Common bean

From Wikipedia, the free encyclopedia

"Navy Bean" redirects here. For the song by Tracy Bonham, see The Burdens of Being Upright.

The common bean, Phaseolus vulgaris, indigenous to the Americas, is an herbaceous annual plant domesticated independently in ancient Mesoamerica and the Andes, and now grown worldwide for its edible bean, popular both dry and as a green bean. The leaf is occasionally used as a leaf vegetable, and the straw is used for fodder. Botanically, the common bean is classified as a dicotyledon. Beans, squash and maize comprised the "Three sisters" that provided the foundation of Native American agriculture. As a legume, beans provided the nitrogen fixing bacteria which supplied that essential nutrient to the other two crops.

Description

The common bean is a highly variable species. Bush varieties form erect bushes 20–60 cm tall, while pole or running varieties form vines 2–3 m long. All varieties bear alternate, green or purple leaves, divided into three oval, smooth-edged leaflets, each 6–15 cm long and 3–11 cm wide. The white, pink, or purple flowers are about 1 cm long, and give way to pods 8–20 cm long, 1–1.5 cm wide, green, yellow, black or purple in color, each containing 4–6 beans. The beans are smooth, plump, kidney-shaped, up to 1.5 cm long, range widely in color, and are often mottled in two or more colors.

As the common bean is a dicot, it germinates as such:

• The primary root emerges through the seed coats while the seed is still buried in the soil.
• The hypocotyl emerges from the seed coats and pushes its way up through the soil. It is bent in a hairpin shape — the hypocotyl arch (Crozier's hook) — as it grows up. The two cotyledons protect the epicotyl structures — the plumule — from mechanical damage.
• Once the hypocotyl arch emerges from the soil, it straightens out. This response is triggered by light (phototropism). Both red light, absorbed by phytochrome and blue light, absorbed by cryptochrome can do the job.
• The cotyledons spread apart, exposing the epicotyl, consisting of two primary leaves and the apical meristem.
• In many dicots, the cotyledons not only supply their food stores to the developing plant but also turn green and make more food by photosynthesis until they drop off.

Nutrition and preparation

Toxicity

Before they are eaten, the raw bean seeds should be boiled for at least ten minutes to degrade a toxic compound - the lectin phytohaemagglutinin - found in the bean which would otherwise cause severe gastric upset. This compound is present in many varieties (and in some other species of bean), but is especially concentrated in red kidney beans. Although in the case of dry beans the ten minutes required to degrade the toxin is much shorter than the hours required to fully cook the beans themselves, outbreaks of poisoning have been associated with the use of slow cookers whose low cooking temperatures may be unable to degrade the toxin. Sprouts of pulses high in haemaglutins should not be eaten. Red kidney beans, especially, should not be sprouted.

Dry beans

Similar to other beans, the common bean is high in starch, protein and dietary fiber and an excellent source of iron, potassium, selenium, molybdenum, thiamine, vitamin B6, and folic acid.

Dry beans will keep indefinitely if stored in a cool, dry place, but as time passes, their nutritive value and flavor degrades and cooking times lengthen. Dried beans are almost always cooked by boiling, often after having been soaked for several hours. While the soaking step is not necessary, it shortens cooking time somewhat and results in a more evenly textured pot of beans. In addition, discarding one or more soaking waters leaches out hard-to-digest complex sugars that can cause flatulence. There are several methods: the power soak method is to boil beans for three minutes, then set aside 2-4 hours, then drain and discard water and proceed with cooking. Common beans take longer to cook than most pulses: cooking times vary from one to four hours but are substantially reduced with pressure cooking. The traditional spice to use with beans is Epazote which is also said to aid digestion, and Kombu (a type of seaweed) can be added to beans as they cook to improve their digestion as well. Salt, sugar, and acidic foods, like tomatoes, will harden uncooked beans and therefore should be added last, after the beans have been completely cooked.

Dry beans may also be bought pre-cooked and canned as refried beans, or whole with water, salt, and sometimes sugar.

Green beans

Main article: Green beans

Green common beans are also called string beans, stringless beans (depending on whether the pod has a tough, fibrous "string" running along its length), or snap beans. Compared to the dry beans, they provide less starch and protein, and more vitamin A and vitamin C. The green beans are often steamed, stir-fried, or baked in casseroles.

Shelling beans

As with other beans, prominently among them lima beans, soybeans, peas, and fava beans, common beans can be used for fresh shell beans, also called shelling beans, which are fully mature beans harvested from the pod before they have begun to dry.

Nutritionally, shell beans are similar to dry beans, but in the kitchen are treated as a vegetable, often steamed, fried, or made into soups.

Popping beans

The nuña is an Andean subspecies, Phaseolus vulgaris subsp. nunas (formerly Phaseolus vulgaris (Nuñas Group)), with round multicolored seeds looking like pigeon eggs. When cooked on high heat the bean explodes, exposing the inner part, in the manner of popcorn and other puffed grains.

