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Yam is the common name for some species in the genus Dioscorea (family Dioscoreaceae). These are perennial herbaceous vines cultivated for the consumption of their starchy tubers in Africa, Asia, Latin America and Oceania. They are used in a fashion similar to potatoes and sweet potatoes. There are hundreds of cultivars among the cultivated species. Download high resolution version (800x686, 79 KB)Yams at Brixton market. ...
Download high resolution version (800x686, 79 KB)Yams at Brixton market. ...
Brixton is an area of South London, England, part of the London Borough of Lambeth. ...
For the Levantine god of the untamed sea, see Yaw. ...
Genera Dioscorea Stenomeris Tacca Trichopus Dioscoreaceae are a family of monocot flowering plants. ...
Red Valerian, a perennial plant. ...
This article is about the plants used in cooking and medicine. ...
This article or section does not cite any references or sources. ...
Starch (CAS# 9005-25-8, chemical formula (C6H10O5)n,[1]) is a mixture of amylose and amylopectin (usually in 20:80 or 30:70 ratios). ...
For fungal genus, see tuber (genus). ...
A world map showing the continent of Africa Africa is the worlds second-largest and second most-populous continent, after Asia. ...
For other uses, see Asia (disambiguation). ...
Latin America consists of the countries of South America and some of North America (including Central America and some the islands of the Caribbean) whose inhabitants mostly speak Romance languages, although Native American languages are also spoken. ...
For other uses, see Oceania (disambiguation). ...
For other uses, see Potato (disambiguation). ...
Binomial name L. Percentages are relative to US recommendations for adults. ...
This Osteospermum Pink Whirls is a successful cultivar. ...
The word yam comes from Portuguese inhame or Spanish ñame, which both ultimately derive from the Wolof word nyam, meaning "to sample" or "taste", in other African languages it can also mean "to eat" e.g. yamyam and nyama in Hausa.[1] Wolof is a language spoken in Senegal, the Gambia, and Mauritania, and it is the native language of the ethnic group of the Wolof people. ...
Hausa is the Chadic language with the largest number of speakers, spoken as a first language by about 24 million people, and as a second language by about 15 million more. ...
Yam tubers can grow up to 2.5 meters in length[2] and weigh up to 70 kg (150 pounds).
The vegetable has a rough skin which is difficult to peel, but which softens after heating. The skins vary in color from dark brown to light pink.
The majority of the vegetable is composed of a much softer substance known as the "meat". This substance ranges in color from white to bright orange in ripe yams. Image File history File links Flag_of_Nigeria. ...
Image File history File links Flag_of_Ghana. ...
Image File history File links Flag_of_Cote_d'Ivoire. ...
Image File history File links Flag_of_Benin. ...
Image File history File links Flag_of_Togo. ...
Image File history File links Flag_of_Colombia. ...
FAO emblem With its headquarters in Rome, the Food and Agriculture Organization (FAO) is a specialized agency of the United Nations that works to raise levels of nutrition and standards of living; to improve the production, processing, marketing, and distribution of food and agricultural products; to promote rural development; and...
Image File history File links Size of this preview: 800 × 351 pixelsFull resolution (1425 × 625 pixels, file size: 57 KB, MIME type: image/png)This bubble map shows the global distribution of yam output in 2005 as a percentage of the top producer (Nigeria - 34,000,000 tonnes). ...
Image File history File links Size of this preview: 800 × 351 pixelsFull resolution (1425 × 625 pixels, file size: 57 KB, MIME type: image/png)This bubble map shows the global distribution of yam output in 2005 as a percentage of the top producer (Nigeria - 34,000,000 tonnes). ...
Yams are a primary agricultural commodity in West Africa and New Guinea. They were first cultivated in Africa and Asia about 8000 B.C. Western Africa (UN subregion) Maghreb[1] West Africa or Western Africa is the westernmost region of the African continent. ...
Yams are important to this day for survival in these regions. The tubers can be stored up to six months without refrigeration, which makes them a valuable resource for the yearly period of food scarcity at the beginning of the wet season. The wet season is a term commonly used when describing the weather in the tropics. ...
