
tice,theysupplynoneofthefunctionalityoffatinbakedproducts.
Amongtheirotherpropertiespolyolshaveacoolingeffectonthetongue
anddonotreadilytakepartinMaillardbrowningreactions.Aparticularly
importantpropertyofsomeofthepolyolsisthattheiradditionwilllowerthe
wateractivityofaproductwiththebenefitsofincreasingtheMFSLofpro-
ducts.Forexample,sorbitolsolidsaretwiceaseffectiveassucrose(weight
forweight)atloweringproductwateractivityandsomaybeusedincake
formulationstoincreaseambientshelf-life.
Polyolsaffecttheglasstransitiontemperatureofbakedproductsandso
maybeusedinproductformulationsforfrozenproductstominimiseproduct
changesastheresultoffromstorageortoencouragechangesinproducteat-
ingcharacter,see
Fig.11.3
(
Cauvain,1998
).Polyolshaveasignificant
impactonstarchgelatinisationcharacteristicssothatwhenusedincake
makingtheywillaffectproductshape.
Oneofthenegativefeaturesofpolyolsandtheiruseisthathighlevels
cancontributealaxativeeffectinthehumanbody.Forthisreason,their
0.2
0.25
0.3
0.35
0.4
0.45
0.5
020406080100
Frozen storage time (days)
Cake crumb cohesiveness
Sucrose
Lactitol
Sorbitol
FIGURE11.3
Effectpolyolsandfreezingoncakecrumbliness.
494
BakingProblemsSolved
levelsofdailyconsumptionmaybesubjecttomandatoryandvoluntary
restrictions,especiallyinproductsaimedatchildrenortheelderly.You
shouldcheckthepositionforyourownpartoftheworldbeforeundertaking
anyproductdevelopmentasthismaylimitthepracticallevelsofaddition
thatyoumightmake.Rememberthatifyouusemorethanonepolyol,itis
thetotaloftheiradditionwhichmustbeusedinmakinganyestimatesasto
likelydailyconsumption.
Examplesofpolyolsinclude:

Sorbitol,2.6calories/g,approximately50

usedincakestolowerwateractivity(seeabove),availableasan
aqueous-basedliquid.

foods.

cakesandchocolate.

Isomalt,2.0calories/g,approximately45

usedinwafers.

Lactitol,2.0calories/g,approximately30

usedincakes,cookiesandchocolate.

Mannitol,1.6calories/g,approximately50

usedinchocolateflavouredcoatings.

Erythritol,0.2calories/g,approximately60

usedinlowcaloriefoods.

Hydrogenatedstarchhydrolysates,3.0calories/g,approximately25

50%

biscuits.

nessofsucrose,usedinfrostingsandfillings.

Trehalose,occursinnature(e.g.,honey),commerciallyderivedfrom
infrostingandfillings,claimedtohavecryoprotectanteffectonprotein
structuresandcellstructureswhichmaybedehydratedorfrozen.Thelat-
terclaimiscommonlylinkedwithfreezingbakersyeast.
Reference
Cauvain,S.P.,1998.Improvingthecontrolofstalinginfrozenbakeryproducts.TrendsFood
Sci.Technol.9,56

61.
Furtherreading
What?
Chapter|11
495
11.11WHATISACRYLAMIDE?WHEREDOESITCOMEFROM
ANDHOWDOWELIMITIT?
Acrylamideisaneuoptoxinsuspectedtobeacarcinogeninanimalsand
humans.Itisformedasaresultofsidereactionsthattakeplaceinstarchy/
highcarbohydratefoodsalongsidetheMaillardreactionandinthepresenceof
asparagines,areducingsugar(suchasglucose)andheat(baking,fryingor
toasting).Asparagineisanaturaloccurringaminoacidpresentinsome
protein-richrawmaterialsofplantoriginwhichincludesgrainsandflours.
Thelevelsofacrylamidewhichforminbakedproductsareverylowandonly
occurattemperaturesabove120