Varieties

Many well-known bean varieties belong to this species, and none of the lists below are in any way exhaustive. Both bush and running (pole) varieties exist. The colors and shapes of pods and seeds vary tremendously.

Snap or String beans

Stephen Facciola's Cornucopia lists 130 varieties of Snap beans. Varieties specialized for use as green beans, selected for the succulence and flavor of their pods, are the ones usually grown in the home vegetable garden, and many varieties exist. Pod colour can be green, golden, purple, red, or streaked. Shapes range from thin fillet types to wide romano types and more common types in between. French Haricots verts (green beans) are bred for flavorful pods.

• Blue Lake (green)
• Golden Wax (golden)
• Purple King (purple)
• Dragon's Tongue (streaked)
• Red Swan (red)

Shell beans

Cornucopia lists 37 varieties of Shell beans. The light green Flageolet bean is taken very seriously in France and soon the heirloom Chevrier will come under a controlled label reminiscent of the wine "Appellation d'Origine Controllée" called "Label Rouge". A number of other beans are already produced under this label.

Flageolet bean varieties include:

• Chevrier (the original heirloom)
• Elsa
• Flambeau
• Flamingo

Borlotti beans are dried beans and are called by several names in the U.S. The bean is a medium large tan bean, splashed with red/black to magenta streaks. It is very popular in Italian and Portuguese cuisine.

The American Cranberry bean or Horticultural bean is quite similar if not the same as the Italian borlotti bean.^[1] The pinto beans are not considered the same as borlotti beans.

• True Cranberry (old VT heirloom with a more round shape like a cranberry), traditional ingredient of Succotash

Pinto or mottled beans

The pinto bean (Spanish: frijol pinto, literally "painted bean") is named for its mottled skin (compare pinto horse), hence it is a type of mottled bean.

It is the most common bean in the United States [1] and northwestern Mexico [2], and is most often eaten whole in broth or mashed and refried. Either whole or mashed, it is a common filling for burritos. The young pods may also be used as green beans.

In the Southwest United States, the pinto bean is an important symbol of regional identity, especially among Mexican Americans. Along with the chile, it is one of the official state vegetables of New Mexico (under the name frijol). Pinto bean varieties include:

• Sierra
• Burke
• Othello
• Maverick

Another popular mottled bean is the anasazi.

White beans

The small, white navy bean, also called pea bean or haricot, is popular in England, and traditionally the main bean of Anglo-America, used in such dishes as Boston baked beans.

Navy bean varieties include:

• Robust
• Rainy River
• Michelite
• Sanilac

Other white beans are Cannellini and Great Northern.

Red beans

The kidney bean with its dark red skin is named for its visual resemblance to a kidney. The kidney bean is also known as the red bean, although this usage can cause confusion with other red beans. Sometimes kidney beans are used in the red beans and rice of Louisiana Creole cuisine. Other times small red beans are used. Small red beans are noticibly smaller then Kidney beans, and darker of color. They have a smoother taste and are prefered for cajun cuisine.

Kidney bean varieties include:

• Montcalm
• Wells Red
• Geneva
• New York

Black beans

The small, shiny black turtle bean is especially popular in Latin American cuisine. It is often called simply the black bean (frijol negro in Spanish, feijão preto in Portuguese), although this can cause confusion with other black beans.

The black turtle bean has a dense, meaty texture and flavor reminiscent of mushrooms. (To this we may attribute its popularity in vegetarian dishes, most notably the Mexican-American black bean burrito.) It is a very popular bean in various regions of Brazil, and is used in the national dish, feijoada. It is also a principal ingredient of moros y cristianos, served elsewhere in Latin America.

Black turtle beans have recently been reported to be an extremely good source of nutritional antioxidants.^[2]

Black turtle bean varieties include:

• Domino
• Black Magic
• Blackhawk
• Nighthawk

Pink beans

The most famous pink bean is the Santa Maria pinquito which is commercially grown only on the mesas above Santa Maria and is a necessary ingredient in Santa Maria Tri-tip barbecue.

Yellow beans

Sinaloa Azufrado, Sulphur, Mayocoba, and Peruano are types of yellow beans.

See also

• Bean - for other genera and species of beans
• Dal
• Pulse (legume)
• Azuki bean
• Mung bean
• Chickpea
• Lentil

References

External links

• USAID fact sheet with nutritional information on pinto beans
• Fact sheet with nutritional information on pinto beans at WHFoods.org
• USAID fact sheet with nutritional information on black beans
• Plant lectins
• Introducing FLAGEOLET beans on the Multilingual Multiscript Plantname Database site
• Lost Crops of the Incas, p 174 displays a popped seed of P. vulgaris nunas. (An extremely attractive colour photograph by J. Kucharski featuring many cultivars can be found in Lost Crops of the Incas between p 192 & p 193, unfortunately not shown on web site).
• Video recipe