On food and cooking the science and lore of the kitchen ( PDFDrive ) 1142
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cookingliquidofpoachedorsteamedfish,
sinceevenbriefcookingwillextractflavor
andgelatinintotheliquid.Thetraditional
cookingliquidforfishisacourtbouillonor
“quickbouillon”madebybrieflycooking
water,salt,wine,andaromaticstogether(p.
215).
Thebonyshellsofcrustaceansdon’t
containcollagen,socookingtheminwater
won’tgivebodytotheextract.Infact
crustaceanshellsarenormallyextractedin
butteroroil,sincetheirpigmentsandflavors
aremoresolubleinfatthaninwater(p.220).
OtherProteinThickeners
Gelatinistheeasiest,mostforgivingprotein
anycookdealswith.Heatitupwithwaterand
itsmoleculesletgoofeachotherandbecome
dispersedamongthewatermolecules;coolit
andtheyrebondtoeachother;heatitagain
andtheydisperseagain.Nearlyallother
proteinsinanimalsandplantsbehavein
exactlytheoppositeway:heatcausesthemto
unfoldfromtheirnormallycompactshape,
becomeentangled,andformstrongbonds
witheachother,sothattheycoagulate
permanentlyandirreversiblyintoafirmsolid.
Thusliquideggssolidify,pliablemuscle
tissuebecomesstiffmeat,andmilkcurdles.
Ofcourseasolidpieceofcoagulatedprotein
can’tbeasauce.Butit’spossibletocontrol
proteincoagulationsothatitcangivebodyto
sauces.
Proteinthickeningandcurdling.Twopossible
outcomesofheatingeggproteins,whichstart
out folded in compact shapes (left).If
conditions favor their unfolding, they form a
loose network of long chains (center)and
