On food and cooking the science and lore of the kitchen ( PDFDrive ) 1520

Protein Coagulation There are several
general consequences of denaturation that
follow for most food proteins. Because the
molecules have been extended in length,
they’re more likely to bump into each other.
And because their side groups are now
exposed and available for forming bonds,
denatured proteins begin to bond with each
other, orcoagulate. This happens throughout
the food, and results in the development of a
continuous network of proteins, with water
held in the pockets between protein strands.
The food therefore develops a kind of
thickness or density that can be delicate and
delightful, as in a barely set custard or
perfectly cooked piece of fish. However, if
cooking or other denaturing conditions
continue, given the extreme physical or
chemicalenvironmentthatcausedtheproteins
todenatureinthefirstplace,onlythestronger
bondscanformandsurvive,whichmeansthat
the proteins bond together more and more


tightly,densely,andirreversibly.Andasthey
do so, they squeeze the pockets of water out
from between them. The custard gets dense
and a watery fluid separates from the solid
portion;thefishgetstoughanddry.
Thedetailsofproteindenaturationand
coagulationinanygivenfoodareintricateand

fascinating.Forexample,acidityandsaltscan
causeeggproteinstoclustertogethereven
beforetheybegintounfold,andthusaffect
theconsistencyofscrambledeggsand
custards.Suchdetailsarenotedinthe
descriptionsofparticularfoods.
Enzymes

There’saparticulargroupofproteinsthatare
importanttothecooknotsomuchfortheir
directcontributiontofoodtextureand
consistency,butforthewaytheychangethe
othercomponentsofthefoodthey’rein.
Theseproteinsaretheenzymes.Enzymesare