On food and cooking the science and lore of the kitchen ( PDFDrive ) 552
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uncontrolledenzymeactivity,andexposureto
oxygen and to light. They and minerals can
alsobedrawnoutofplanttissuesbycooking
water.Theselossescanbeminimizedbyrapid
and brief cooking. Baked potatoes, for
example, heat up relatively slowly and lose
much more vitamin C to enzyme action than
doboiledpotatoes.However,sometechniques
that speed cooking — cutting vegetables into
smallpieces,andboilinginalargevolumeof
water,whichmaintainsitstemperature—can
result in increased leaching of water-soluble
nutrients,includingmineralsandtheBandC
vitamins. To maximize the retention of
vitaminsandminerals,cooksmallbatchesof
vegetables and fruits in the microwave oven,
inaminimalamountofaddedwater.
…And Some Enhancement Cooking has
several general nutritional benefits. It
eliminates potentially harmful microbes. By
softening and concentrating foods, it also
makes them easier to eat in significant
quantities. And it actually improves the
availability of some nutrients. Two of the
most important are starch and the carotenoid
pigments. Starch consists of long chains of
sugar molecules crammed into masses called
granules. Our digestive enzymes can’t
penetrate past the outer layer of raw starch
granules, but cooking unpacks the starch
chainsandletsourenzymesbreakthemdown.
Thentherearebeta-carotene,theprecursorto
vitaminA, its chemical relative lycopene, an
important antioxidant, and other valuable
carotenoidpigments.Becausethey’renotvery
soluble in water, we simply don’t extract
these chemicals very efficiently by just
chewingandswallowing.Cookingdisruptsthe
planttissuesmorethoroughlyandallowsusto
extract much more of them. (Added fat also
significantly improves our absorption of fatsolublenutrients.)