Yams are used as food plants by the larvae of some Lepidoptera species including Palpifer sordida. A larval insect A larva (Latin; plural larvae) is a juvenile form of animal with indirect development, undergoing metamorphosis (for example, insects or amphibians). ...
The order Lepidoptera is the second most speciose order in the class Insecta and includes the butterflies, moths and skippers. ...
Palpifer is a genus of moths of the family Hepialidae. ...
Preparation
 Tongan farmer showing off his prize yams Yams of African species must be cooked to be safely eaten, because various natural substances in raw yams can cause illness if consumed; the most common cooking method in Western and Central Africa is fufu. Preparing some species of yam is a time-consuming process, involving days of pounding, leaching, and boiling to remove the toxins. Yams may be served fried, boiled or pounded into a paste. In the Philippines, the purple ube variety of yam (Dioscorea alata, also known in India as ratalu or violet yam) is eaten as a sweetened dessert called halaya, and is also an ingredient in another Filipino dessert, halo halo. Image File history File links Download high-resolution version (458x645, 49 KB) Summary Tongan farmer showing off his prize yams; his wife wears a kiekie-vana; photo James Foster, 1986 Licensing File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old...
Image File history File links Download high-resolution version (458x645, 49 KB) Summary Tongan farmer showing off his prize yams; his wife wears a kiekie-vana; photo James Foster, 1986 Licensing File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old...
Western Africa (UN subregion) Maghreb[1] West Africa or Western Africa is the westernmost region of the African continent. ...
Young women in preparing Fufu in Democratic Republic of Congo Fufu, also spelled foofoo, foufou, or fu fu, is a staple food of West and Central Africa. ...
Binomial name Dioscorea alata L. A piece of cake made with ube Ube (or ubi) is the Filipino word for purple yam (Dioscorea alata). ...
Halo-halo Halo-halo (from Tagalog halo, mix) is a popular Filipino dessert that is a mixture of shaved ice and milk to which are added various boiled sweet beans and fruits, and served cold in a tall glass or bowl. ...
An exception to the cooking rule is the Japanese mountain yam (Dioscorea opposita), known as nagaimo or yamaimo depending on the root shape. Segment of a Dioscorea opposita tuber Grated Dioscorea opposita (Japanese tororo) Tororo udon Dioscorea opposita (also Dioscorea batatas, Dioscorea japonica, Dioscorea polystachya, Dioscorea oppositifolia, nagaimo, yamaimo, Chinese yam, Japanese mountain yam, Korean yam) is a type of yam (Dioscoreaceae) that may be eaten raw. ...
It is eaten raw and grated, after only a relatively minimal preparation: the whole tubers are briefly soaked in a vinegar-water solution, to neutralize irritant oxalate crystals found in their skin. Image File history File linksMetadata Download high-resolution version (1800x1200, 403 KB) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Yam (vegetable) Metadata This file contains additional information, probably added from the digital camera or scanner used to...
Image File history File linksMetadata Download high-resolution version (1800x1200, 403 KB) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Yam (vegetable) Metadata This file contains additional information, probably added from the digital camera or scanner used to...
Port Vila (population 29,356, coordinates ) is the capital city of Vanuatu. ...
An oxalate (called also: ethanedioate) is a salt or ester of oxalic acid. ...
The raw vegetable is starchy and bland, mucilaginous when grated, and may be eaten plain as a side dish, or added to noodles. Mucilage is a thick gluey substance, often produced by plants. ...
'Yam powder' is available in the West from grocers specialising in African products, and may be used in a similar manner to instant mashed potato powder, although preparation is a little more difficult because of the tendency to form lumps. (The best way to eliminate the lumps is to make a very stiff paste with as little hot water as possible, and then press out the lumps, before diluting with more hot water to achieve normal consistency.) The 'yam powder' is sprinkled onto a pan containing a small amount of boiling water, and stirred vigorously.
The resulting mixture is more filling than mashed potatoes, and can make an agreeable meal if warmed cooking sauce, preferably tomato and chilli, is poured onto it.
