The tomato (see pronunciation) is the edible, often red berry-type fruit of the nightshade Solanum lycopersicum, commonly known as a tomato plant. The tomato is consumed in diverse ways, including raw, as an ingredient in many dishes, sauces, salads, and drinks. The English word tomato comes from the Spanish word, tomate, derived from the Nahuatl (Aztec language) word tomatl. It first appeared in print in 1595.
The tomato belongs to the nightshade family, Solanaceae. The species originated in Central and South America and its use as a food originated in Mexico, and spread throughout the world following the Spanish colonization of the Americas. Its many varieties are now widely grown, sometimes in greenhouses in cooler climates. The plants typically grow to 1–3 meters (3–10 ft) in height and have a weak stem that often sprawls over the ground and vines over other plants. It is a perennial in its native habitat, although often grown outdoors in temperate climates as an annual. An average common tomato weighs approximately 100 grams (4 oz).
While tomatoes are botanically and scientifically the berry-type fruits of the tomato plant, they can also be considered a culinary vegetable, causing some confusion.
The tomato is now grown worldwide for its edible fruits, with thousands of cultivars having been selected with varying fruit types, and for optimum growth in differing growing conditions. Cultivated tomatoes vary in size, from tomberries, about 5 mm in diameter, through cherry tomatoes, about the same 1–2 cm (0.4–0.8 in) size as the wild tomato, up to beefsteak tomatoes 10 cm (4 in) or more in diameter. The most widely grown commercial tomatoes tend to be in the 5–6 cm (2.0–2.4 in) diameter range. Most cultivars produce red fruit, but a number of cultivars with yellow, orange, pink, purple, green, black, or white fruit are also available. Multicolored and striped fruit can also be quite striking. Tomatoes grown for canning and sauces are often elongated, 7–9 cm (3–4 in) long and 4–5 cm (1.6–2.0 in) diameter; they are known as plum tomatoes, and have a lower water content. Roma-type tomatoes are important cultivars in the Sacramento Valley.
Tomatoes are one of the most common garden fruits in the United States and, along with zucchini, have a reputation for outproducing the needs of the grower.
Quite a few seed merchants and banks provide a large selection of heirloom seeds. The definition of an heirloom tomato is vague, but unlike commercial hybrids, all are self-pollinators that have bred true for 40 years or more.
About 161.8 million tonnes of tomatoes were produced in the world in 2012. China, the largest producer, accounted for about one quarter of the global output, followed by India and the United States. For one variety, plum or processing tomatoes, California accounts for 90% of U.S. production and 35% of world production.
In 2012, tomato production was valued at 58 billion dollars and tomatoes were the eighth most valuable agricultural product worldwide.
Tomato products are heat processed tomato products including canned tomatoes (diced, whole peel, stewed), tomato sauce, tomato paste, tomato soup, tomato juice, and ketchup.
Important nutrients
Tomato products are a good source of vitamins C, A and K; potassium, magnesium and fiber. They are also low in calories; a 100-gram serving of canned tomatoes contains only 32 calories. Tomatoes are also high in the carotenoids, beta-carotene and lycopene.
Lycopene
Lycopene is a bright red carotene and carotenoid pigment found in tomatoes. There is no good evidence it has any health effect.
Cancer
Some studies have indicated that the lycopene in tomatoes may help prevent cancer, but taken overall the research into this subject is inconclusive.
Tomato products and heart health
Tomatoes contain nutrients that may work in concert to protect lipoproteins and vascular cells from oxidation, the most widely accepted theory for the genesis of atherosclerosis, according to researchers form the Department of Food Science at North Carolina State University. Other heart-protective activities in tomatoes may include the reduction of “bad” LDL cholesterol, homocysteine, platelet aggregation, and blood pressure.
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