Maize plants range from 2 to 20 feet in height, with 8 to 48 leaves, 1 to 15 stalks from a single seed, and ears that range from thumb-sized (popcorn) to 2 feet in length. The different varieties have different geographical, climatic, and pest tolerances. The mature kernel consists of the pericarp (thin shell), endosperm (storage organ), and embryo or germ, which contains most of the fat, vitamins, and minerals and varies in chemical composition, shape, and color.
The principal maize classifications are based on grain starch and appearance - these characteristics influence suitability for end uses. In “flints,” the starch is hard. In “dents,” the kernel is softer, with a larger proportion of floury endosperm and hard starch confined to the side of the kernel. “Floury” varieties have soft and mealy starch;“pop” corns are very hard. “Sweet” corns have more sugar, and “waxy” maizes contain starch composed entirely of amylopectin, without the 22 percent amylose characteristic of dents.
Dents account for 95 percent of all maize. The kernels acquire the characteristic “dent” when the grain is dried and the soft, starchy amylose of the core and the cap contract. Most dent maize is yellow and is fed to livestock; white dents are preferred for human food in Mexico, Central. America, the Caribbean, and southern Africa. Flint maize, with its hard outer layer of starch, makes a very good-quality maize meal when dry-milled. It stores more durably than other types because it absorbs less moisture and is more resistant to fungi and insects. Flints germinate better in colder, wetter soils, mature earlier, and tend to perform well at higher latitudes. Popcorns are extremely hard flint varieties; when heated, the water in the starch steam-pressures the endosperm to explode, and the small kernels swell and burst.
Sweet corns are varieties bred especially for consumption in an immature state. A number of varieties of sweet corn, exhibiting simple mutations, were developed as garden vegetables in the United States beginning around 1800. Sweet varieties known as sara chulpi were known much earlier in the. Andes, where they were usually parched before eating. Floury maizes are grown in the Andean highlands of South America, where they have been selected for beer making and special food preparations (kancha), and in the U. S. Southwest, where they are preferred for their soft starch, which grinds easily. Waxy varieties are grown for particular dishes in parts of Asia and for use in industrial starches in the United States.
In addition, maize grains are classified by color, which comes mostly from the endosperm but is also influenced by pigments in the outer aleurone cell layer and pericarp. Throughout most of the world, white maize is preferred for human consumption and yellow for animal feed, although Central and Mediterranean Europeans eat yellow maize and indigenous Americans carefully select blue (purple, black), red, and speckled varieties for special regional culinary or ritual uses. Color is probably the most important classification criterion among New World indigenous cultivators, who use color terms to code information on the ecological tolerances, textures, and cooking characteristics of local varieties.
World History