Cultural aspects The coming of the yams (one of the numerous versions from Maré) is described in Pene Nengone (Loyalty Islands - New Caledonia) [2] Maré is one of the three main islands in the Loyalty Islands and a municipality in the Islands Province of New Caledonia. ...
The Loyalty Islands. ...
In many societies yams are so important that one can speak of a 'yam culture'. Growing the tuber is associated with magic; the best ones must be given to the chief or king; there is a series of myths connected to a divine origin; a farmer may gain a lot of prestige by growing the largest or longest yam; etc.
In many cultures the yam is considered the most sensual of the tubers.[citation needed]. Here are some examples of where this applies:
In Tonga, the ancient names of the months of the year, and the names of the days of the moon-month, were all geared towards the growing of yam. On the Japanese island of Rishiri, yams and yam products are regarded as a folk remedy for the treatment of impotence, presumably because of the vegetable's high vitamin E content. World Class Surf of Pohnpeis Palikir Pass a. ...
Map showing Melanesia. ...
Carving from the ridgepole of a MÄori house, ca 1840 Polynesia (from Greek: πολÏÏ‚ many, νῆσος island) is a large grouping of over 1,000 islands scattered over the central and southern Pacific Ocean. ...
Rishiri Island (利尻島, rishiritÅ) rises out of the Sea of Japan off the coast of Hokkaido, Japan. ...
A home remedy is a treatment or cure for a disease or other ailment that employs certain foods or other common household items. ...
Tocopherol, or Vitamin E, is a fat-soluble vitamin in eight forms that is an important antioxidant. ...
Major cultivated species
 Young women preparing fufu in Democratic Republic of Congo Image File history File links Fufuprep. ...
Image File history File links Fufuprep. ...
Dioscorea rotundata and D. cayenensis Dioscorea rotunda, the white yam, and Dioscorea cayenensis, the yellow yam, are native to Africa. They are the most important cultivated yams. In the past they were considered two species but most taxonomists now regard them as the same species. There are over 200 cultivated varieties between them.
They are large plants; the vines can be as long as 10 to 12 meters (35 to 40 feet). The tubers most often weigh about 2.5 to 5 kg (6 to 12 lbs) each but can weigh as much as 25 kg (60 lbs). After 7 to 12 months growth the tubers are harvested. In Africa most are pounded into a paste to make the traditional dish "fufu" (Kay 1987).
Young women in preparing Fufu in Democratic Republic of Congo Fufu, also spelled foofoo, foufou, or fu fu, is a staple food of West and Central Africa. ...
A piece of cake made with Ube (water yam). Image File history File links Ube_Cake. ...
Image File history File links Ube_Cake. ...
D. alata Dioscorea alata, called water yam, winged yam, and purple yam, was first cultivated somewhere in Southeast Asia. Although it is not grown in the same quantities as the African yams it has the largest distribution world-wide of any cultivated yam, being grown in Asia, the Pacific islands, Africa, and the West Indies (Mignouna 2003). In the United States it has become an invasive species in some Southern states. Binomial name Dioscorea alata L. A Piece of Cake Made With Ube. ...
In the Philippines it is known as ube (or ubi) and is used as an ingredient in many sweet desserts. In India, it is known as ratalu or violet yam or the Moraga Surprise. In Hawaii it is known as uhi. Official language(s) English, Hawaiian Capital Honolulu Largest city Honolulu Area Ranked 43rd - Total 10,931 sq mi (29,311 km²) - Width n/a miles (n/a km) - Length 1,522 miles (2,450 km) - % water 41. ...
Uhi was brought to Hawaii by the early Polynesian settlers and became a major crop in the 1800s when the tubers were sold to visiting ships as an easily stored food supply for their voyages (White 2003).
 Segment of a Dioscorea opposita tuber Image File history File linksMetadata Download high-resolution version (906x632, 153 KB) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Yam (vegetable) Dioscorea opposita Metadata This file contains additional information, probably added from the digital camera or scanner...