C.Thismeansthananyacrylamidewhichis
presentismostcommonlyassociatedwiththecrustofbakedproducts.
Itcanbelimitedbycontrollingtheformationoftheprecursorstoacryl-
amide(mainlyasparagines)byalteringthemechanismsbywhichitis
formed;e.g.,byreducingthetemperaturesandtimeinbakingorreducingor
replacingsomeoftheacrylamide-promotingingredients,suchasthereduc-
ingsugars,intheformulation.Itisclaimedthatwhenusingsometypesof
processing,suchasprolongedfermentation,acrylamideformationcanbe
minimised.Introducingsteaminthefinalpartofbakinghasbeenshownto
reducetheformationofacrylamide(
www.heatox.org
).Ithasalsobeen
showntobelimitedbytheadditionofingredientssuchasfreeglycine
(anothernaturallyoccurringaminoacid),butitshouldbenotedthatadding
highquantitiesofglycinetobreaddoughmayleadtoreducedyeastactivity.
Someingredientmanufacturershavedevelopedenzymepreparations
basedonaspariginasefrom
Aspergillusniger
or
Aspergillusoryzae
orbacte-
riaaspartofanacrylaimdereductionstrategy(
).These
enzymesconvertasparaginesintoanothernaturallyoccurringaminoacid
calledaspartateorasparticacid.Thismeansthattheasparagineisnolonger
availablefortakingpartintheacrylamide-formingreaction,anditisclaimed
thatsuchenzymesdonotaffectthenutritionalproperties,browningortaste
aspectsofproducts.
IntheEU,theConfederationoftheFoodandDrinkIndustries(CIAA)
hasreleasedaseriesofToolboxguidesadvisingmanufacturersonhow
theycanreduceacrylamideinthemanufactureoffoods(
http://www.food-
drinkeurope.eu/publications/category/toolkits/
).
Reference
deBoer,L.,Meermans,C.E.M.,Meima,R.B.,2005.Reductionofacrylamideformationinbak-
eryproductsbyapplicationof
Aspergilliusniger
asparaginase.In:Cauvain,S.P.,Salmon,
S.E.,Young,L.S.(Eds.),UsingCerealScienceandTechnologyfortheBenefitof
Consumers.WoodheadPublishingLtd,Cambridge,UK.
496
BakingProblemsSolved
11.12WHATISOSMOTICPRESSUREANDWHATISITS
RELEVANCETOBAKING?
Osmoticpressurereferstotheconcentrationofsolubleparticlesintwosolu-
tionswhichareseparatedbyapermeablemembrane;thisisamembrane
whichcanallowthefreeinterminglingofthetwosolutions.Thisintermin-
glingwilloccuriftheconcentrationofsolubleparticlesononesideofthe
membraneisdifferenttothatontheotherside.Thenaturalmovementisfor
theparticlesintheconcentratedsolutiontomovethroughthemembraneto
thedilutersolution.Eventually,theconcentrationsofthetwosolutionswill
becomeequal,andatthatmoment,theosmoticpressurewillbecomezero.
Thusosmoticpressurecanonlyexistwhentheconcentrationofparticlesin
thetwosolutionsareunequal.
Osmoticpressureisparticularlyrelevanttoyeastfermentation.Thecon-
tentsoftheyeastcellarecontainedwithinadoublecellwall;thisisthe
equivalentofthemembranedescribedabove.Therearemanysolublemateri-
alsdissolvedwithinthewaterinsidetheyeastcellandthuswhencellsare
placedincontactwithothersolutionswhichhaveadifferentconcentration
entwillaffectthemovementofmaterialsthroughtheyeastcellwallmem-
branesineitherdirectionandindoingsocanaffectboththeintegrityofthe
cellsandtheirefficacy.Theprincipleisillustratedin
Fig.11.4
.
Themostpracticalimplicationsofosmoticpressureinbakingarerelated
totheimpactofsaltsandsugarsonfermentation.Themostcommonly
observedeffectsaretheliquificationofyeastifitcomesintodirectcontact
withundissolvedsaltsandsugars.Becauseoftheiraffinityforwater,saltsand
sugarswilldrawthewaterfromwithinthecells(i.e.,thereisahighosmotic
pressure)andapoolofliquidforms.Thepracticalconsequencesofsuchan
interactionisthattheintegrityandvitalityoftheyeastcellsaredisruptedwith
subsequentnegativeeffectsinbreadmaking.Eventheconcentrationofsalts
andsugarsinthewaterofthedoughformulationcanhaveanegativeeffect
onfermentationbutbecauseofthedilutiontheeffectisnotasdramatic.
Water
Water
Yeast cell membrane
FIGURE11.4
Principleofosmoticpressureacrosstheyeastcellmembrane.Blackdotsrepre-
sentsolubleparticlesinwater.Left,equalconcentrations

