The tomato is the edible, often red fruit/berry of the plant Solanum lycopersicum, commonly known as a tomato plant. The species originated in the South American Andes 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 tomato is consumed in diverse ways, including raw, as an ingredient in many dishes, sauces, salads, and drinks. While it is botanically a fruit, it is considered a vegetable for culinary purposes (as well as under U.S. customs regulations, see Nix v. Hedden), which has caused some confusion. The fruit is rich in lycopene, which may have beneficial health effects.
The tomato belongs to the nightshade family (Solanaceae). 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
Aztecs and other peoples in Mesoamerica used the fruit in their cooking. The exact date of domestication is unknown: by 500 BC, it was already being cultivated in southern Mexico and probably other areas.:13 The Pueblo people are thought to have believed that those who witnessed the ingestion of tomato seeds were blessed with powers of divination. The large, lumpy tomato, a mutation from a smoother, smaller fruit, originated in Mesoamerica, and may be the direct ancestor of some modern cultivated tomatoes.
Spanish conquistador Hernán Cortés may have been the first to transfer the small yellow tomato to Europe after he captured the Aztec city of Tenochtítlan, now Mexico City, in 1521, although Christopher Columbus, a Genoese working for the Spanish monarchy, may have taken them back as early as 1493. The earliest discussion of the tomato in European literature appeared in an herbal written in 1544 by Pietro Andrea Mattioli, an Italian physician and botanist, who suggested that a new type of eggplant had been brought to Italy that was blood red or golden color when mature and could be divided into segments and eaten like an eggplant—that is, cooked and seasoned with salt, black pepper, and oil. However it wasn't until ten years later that tomatoes were named in print by Mattioli as pomi d’oro, or "golden apple".:13
After the Spanish colonization of the Americas, the Spanish distributed the tomato throughout their colonies in the Caribbean. They also took it to the Philippines, from where it spread to southeast Asia and then the entire Asian continent. The Spanish also brought the tomato to Europe. It grew easily in Mediterranean climates, and cultivation began in the 1540s. It was probably eaten shortly after it was introduced, and was certainly being used as food by the early 17th century in Spain. The earliest discovered cookbook with tomato recipes was published in Naples in 1692, though the author had apparently obtained these recipes from Spanish sources.:17 In certain areas of Italy, such as Florence, however, the fruit was used solely as a tabletop decoration before it was incorporated into the local cuisine in the late 17th or early 18th century.
The recorded history of tomatoes in Italy dates back to 31 October 1548 when the house steward of Cosimo de' Medici, the grand duke of Tuscany, wrote to the Medici private secretary informing him that the basket of tomatoes sent from the grand duke's Florentine estate at Torre del Gallo "had arrived safely." Tomatoes were grown mainly as ornamentals early on after their arrival in Italy. For example, the Florentine aristocrat Giovanvettorio Soderini wrote how they "were to be sought only for their beauty" and were grown only in gardens or flower beds. The tomato's ability to mutate and create new and different varieties helped contribute to its success and spread throughout Italy. However, even in areas where the climate supported growing tomatoes, their proximity of growing to the ground suggested low status. They were not adopted as a staple of the peasant population because they were not as filling as other fruits already available. Additionally, both toxic and inedible varieties discouraged many people from attempting to consume or prepare them.
Unique varieties were developed over the next several hundred years for uses such as dried tomatoes, sauce tomatoes, pizza tomatoes, and tomatoes for long term storage. These varieties are usually known for their place of origin as much as by a variety name. For example, Pomodorino del Piennolo del Vesuvio is the "hanging tomato of Vesuvius". Five different varieties have traditionally been used to make these "hanging" tomatoes. They are Fiaschella, Lampadina, Patanara, Principe Borghese, and Re Umberto. Other tomatoes that originated in Italy include San Marzano, Borgo Cellano, Christopher Columbus, Costoluto Genovese, and Italian Pear. These tomatoes are characterized by relatively intense flavor compared to varieties typically grown elsewhere.
