buckwheat

Common Buckwheat
Scientific classification
Kingdom:	Plantae
Order:	Caryophyllales
Family:	Polygonaceae
Genus:	Fagopyrum
Species:	F. esculentum
Binomial name
Fagopyrum esculentum Moench

Buckwheat refers to a variety of plants in the dicot family Polygonaceae: the Eurasian genus Fagopyrum, the North American genus Eriogonum, and the Northern Hemisphere genus Fallopia. Either of the latter two may be referred to as "wild buckwheat." Despite the name, buckwheats are not related to wheat, as they are not cereals / grasses (family Poaceae); instead, buckwheat is related to sorrels, knotweeds, and rhubarb.

The cultivation of buckwheat grain, a pseudocereal food crop, declined sharply in the 20th century in affluent regions where the usage of nitrogen fertilizer is popular.

General

Fagopyrum

The crop plant, common buckwheat, is Fagopyrum esculentum. Tartary buckwheat (F. tataricum Gaertn.) or "bitter buckwheat" is also used as a crop, but it is much less common. Despite the common name and the grain-like use of the crop, buckwheat is not a cereal or grass. The grain is called a pseudocereal to emphasize that the plant is not related to wheat.

Buckwheat plants grow quickly, beginning to produce seed in about 6 weeks and ripening at 10 to 11 weeks. They grow 30 to 50  inches (75 to 125 cm) tall.^[1]

This genus has five-petaled flowers arranged in a compound raceme that produces laterally flowered cymose clusters.^[2]

Within Fagopyrum, the cultivated species are in the cymosum group, with F. cymosum L. (perennial buckwheat), F. giganteum and F. homotropicum.^[3]

Eriogonum

Eriogonum is a common chaparral plant throughout western North America, especially California, where it is the largest genus of dicots^[4] and at least 70 species have been cataloged.^[5] The flowers have six petals and occur in cymes.

Fallopia

The agricultural weed known as 'wild buckwheat' (Fallopia convolvulus) is in the same family, but not closely related to the crop species.

Etymology

The name 'buckwheat' or 'beech wheat' comes from its triangular seeds, which resemble the much larger seeds of the beech nut from the beech tree, and the fact that it is used like wheat. The word may be a translation of Middle Dutch boecweite : boec (modern Dutch beuk), beech (see PIE bhago-) + weite (mod. Dut. weit), wheat; or may be a native formation on the same model as the Dutch word.^[6]

History

Common buckwheat in flower

The wild ancestor of common buckwheat is F. esculentum ssp.ancestrale. F. homotropicum is interfertile with F. esculentum and the wild forms have a common distribution, in Yunnan. The wild ancestor of tartary buckwheat is F. tataricum ssp. potanini.^[7]

Common buckwheat was domesticated and first cultivated in inland southeast Asia, possibly around 6000 BC, and from there spread to Central Asia and Tibet, and then to the Middle East and Europe. Domestication most likely took place in the western Yunnan region of China.^[8] Buckwheat is documented in Europe in the Balkans by at least the Middle Neolithic (circa 4000 BC).

The oldest known remains in China so far date to circa 2600 BC while buckwheat pollen found in Japan dates from as early as 4000 BC. It is the world's highest elevation domesticate, being cultivated in Yunnan on the edge of the Tibetan Plateau or on the Plateau itself. Buckwheat was one of the earliest crops introduced by Europeans to North America. Dispersal around the globe was complete by 2006, when a variety developed in Canada was widely planted in China.

Buckwheat is a short season crop that does well on low-fertility or acidic soils, but the soil must be well drained. Too much fertilizer, especially nitrogen, will reduce yields. In hot climates, it can only be grown by sowing late in the season, so that it will bloom in cooler weather. The presence of pollinators greatly increases the yield. The nectar from buckwheat flower makes a dark-colored honey. Buckwheat is sometimes used as a green manure, as a plant for erosion control, or as wildlife cover and feed.

Agricultural production

Seed and wither flower of buckwheat

Buckwheat is raised for grain where a short season is available, either because it is used as a second crop in the season, or because the climate is limiting. Buckwheat can be a reliable cover crop in summer to fit a small slot of warm season for establishment. It establishes quickly, which suppresses summer weeds.^[1]

Historical data

A century ago, Russia was the world leader in buckwheat production.^[9] Growing areas in the Russian Empire were estimated at 6.5 million acres (26,000 km²), followed by those of France (0.9 million acres; 3,500 km²).^[10] In 1970, the Soviet Union grew an estimated 4.5 million acres (18,000 km²) of buckwheat. China was then the world's top producer until 2005, with Russia becoming once again the top producer after 2007.