Noosmoticpressures;middleand
right,unequalconcentrationswithdirectionofwaterflowacrossthemembraneasindicated.
What?
Chapter|11
497
11.13WHATISRESISTANTSTARCH?
Starchisacarbohydratewhichconsistsoflongchainsofglucosemolecules
11.14WHATARETHEORIGINSOFTHECOTTAGELOAF?
thecottageloaf.Itsoriginsarenotknownforcertain.Therewouldnot
seemtobeanyparticularreasonwhyaloafshouldbemadefromtwo
mouldeddoughpiecesandthenassembledoneontopoftheotherbefore
baking.Loavesmadeinthisfashionhavebeenknownforhundredsofyears.
InancienttimesaloafcalledaNastus,wasmadeinthisformand
Suchwasthesize,OMaster,oftheNastus,
Alargewhiteloaf.Itwassodeep;itstop
Itssmellwhenthatthetopwasliftedup,
Roseup,afragrancenotunmixedwithhoney.
Althoughtherewouldnotseemtobeanymisunderstandingnowadaysas
towhatismeantbyacottageloaf,thereseemslittleavailableinformationas
ago,whenbakingwaslargelydoneathome,andwhereaccommodationwas
limitedandfamilysizeslargerthantoday,thehousewifehadtoinventsome
Byplacingonecakeofbreadontopofanother,keepingthetopsmaller
thanthebottomsothatitwouldnottoppleoverintheovenorcomeinto
contactwiththewallsoftheoventhehousewifecreatedasingleloafcom-
posedoftwocakesofbread.Thetwocakeswereheldtogetherbyadeep
indentation(perhapsbythebakerselbow)madeverticallydownwardsfrom
theupperintothelowerportion.
Thisofcourseissupposition,butinallprobability,itwaslackofspace
intheoventhatfirstmadethecottagerexperimentwithoneloafontopof
anotherandsoevolvedwhateasilymightbecalledthecottagersloaf,
whichhasnowbecomeacottageloaf.Avariationoftheloafisonecalleda
cottagebrickwheretwobrick-shapeddoughpieceswerebakedontopof
theother.
Thecuttingornotchingoftheproductisasmuchaboutcontrollingloaf
shapeasitisaboutprovidingadistinctiveappearance(see
Fig.11.5
).
Bothversionsofthecottageloafarenotoriouslydifficulttomake.Each
part,headandbase,isprocessedseparatelyandthencombinedbeforefinal
aretobejoinedareflatwiththepressureofjoiningthepiecesappliedright
throughthebase;oftenpunchingtheendofathinpastryrollerthoughthe
twopieceswillmakeaneffectivejoin.Intheproverandtheearlystagesof
baking,thepressurebuild-upinthebasedoughcancausethewholeloafto
toppleoverifthebalanceofweightsisnotjudgedcorrectly(
Fig.11.6
).
What?
Chapter|11
499
Furtherreading
David,E.,1977.EnglishBreadandYeastCookery.AllenLane,London,UK,pp.203