Tomatoes were not grown in England until the 1590s.:17 One of the earliest cultivators was John Gerard, a barber-surgeon.:17 Gerard's Herbal, published in 1597, and largely plagiarized from continental sources,:17 is also one of the earliest discussions of the tomato in England. Gerard knew the tomato was eaten in Spain and Italy.:17 Nonetheless, he believed it was poisonous:17 (in fact, the plant and raw fruit do have low levels of tomatine, but are not generally dangerous; see below). Gerard's views were influential, and the tomato was considered unfit for eating (though not necessarily poisonous) for many years in Britain and its North American colonies.:17 By the mid-18th century, tomatoes were widely eaten in Britain, and before the end of that century, the Encyclopædia Britannica stated the tomato was "in daily use" in soups, broths, and as a garnish. They were not part of the average man's diet, however, and though by 1820 they were described as "to be seen in great abundance in all our vegetable markets" and to be "used by all our best cooks", reference was made to their cultivation in gardens still "for the singularity of their appearance", while their use in cooking was associated with Italian or Jewish cuisine.
Middle East and North Africa
The tomato was introduced to cultivation in the Middle East by John Barker, British consul in Aleppo circa 1799 to 1825. Nineteenth century descriptions of its consumption are uniformly as an ingredient in a cooked dish. In 1881, it is described as only eaten in the region "within the last forty years". Today, the tomato is a critical and ubiquitous part of Middle Eastern cuisine, served fresh in salads (e.g. Arab salad, Israeli salad, and Turkish salad), grilled with kebabs and other dishes, made into sauces, and so on.
The early name used for tomato in Iran was Armani badenjan (Armenian eggplant). Currently, the name used for tomato in Iran is gojeh farangi [French plum].
The earliest reference to tomatoes being grown in British North America is from 1710, when herbalist William Salmon reported seeing them in what is today South Carolina.:25 They may have been introduced from the Caribbean. By the mid-18th century, they were cultivated on some Carolina plantations, and probably in other parts of the Southeast as well. Possibly, some people continued to think tomatoes were poisonous at this time; and in general, they were grown more as ornamental plants than as food. Thomas Jefferson, who ate tomatoes in Paris, sent some seeds back to America.:28
Alexander W. Livingston was the first person who succeeded in upgrading the wild tomato, developing different breeds and stabilizing the plants. In the 1937 yearbook of the Federal Department of Agriculture, it was declared that "half of the major varieties were a result of the abilities of the Livingstons to evaluate and perpetuate superior material in the tomato". Livingston's first breed of tomato, the Paragon, was introduced in 1870. In 1875, he introduced the Acme, which was said to be involved in the parentage of most of the tomatoes introduced by him and his competitors for the next twenty-five years.
When Alexander W. Livingston had begun his attempts to develop the tomato as a commercial crop, his aim had been to grow tomatoes smooth in contour, uniform in size and having better flavor. One year, after many attempts, he passed through his fields, picking out particular tomato plants having distinct characteristics and heavy foliage. He saved the seeds carefully. The following spring he set two rows across his family garden located just below the hill and milk house. To his happy surprise, each plant bore perfect tomatoes like the parent vine. After five years, the fruit became fleshier and larger. In 1870, Alexander introduced the Paragon and tomato culture soon became a great enterprise in the county. Today, the crop is grown in every state in the Union. He eventually developed over seventeen different varieties of the tomato plant.
Because of the long growing season needed for this heat-loving crop, several states in the US Sun Belt became major tomato-producers, particularly Florida and California. In California, tomatoes are grown under irrigation for both the fresh fruit market and for canning and processing. The University of California, Davis (UC Davis) became a major center for research on the tomato. The C.M. Rick Tomato Genetics Resource Center at UC Davis is a gene bank of wild relatives, monogenic mutants and miscellaneous genetic stocks of tomato. The Center is named for the late Dr. Charles M. Rick, a pioneer in tomato genetics research. Research on processing tomatoes is also conducted by the California Tomato Research Institute in Escalon, California.
In California, growers have used a method of cultivation called dry-farming, especially with Early Girl tomatoes. This technique encourages the plant to send roots deep to find existing moisture in soil that retains moisture, such as clayey soil.
