legume

legume, common name for any plant of the family Leguminosae, which is called also the pulse, legume, pea, or bean family. The word is often used loosely in the plural for vegetables in general. Botanically, a legume is the characteristic fruit of the pulse family plants, called also leguminous plants. It is a pod which usually splits along two sides, with the seeds attached along one of the sutures. The family Leguminosae is classified in the division Magnoliophyta, class Magnoliopsida, order Rosales.

Any of about 18,000 species in about 650 genera of flowering plants that make up the order Fabales, consisting of the single family Leguminosae, or Fabaceae (the pea family). The term also refers to their characteristic fruit, also called a pod. Legumes are widespread on all habitable continents. Leaves of many members appear feathery, and flowers are almost universally showy. In economic importance, this order is surpassed only by the grass and sedge order (Cyperales). In the production of food, the legume family is the most important of any family. The pods are part of the diet of nearly all humans and supply most dietary protein in regions of high population density. In addition, legumes perform the invaluable act of nitrogen fixation. Because they contain many of the essential amino acids, legume seeds can balance the deficiencies of cereal protein. Legumes also provide edible oils, gums, fibers, and raw material for plastics, and some are ornamentals. Included in this family are acacia, alfalfa, beans, broom, carob, clover, cowpea, lupine, mimosa, peas, peanuts, soybeans, tamarind, and vetch.

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Pulses are annual leguminous crops yielding from one to twelve grains or seeds of variable size, shape and color within a pod, according to the Food and Agricultural Organization of the United Nations (FAO). Pulses are used for food and animal feed.

The term pulses, as used by the FAO, is reserved for crops harvested solely for the dry grain. This excludes green beans and green peas, which are considered vegetable crops. Also excluded are crops that are mainly grown for oil extraction (oilseeds like soybeans and peanuts), and crops which are used exclusively for sowing (clovers, alfalfa).

Pulses are important food crops due to their high protein and essential amino acid content. Like many leguminous crops, pulses play a key role in crop rotation due to their ability to fix nitrogen.

World economy

India is the world's largest producer and the largest importer of pulses. Canada, Myanmar, Australia and the United States are significant exporters, and are India's most significant suppliers, in that order.

The vast majority of leguminous crops grown in the United States are soybeans, used as livestock feed and for extraction of vegetable oil, and peanuts, neither of which is considered a pulse.

Classification

FAO recognizes 11 primary pulses.

1. Dry beans (Phaseolus spp. including several species now in Vigna)
• Kidney bean, haricot bean, pinto bean, navy bean (Phaseolus vulgaris)
• Lima bean, butter bean (Vigna lunatus)
• Azuki bean, adzuki bean (Vigna angularis)
• Mung bean, golden gram, green gram (Vigna radiata)
• Black gram, Urad (Vigna mungo)
• Scarlet runner bean (Phaseolus coccineus)
• Rice bean (Vigna umbellata)
• Moth bean (Vigna acontifolia)
• Tepary bean (Phaseolus acutifolius)
2. Dry broad beans (Vicia faba)
• Horse bean (Vicia faba equina)
• Broad bean (Vicia faba)
• Field bean (Vicia faba)
3. Dry peas (Pisum spp.)
• Garden pea (Pisum sativum var. sativum)
• Protein pea (Pisum sativun var. arvense)
4. Chickpea, Garbanzo, Bengal gram (Cicer arietinum)
5. Dry cowpea, Black-eyed pea, blackeye bean (Vigna unguiculata )
6. Pigeon pea, Toor, cajan pea, congo bean (Cajanus cajan)
7. Lentil (Lens culinaris)
8. Bambara groundnut, earth pea (Vigna subterranea)
9. Vetch, common vetch (Vicia sativa)
10. Lupins (Lupinus spp.)
11. Minor pulses include:
• Lablab, hyacinth bean (Lablab purpureus)
• Jack bean (Canavalia ensiformis), sword bean (Canavalia gladiata)
• Winged bean (Psophocarpus teragonolobus)
• Velvet bean, cowitch (Mucuna pruriens var. utilis)
• Yam bean (Pachyrrizus erosus)

Protein content

Pulses are 20 to 25% protein by weight, which is double the protein content of wheat and three times that of rice. For this reason, pulses are sometimes called "poor man’s meat". While pulses are generally high in protein, and the digestibility of that protein is also high, they often are relatively poor in the essential amino acid methionine. Grains (which are themselves deficient in lysine) are commonly consumed along with pulses to form a complete protein diet.

Health

Pulses have significant nutritional and health advantages for consumers. They are the most important dietary predictor of survival in older people of different ethnicities, and in the Seven Countries Study, legume consumption was highly correlated with a reduced mortality from coronary heart disease.

References

• Food and Agriculture Organization. DEFINITION AND CLASSIFICATION OF COMMODITIES, 4. PULSES AND DERIVED PRODUCTS, 1994

See also

Bean Common bean

Legume Fabaceae

External links

• http://www.pulsecanada.com/
• http://www.specialcrops.mb.ca/
• http://www.grainlegumes.com/
• http://www.beanslentils.com/about_b&l.htm