In the northeastern United States, buckwheat was a common crop in the 18th and 19th centuries. Cultivation declined sharply in the 20th century due to the use of nitrogen fertilizer, to which maize and wheat respond strongly. Over a million acres (4,000 km²) were harvested in the United States in 1918. By 1954, that had declined to 150,000 acres (610 km²), and by 1964, the last year production statistics were gathered, only 50,000 acres (200 km²) were grown.

Present-day production

Common buckwheat is by far the most important buckwheat species, economically, accounting for over 90% of the world's buckwheat production. World's largest producer of buckwheat now is China ^[11]

This article is outdated. Please update this article to reflect recent events or newly available information. Please see the talk page for more information. (February 2012)

Worldwide buckwheat production in past
(s : semi-official data — e : estimated data — a : aggregated from official and estimated data)^[12]

Buckwheat	Cultivated area (hectares)				Yield (hectograms/ha)				Production (tonnes)				Seed (tonnes)
Countries	2005		2007		2005		2007		2005		2007		2005
Russia	833,600		1,305,000		7,265	e	7,700	e	605,640		1,004,850		69,500	s
China	834,000	e	900,000	e	8,992		8,888		750,000	e	800,000	e	87,570	e
Ukraine	396,200		237,000		6,933	e	6,751	e	274,700		160,000		20,500	s
France	36,593		32,945		33,945	e	35,558	e	124,217		117,148		3,293	e
Poland	67,531		90,000	e	10,675	e	9,777	e	72,096		88,000	e	5,500	e
Kazakhstan	55,000		142,600		10,545	e	5,610	e	58,000	s	80,000	e	3,200	s
United States	65,000	e	68,000	e	10,000	e	10,000	e	65,000	e	68,000	e	2,600	e
Brazil	46,000	e	48,000	e	10,869	e	10,833	e	50,000	e	52,000	e	2,760	e
Japan	44,700		44,600	e	6,979	e	7,623	e	31,200		34,000	e	1,341	e
Lithuania	28,400		21,700		5,528	e	9,631	e	15,700		20,900		2,500	e
Belarus	7,106		11,500		10,227	e	11,304	e	7,268		13,000		1,000	e
Latvia	10,400		13,000	e	9,519	e	6,307	e	9,900		8,200	e
Bhutan	4,500	e	4,600	e	14,888	e	14,782	e	6,700		6,800	e	360	e
South Korea	2,257		2,650	e	9,937	e	11,320	e	2,243		3,000	e	90	e
Canada	4,000		2,000		11,500	e	11,500	e	4,600		2,300		300	e
Czech Republic	1,000	e			20,000	e			2,000	e			26	e
Slovenia	811		809		17,916	e	9,406	e	1,453		761		52	e
Hungary	752		800	e	6,156	e	5,000	e	463		400	e	60	e
Estonia	676		314		7,174	e	9,554	e	485		300
Slovakia	461		500	e	8,872	e	6,000	e	409		300	e
Moldova	2,811		7,200	e	3,429	e	416	e	964		300	e	252	e
Kyrgyzstan	378		600	e	9,179	e	8,333	e	347		500	e
South Africa	1,000	e	1,000	e	3,000	e	3,000	e	300	e	300	e	65	e
Croatia	45	e			31,111	e			140	e			2	e
Georgia	100	e	100	e	10,000	e	10,000	e	100	s	100	e
World	2,443,321	a	2,934,918	a	8,529	e	8,385	e	2,083,925	a	2,461,159	a	200,974	a

Chemical composition

Seeds

Starch

• 71–78% in groats
• 70–91% in different types of flour^[13][14][15]
• Starch is 25% amylose and 75% amylopectin.
• Depending on hydrothermal treatment, buckwheat groats contain 7–37% of resistant starch.