Modern commercial varieties
The poor taste and lack of sugar in modern garden and commercial tomato varieties resulted from breeding tomatoes to ripen uniformly red. This change occurred after discovery of a variety in the mid 20th century that ripened uniformly. This was widely cross-bred to produce red fruit without the typical green ring around the stem on uncross-bred varieties. Prior to general introduction of this trait, most tomatoes produced more sugar during ripening, and were sweeter and more flavorful.
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 150 million tons of tomatoes were produced in the world in 2009. China, the largest producer, accounted for about one quarter of the global output, followed by United States and India. For one variety, plum or processing tomatoes, California accounts for 90% of U.S. production and 35% of world production.
Within the EU, there are several areas that grow tomatoes with Protected Geographical Status. These include:
There are around 7500 tomato varieties grown for various purposes. Heirloom tomatoes are becoming increasingly popular, particularly among home gardeners and organic producers, since they tend to produce more interesting and flavorful crops at the cost of disease resistance and productivity. In 1973, Israeli scientists developed the world's first long shelf-life commercial tomato varieties.
Hybrid plants remain common, since they tend to be heavier producers, and sometimes combine unusual characteristics of heirloom tomatoes with the ruggedness of conventional commercial tomatoes.
Tomato varieties are roughly divided into several categories, based mostly on shape and size.
- "Slicing" or "globe" tomatoes are the usual tomatoes of commerce, used for a wide variety of processing and fresh eating.
- Beefsteak tomatoes are large tomatoes often used for sandwiches and similar applications. Their kidney-bean shape, thinner skin, and shorter shelf life makes commercial use impractical.
- Oxheart tomatoes can range in size up to beefsteaks, and are shaped like large strawberries.
- Plum tomatoes, or paste tomatoes (including pear tomatoes), are bred with a higher solids content for use in tomato sauce and paste, and are usually oblong.
- Pear tomatoes are pear-shaped, and are based upon the San Marzano types for a richer gourmet paste.
- Cherry tomatoes are small and round, often sweet tomatoes generally eaten whole in salads.
- Grape tomatoes, a more recent introduction, are smaller and oblong, a variation on plum tomatoes, and used in salads.
- Campari tomatoes are also sweet and noted for their juiciness, low acidity, and lack of mealiness. They are bigger than cherry tomatoes, but are smaller than plum tomatoes.
Early tomatoes and cool-summer tomatoes bear fruit even where nights are cool, which usually discourages fruit set. There are also varieties high in beta carotenes and vitamin A, hollow tomatoes and tomatoes that keep for months in storage.
Tomatoes are also commonly classified as determinate or indeterminate. Determinate, or bush, types bear a full crop all at once and top off at a specific height; they are often good choices for container growing. Determinate types are preferred by commercial growers who wish to harvest a whole field at one time, or home growers interested in canning. Indeterminate varieties develop into vines that never top off and continue producing until killed by frost. They are preferred by home growers and local-market farmers who want ripe fruit throughout the season. As an intermediate form, there are plants sometimes known as vigorous determinate or semideterminate; these top off like determinates, but produce a second crop after the initial crop. The majority of heirloom tomatoes are indeterminate, although some determinate heirlooms exist.
Most modern tomato cultivars are smooth surfaced, but some older tomato cultivars and most modern beefsteaks often show pronounced ribbing, a feature that may have been common to virtually all pre-Columbian cultivars. While virtually all commercial tomato varieties are red, some cultivars – especially heirlooms – produce fruit in other colors, including green, yellow, orange, pink, black, brown, ivory, white, and purple. Such fruits are not widely available in grocery stores, nor are their seedlings available in typical nurseries, but they can be bought as seed. Less common variations include fruit with stripes (Green Zebra), fuzzy skin on the fruit (Fuzzy Peach, Red Boar), multiple colors (Hillbilly, Burracker's Favorite, Lucky Cross), etc.
There is also a considerable gap between commercial and home-gardener cultivars. Home cultivars are often bred for flavor to the exclusion of all other qualities, while commercial cultivars are bred for factors like consistent size and shape, disease and pest resistance, suitability for mechanized picking and shipping, and ability to ripen after picking.
Tomatoes grow well with seven hours of sunlight a day. A fertilizer with an NPK ratio of 5-10-10 is often sold as tomato fertilizer or vegetable fertilizer, although manure and compost are also used.
Various heirloom tomato cultivars