On food and cooking the science and lore of the kitchen ( PDFDrive ) 1019
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theybeginfermentation,buttherisingofthe
doughcontinuestodevelopglutenstructure
(below),solittle-kneadeddoughscan
eventuallyrisewelltogiveanairy,tender
crumb.
Fermentation,orRising
Fermentationisthestageduringwhichthe
doughissetasidefortheyeastcellsto
producecarbondioxide,whichdiffusesinto
theairpockets,slowlyinflatesthem,andthus
raisesthedough.Thisgentlestretchingaction
continuestheprocessofglutenorientation
anddevelopment,asdoestheoxidizingeffect
ofotheryeastby-products,whichcontinueto
helpthegluteninmoleculestolinkupend-toend.Asaresult,eveninitiallywet,barely
cohesivedoughsbecomemoremanageable
afterfermentation.
Yeastsproducecarbondioxidemost
rapidlyataround95ºF/35ºC,buttheyalso
producemorenoticeablequantitiesofsour
andunpleasant-smellingby-products.A
fermentationtemperatureof80ºF/27ºCis
oftensuggestedforarelativelyquickrising
timeofacoupleofhours.Lowertemperatures
mayextendfermentationtimesbyanhouror
more,andwiththemthegenerationof
desirableyeastflavors.
Theendofthefermentationperiodis
signaledbythedough’svolume—it
approximatelydoubles—andbythe
conditionoftheglutenmatrix.Whenpoked
withthefinger,fullyfermenteddoughwill
retaintheimpressionandwon’tspringback:
theglutenhasbeenstretchedtothelimitofits
elasticity.Thedoughisnowgentlyhandledto
reconsolidatethegluten,dividethegas
pockets,redistributetheyeastcellsandtheir
foodsupply,andevenoutthetemperatureand
moisture(fermentationgeneratesheat,water,
andalcohol).Thankstotheaddedmoisture
andtothegluten-interruptingbubbles,
