On food and cooking the science and lore of the kitchen ( PDFDrive ) 586
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brown too rapidly and develop a bitter taste.
Internalblackspotsinpotatoesareessentially
bruises, formed when an impact during
handling damages cells and causes the
browning enzymes to create dark complexes
oftheaminoacidtyrosine(alkaloidformation
andthereforebitternessoftenrisealso).
Nutritional Qualities Potatoes are a good
source of energy and vitamin C. Yellowfleshedvarietiesowetheircolortofat-soluble
carotenoids (lutein, zeaxanthin), purple and
blue ones to water-soluble and antioxidant
anthocyanins. Potatoes are notable for
containing significant levels of the toxic
alkaloids solanine and chaconine, a hint of
whose bitterness is part of their true flavor.
Most commercial varieties contain 2 to 15
milligrams of solanine and chaconine per
quarter-pound (100 grams) of potato.
Progressively higher levels result in a
distinctly bitter taste, a burning sensation in
the throat, digestive and neurological
problems, and even death. Stressful growing
conditionsandexposuretolightcandoubleor
triple the normal levels. Because light also
induceschlorophyllformation,agreencastto
the surface is a sign of abnormally high
alkaloid levels. Greened potatoes should
either be peeled deeply or discarded, and
stronglybitterpotatoesshouldnotbeeaten.
Cooking Types and Behavior There are two
general cooking categories of potato, called
the“mealy”andthe“waxy”fortheirtextures
when cooked. Mealy types (russets, blue and
purple varieties, Russian and banana
fingerlings) concentrate more dry starch in
theircells,sothey’redenserthanwaxytypes.
When cooked, the cells tend to swell and
separate from each other, producing a fine,
dry, fluffy texture that works well in fried
potatoes and in baked and mashed potatoes,
whicharemoistenedwithbutterorcream.In
