On food and cooking the science and lore of the kitchen ( PDFDrive ) 1131
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10%ormore,tohaverealweight.Butatthat
concentration,thesauceisquicktocongealon
acoolingplate,anditcanalsocausetheteeth
tosticktogether(gelatinmakesanexcellent
glue!).
Gelatin Comes from Collagen Free gelatin
molecules don’t exist in meat and fish.
They’re woven tightly together to form the
fibrous connective-tissue protein called
collagen (p. 130), which gives mechanical
strengthtomuscles,tendons,skin,andbones.
Singlegelatinmoleculesarechainsofaround
1,000 amino acids. Thanks to the repeating
pattern of their amino acids, three gelatin
molecules naturally fit alongside each other
and form weak, reversible bonds that arrange
the three molecules in the form of a triple
helix.Manytriplehelixesthenbecomecrosslinkedtoeachothertoformthestrong,ropelikefibersofcollagen.
Cooksgenerategelatinfromcollagenby
usingheattodismantlethecollagenfibers.
Forthemusclesoflandanimals,ittakesa
temperatureofaround140ºF/60ºCtoagitate
themusclemoleculesenoughtobreakthe
weakbondsofthetriplehelix.Theorderly
structureofthecollagenfibersthencollapses
andthefibersshrink,thussqueezingjuices
fromthemusclefibers.Someofthejuices
bathethefibers,andsinglegelatinmolecules
orsmallaggregatesmaydisperseintothe
juice.Thehigherthemeattemperaturegoes,
themoregelatinbecomesdispersed.However,
manyofthecollagenfibersremainintact
thankstothestrongcross-linkingbonds.The
oldertheanimalandthemoreworkits
musclesdo,themorestronglycross-linkedits
collagenfibersare.
ExtractingGelatin
andFlavorfromMeats
Themusclesthatmakeupmeataremainly