Image File history File linksMetadata Download high-resolution version (906x632, 153 KB) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Yam (vegetable) Dioscorea opposita Metadata This file contains additional information, probably added from the digital camera or scanner...
D. opposita Dioscorea opposita, Chinese yam, is native to China. It is tolerant to frost and can be grown in much cooler conditions than other yams. It is now grown in China, Korea, and Japan. It was introduced to Europe in the 1800s when the potato crop there was falling victim to disease. It is still grown in France for the Asian food market. The Chinese yam plant is somewhat smaller than the African yam, with the vines about 3 meters (10 feet) long. The tubers are harvested after about 6 months of growth. Some are eaten right after harvesting and some are used as ingredients for other dishes, including noodles, and for traditional medicines (Kay 1987). Segment of a Dioscorea opposita tuber Grated Dioscorea opposita (Japanese tororo) Tororo udon Dioscorea opposita (also Dioscorea batatas, Dioscorea japonica, Dioscorea polystachya, Dioscorea oppositifolia, nagaimo, yamaimo, Chinese yam, Japanese mountain yam, Korean yam) is a type of yam (Dioscoreaceae) that may be eaten raw. ...
For other uses, see Potato (disambiguation). ...
Image File history File linksMetadata Download high-resolution version (1224x1632, 1389 KB) Dioscorea bulbifera From: Hawaiian Ecosystems at Risk project, http://www. ...
Image File history File linksMetadata Download high-resolution version (1224x1632, 1389 KB) Dioscorea bulbifera From: Hawaiian Ecosystems at Risk project, http://www. ...
D. bulbifera Dioscorea bulbifera, the air potato, is found in both Africa and Asia with slight differences between those found in the two places. It is a large vine 6 meters (20 ft) or more in length. It produces tubers; however the bulbils which grow at the base of its leaves are the more important food product. They are about the size of potatoes (hence the name air potato) weighing from 0.5 to 2 kg (1 to 5 lbs). Some varieties can be eaten raw while some require soaking or boiling for detoxification before eating. It is not grown much commercially since the flavor of other yams is preferred by most people. However it is popular in home vegetable gardens because it produces a crop after only 4 months of growth and continues for the life of the vine, as long as two years. Also the bulbils are easy to harvest and cook (Kay 1987). Binomial name Dioscorea bulbifera L. Dioscorea bulbifera is the scientific name for a species of yam commonly known as the air potato. ...
In 1905 the air potato was introduced to Florida and has since become an invasive species in much of the state. Its rapid growth crowds out native vegetation and is very difficult to remove since it can grow back from the tubers and new vines can grow from the bulbils even after being cut down or burned (Schultz 1993). Lantana invasion of abandoned citrus plantation; Moshav Sdey Hemed, Israel The term invasive species refers to a subset of introduced species or non-indigenous species that are rapidly expanding outside of their native range. ...
D. esculenta Dioscorea esculenta, the lesser yam, was one of the first yam species cultivated. It is native to Southeast Asia and is the third most commonly cultivated species there, although it is cultivated very little in other parts of the world. Its vines seldom reach more than 3 meters (10 feet) in length and the tubers are fairly small in most varieties. The tubers are eaten baked, boiled, or fried much like potatoes. Because of the small size of the tubers mechanical cultivation is possible; which, along with its easy preparation and good flavor, could help the lesser yam to become more popular in the future (Kay 1987). Binomial name L. Dioscorea esculenta is a yam species, but with a smaller corm than most other yams--closer in size to a potato or kumara. ...
D. trifida Dioscorea trifida, the cush-cush yam, is native to the Guyana region of South America and is the most important cultivated New World yam. Since they originated in tropical rain forest conditions their growth cycle is less related to seasonal changes than other yams. Because of their relative ease of cultivation and their good flavor they are considered to have a great potential for increased production (Kay 1987). Binomial name L. The climbing perennial vine Dioscorea trifida is a species of yam native to the Caribbean and tropical Central and South America. ...
South America South America is a continent crossed by the equator, with most of its area in the Southern Hemisphere. ...