204.
FIGURE11.5
Cottageloafcutting.
FIGURE11.6
Incorrectdoughpieceweightsinthemanufactureofacottageloaf.
500
BakingProblemsSolved
:Pagenumbersfollowedby
and
refertofiguresandtables,respectively.
,158
-amylase,139
Bakerschocolate,418
Bakersyeast
fermentation,34,97,224
lagphase,127
precautionsinhandling,123
types,128
Bakeryfats,79
changesinbreaddoughduring,185
changesincakeduring,274
conditions,155,179,190,244,246,
280,288,292,317,364
370,373,384,473
Bakingpowder
correctproportionsofacidandalkali,130
insufficientinspongecake,288
levelandspongecake,286
287,287
Baladybread,435
Banburybiscuits,328
Barley,40,63,112,438
changesinpropertieswithtime,291
conversiontocakeintheoven,274
curdled,238
discolourationfromfruit,260
freezingcakebatters,246
glutenformationinwaferbatters,327
Bufferingagents,224
Bulkfermentation,53,58
60,120,127,178,
195,201,443,450
451,455
Buns,93
94,100,204,229,377
Butter,86
Buttercream,401
fishytaint,408
walnutsanddiscolouration,104
Buttermilk,422
Butyricacid,89
Cakedecorations,393
Cakes/cakemaking,235
batterdepositweightsanddifferentpan
sizes,279
,297
browninginfruitcakes,261,277
butterin,86
cakebattertemperatures
calculation,240
effectoncakequalityandvolume,239
cakeflourcharacteristics,71
cakemuffins,276,294
296,294
creamcakes,410
Cocoapowder,293
CodexAlimentariusCommissionoftheFood
andAgriculturalOrganisationofthe
UnitedNations,65
Co-extrudedpolypropylenefilm,489
Coffeemeringues,403
breaddoughs,81
cakes,67
chouxbuns,36
doughnuts,210
fruitedbuns,217
spongesandwiches,286
sultanacake,264
whippedcream,406
Seealso
Discolouration
crumb,259
crust,179
De-aeration,291
Deep-freezing,463
Seealso
frozenproducts
Deformationtesting,54
Dehydro-ascorbicacid(DHA),120,195
Flashheat,269
Flour,43
-amylase,58
ashcontent,43
functionsofdifferentcomponents,33
newharvesteffect,39
rationaleinmixingdifferentwheats,36
Glycerolmonostearate(GMS),86,105,141,
189,385,410
Goldensyrup,261
Gradecolourfigure,35,43,44
,45
46,231,
Grantwholemealloaf,440
Greasiness,indoughnuts,212
Groundalmonds,245
HagbergFallingNumber,57
58,61,63,114
Hamburgerbuns,pHandTTAofbrew,224
Handsqueezetest,475
Hearth-stylebreads,156
Heatbalance,173
174,173
Heatofhydration,68,241
Heattransferrate,210,279,289
Heat-treatedflour,68
Heat-treatedmilk,101
Heavilyfruitedcakes,249
Hemicellulases,114
Hemicellulose,114
Highfructosecornsyrup,95,97,311
High-ratiocakes,71
batterviscosity,266
cherrycake,471
breadrolls,213
incrumbofpanbreads,161
infruitedslabcake,263
Lignin,65
Lipase,304
Lipids,35,114
Lipoxygenase,138
Loafshape,234,278,499
Loafstylecakes,151
breakingononesideofthepan,198
externalappearance,196
internalappearance,197
stainsaroundfruitpieces,229
touchingloaf,205
206,205
Macaroons,404
Maillard-typereactions,179
Maltflour,40,112
Maltedgrains,40
Maltingprocess,40,112
Maltitol,495
Maltogenicamylases,139,190
Maltose,96,114,116,139,179,185,229
Oil,79
80,85,88
Oilabsorption,212
Oligosaccharides,486
Organicflours,75
Osmophilicyeasts,429
Osmoticpressure,97,204,497
Osmotolerance,204
conditionsandpeakinginspongecakes,288
variationsincakequality,269
Ovenbreak,198
Ovenlift,204
Ovenspring,133
lackof,81,216
Oven-bottombreads,156
Over-greasedtins,440
Oxidases,115
Oxidativerancidity,304
Oxidisingagents,133
134.
Seealso
Improvers
Oxygen,121
Palatecling,84,366
Palmoil,79
Panbread
airocclusion,165
holes,161
indentsinbases(pan-lock),153
largeholesincrumb,161
open-top,168
smoothsidedhole,164
strandedholes,163
mostcommonformsofassessment
crumbsoftness,105
moisturecontent,325,463
shape,288
biscuits,306
onfudgeicing,395
specklesofsodiumbicarbonate,
sugarspotsoncakecrusts,258
unbakedpuffpastry,341
Tristimulusinstruments,8
Tunnelholes,294,294
Twin-armtypemixer,459
UK-stylebloomers,48
Under-proveddoughs,156
Unsaturatedfats,77
Vacuumpump,170
Vacuum-coolingprinciples,467
Viennesefingers,329
Vinefruits,249.
Seealso
Fruitbreads;Fruit
cakes;Fruitedbuns
Vinegar,109.
Seealso

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