On food and cooking the science and lore of the kitchen ( PDFDrive ) 551
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molecules by causing increased enzyme
activity, mixing of cell contents, and general
chemical reactivity. The more prolonged or
intense the heating, the more the food’s
original aroma molecules are modified and
supplemented, and so the more complex and
“cooked” the flavor. If the cooking
temperature exceeds the boiling point — in
frying and baking, for example — then these
carbohydrate-rich materials will begin to
undergo browning reactions, which produce
characteristicroastedandcaramelizedflavors.
Cookscancreateseverallayersofflavorina
dish by combining well-cooked, lightly
cooked, and even raw batches of the same
vegetablesorherbs.
Onesensoryqualityuniquetoplantsis
astringency(p.271),anditcanmakesuch
foodsasartichokes,unripefruits,andnuts
lessthanentirelypleasanttoeat.Thereare
waystocontroltheinfluenceoftanninsin
thesefoods.Acidsandsaltincreasethe
perceptionofastringency,whilesugarreduces
it.Addingmilk,gelatin,orotherproteinstoa
dishwillreduceitsastringencybyinducing
thetanninstobindtofoodproteinsbefore
theycanaffectsalivaryproteins.Ingredients
richinpectinorgumswillalsotakesome
tanninsoutofcirculation,andfatsandoils
willslowtheinitialbindingoftanninsand
proteins.
Nutritional Value Cooking destroys some of
the nutrients in food, but makes many
nutrients more easily absorbed. It’s a good
ideatoincludebothrawandcookedfruitsand
vegetablesinourdailydiet.
Some Diminishment of Nutritional Value…
Cooking generally reduces the nutritional
content of fruits and vegetables. There are
someimportantexceptionstothisrule,butthe
levels of most vitamins, antioxidants, and
otherbeneficialsubstancesarediminishedby
the combination of high temperatures,
