Tomato is the common name for a perennial herb, Lycopersicon esculentum, of the nightshade family, Solanaceae, and for its edible fruit. Like the potato and the green pepper, to which it is closely related, the tomato originated in Central America. Spanish explorers introduced tomato seeds into Europe and North America, but the "love apple" did not become popular in either area until the 19th century.
Botanically the tomato is a fruit, but for purposes of trade it is classified as a vegetable. Because tomatoes are warm-season plants and sensitive to frosts, they are grown as annuals in temperate climates. Rich in potassium and vitamins A and C, varieties range in size from 2 cm (less than 1 in) in diameter to over 15 cm (6 in); in color from white to yellow to orange to deep red; in shape from ovals to oblongs to teardrops; and in flavor from highly acidic to very sweet. They are cultivated commercially in every U.S. state except Alaska.
Tomatoes are the most widely used canned vegetable in the United States. About 75 percent of the total tomato crop is processed into juice, canned tomatoes, sauces, pastes, and ketchup. California, Florida, Michigan, and Ohio are the major U.S. tomato-growing states. Mexico and Israel supply much of the winter crop of fresh produce for U.S. markets.
Tomatoes that are machine-harvested green and chemically ripened have very little taste compared to vine-ripened fruit. In 1992 bioengineers perfected a gene-altered tomato that can be picked ripe and stays firm on the shelf. In 1994, the U.S. Food and Drug Administration judged this tomato "as safe as tomatoes bred by conventional means," thus releasing it for commercial sale.
O. A. Lorenz
Bibliography: Gould, W., Tomato Production, Processing and Quality Evaluation, 2d ed. (1983; repr. 1992); Kalloo, G., et al., eds., Genetic Improvement of the Tomato (1991).