On food and cooking the science and lore of the kitchen ( PDFDrive ) 871
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tissue,anditsmakeupdeterminestheseed’s
basictexture.Thestoragecellsarefilledwith
particlesofconcentratedprotein,granulesof
starch,andsometimeswithdropletsofoil.In
somegrains,notablybarley,oats,andrye,the
cellwallsarealsofilledwithstorage
carbohydrates—notstarch,butotherlong
sugarchainsthatlikestarchcanabsorbwater
duringcooking.Thestrengthofthecement
thatholdsthestoragecellstogether,andthe
natureandproportionsofthematerialsthey
contain,determinetheseed’stexture.Bean
cellsandgraincellsarefilledwithsolid,hard
starchgranulesandproteinbodies;mostnut
cellsarefilledwithliquidoil,andsoaremore
fragile.Grainsretaintheirshapeandsome
firmnessevenwhenwemillawaytheir
protectivebranenvelopeandboilthemin
plentyofwater.Beansremainintactaslong
aswecookthemintheirseedcoats;otherwise
theyrapidlydisintegrateintoapuree.
Theparticularcontentsoftheseedstorage
cellsinfluencetextureandculinaryusefulness
inanumberofways.Soit’sworthknowing
abouttheproteins,starches,andoilsinsome
detail.
SeedProteins:SolubleandInsoluble
Seedproteinsareclassifiedbyaparticular
aspectoftheirchemicalbehavior,whichalso
determinestheirbehaviorduringcooking:the
kindofliquidinwhichtheydissolve.This
maybepurewater,waterandsomesalt,water
anddiluteacid,oralcohol(thesetypesare
called“albumins,”“globulins,”“glutelins,”
and“prolamins”).Mostoftheproteinsin
legumesandnutsaresolubleinasaltsolution
orwateralone,soduringordinarycookingin
saltedwater,beanandpeaproteinsbecome
dispersedinthemoisturewithintheseedsand
thecookingliquidsurroundingthem.By
contrast,themainstorageproteinsinwheat,
rice,andothergrainsareacid-solubleand