Image File history File linksMetadata Download high-resolution version (1136x852, 382 KB) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Yam (vegetable) Metadata This file contains additional information, probably added from the digital camera or scanner used to...
Image File history File linksMetadata Download high-resolution version (1136x852, 382 KB) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Yam (vegetable) Metadata This file contains additional information, probably added from the digital camera or scanner used to...
D. dumetorum Dioscorea dumetorum, the bitter yam, is popular as a vegetable in parts of West Africa; one reason being that their cultivation requires less labor than other yams.
The wild forms are very toxic and are sometimes used to poison animals when mixed with bait. It is said that they have also been used for criminal purposes (Kay 1987).
Nutritional value Yams are high in Vitamin C, dietary fiber, Vitamin B6, potassium, and manganese; while being low in saturated fat, sodium, and cholesterol. Vitamin C, dietary fiber and Vitamin B6 may all promote good health[3]. Furthermore, a product that is high in potassium and low in sodium is likely to produce a good potassium-sodium balance in the human body, and so protect against osteoporosis and heart disease[4]. Having a low level of saturated fat is also helpful for protection against heart disease[5].
Yam products generally have a lower glycemic index than potato products[6], which means that they will provide a more sustained form of energy, and give better protection against obesity and diabetes[7]. Glycemic index (also glycaemic index, GI) is a ranking system for carbohydrates based on their effect on blood glucose levels. ...
Other uses of the term yam In the United States, sweet potatoes (Ipomoea batatas) are often referred to as "yams". Sweet potatoes labeled as "yams" are widely available in markets such as those that serve Asian or Caribbean communities. Binomial name Ipomoea batatas Linnaeus, The sweet potato (Ipomoea batatas) is a crop plant whose large, starchy, sweet-tasting tuberous roots are an important root vegetable. ...
Species I. alba- Moonflower I. aquatica- Water spinach I. batatas- Sweet potato I. purpurea I. violacea - Beach morning glory The Genus Ipomoea, with over 500 species, is the largest genus in the Family Convolvulaceae. ...
In contrast, people in New Zealand sometimes use the word "yam" to refer to the oca (Oxalis tuberosa), and the word "kumara" to refer to the sweet potato. OCA can mean: Observatoire de la Côte dAzur Orthodox Church in America Oxford Capacity Analysis Online Crash Analysis See also Oca This is a disambiguation page — a list of pages that otherwise might share the same title. ...
References - Brand-Miller, J., Burani, J., Foster-Powell, K. (2003). The New Glucose Revolution - Pocket Guide to The Top 100 Low GI Foods. ISBN 1-56924-500-2.
- Consultative Group on International Agricultural Research (CGIAR) (1994). A Breakthrough in Yam Breeding.
- Consultative Group on International Agricultural Research (CGIAR) (2006). Yam.
- Holford, P. (1998). The Optimum Nutrition Bible. ISBN 0-7499-1855-1.
- Huxley, A., ed. (1992). New RHS Dictionary of Gardening. Macmillan.
- Kay, D.E. (1987). Root Crops. Tropical Development and Research Institute : London
- Mignouna, H.D., Abang, M.M., & Asiedu, R. (2003). Harnessing modern biotechnology for tropical tuber crop improvement: Yam (Dioscorea spp.) molecular breeding. Available online.
- Schultz, G.E. (1993). Element Stewardship Abstract for Dioscorea bulbifera, Air potato. Nature Conservancy
- Walsh, S. (2003). Plant Based Nutrition and Health. ISBN 0-907337-26-0.
- White, L.D. (2003). Canoe Plants of Ancient Hawai'i: Uhi
- ^ fr.wikipedia.org/wiki/Igname from Wikipedia in French
- ^ Huxley, 1992
- ^ Holford, ch 11, The Vitamin Scandal ; Walsh, p56
- ^ Walsh, p54; Walsh, pp165-6
- ^ Walsh, ch 8, Fats for health
- ^ Brand-Miller et al, ch 5, The Top 100 Low-GI Foods
- ^ Brand-Miller et al, Introduction
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