Proteins

• Crude protein is 18%, with biological values above 90%.^[16] This can be explained by a high concentration of all essential amino acids,^[17] especially lysine, threonine, tryptophan, and the sulphur-containing amino acids.^[18]

Minerals

• Rich in iron (60–100 ppm), zinc (20–30 ppm) and selenium (20–50 ppb)^[19][20]

Antioxidants

• 10–200 ppm of rutin and 0.1–2% of tannins^[21]

Aromatic compounds

Salicylaldehyde (2-hydroxybenzaldehyde) was identified as a characteristic component of buckwheat aroma.^[22] 2,5-dimethyl-4-hydroxy-3(2H)-furanone, (E,E)-2,4-decadienal, phenylacetaldehyde, 2-methoxy-4-vinylphenol, (E)-2-nonenal, decanal and hexanal also contribute to its aroma. They all have odour activity value more than 50, but the aroma of these substances in an isolated state does not resemble buckwheat.^[23]

Inositol derivatives

Fagopyritol A1 and fagopyritol B1 (mono-galactosyl D-chiro-inositol isomers), fagopyritol A2 and fagopyritol B2 (di-galactosyl D-chiro-inositol isomers), and fagopyritol B3 (tri-galactosyl D-chiro-inositol) ^[24]

Herb

Antioxidants

• 1–10% rutin and 1–10% tannins^[25]

Fagopyrin

• 0.4 to 0.6 mg/g of fagopyrins (at least 3 similar substances)^[26][27]

Use

Food

Buckwheat porridge

Soba noodles, made from buckwheat flour

Naengmyeon, Korean cold noodle soup made with buckwheat flour

A traditional Breton galette, a thin large buckwheat flour crepe

The fruit is an achene, similar to sunflower seed, with a single seed inside a hard outer hull. The starchy endosperm is white and makes up most or all of buckwheat flour. The seed coat is green or tan, which darkens buckwheat flour. The hull is dark brown or black, and some may be included in buckwheat flour as dark specks. The dark flour is known as blé noir (black wheat) in French, along with the name sarrasin (saracen).

Buckwheat noodles have been eaten by people from Tibet and northern China for a long time, as wheat can not be grown in the mountain regions. A special press made of wood log was built to press the dough into hot boiling water when making buckwheat noodles. Old presses found in Tibet and Shansi share the same basic design features. The Japanese and Koreans might have learned the making of buckwheat noodles from them.

Buckwheat noodles play a major role in the cuisines of Japan (soba),^[28] Korea (naengmyeon, makguksu and memil guksu) and the Valtellina region of Northern Italy (pizzoccheri). Soba noodles are the subject of deep cultural importance in Japan. In Korea, guksu (noodles) were widely made from buckwheat before it was replaced by wheat.^{[citation needed]} The difficulty of making noodles from flour with no gluten has resulted in a traditional art developed around their manufacture by hand.

Buckwheat groats are commonly used in western Asia and eastern Europe. The porridge was common, and is often considered the definitive peasant dish. It is made from roasted groats that are cooked with broth to a texture similar to rice or bulgur. The dish was brought to America by Russian and Polish immigrants who called it kasha, and they mixed it with pasta or used it as a filling for knishes and blintzes, and hence buckwheat prepared in this fashion is most commonly called "kasha" in America, but the groats themselves are called "gretchka" by Russian immigrants.^{[citation needed]} Groats were the most widely used form of buckwheat worldwide during the 20th century, eaten primarily in Russia, Ukraine and Poland. The groats can also be sprouted and then eaten raw or cooked.

Buckwheat pancakes, sometimes raised with yeast, are eaten in several countries. They are known as buckwheat blinis in Russia, galettes in France (savoury crêpes made with buckwheat flour, water and eggs are associated with Lower Brittany, whilst savoury galettes made without eggs are from Higher Brittany), ployes in Acadia and boûketes (which are named after the buckwheat plant) in the Wallonia region of Belgium. Similar pancakes were a common food in American pioneer days.^{[citation needed]} They are light and foamy. The buckwheat flour gives them an earthy, mildly mushroom-like taste. In Ukraine, yeast rolls called hrechanyky are made from buckwheat.

Farina made from groats are used for breakfast food, porridge, and thickening materials in soups, gravies, and dressings. In Korea, buckwheat starch is used to make a jelly called memilmuk. It is also used with wheat, maize (polenta taragna in Northern Italy) or rice in bread and pasta products.

Buckwheat contains no gluten^[29] and can consequently be eaten by people with coeliac disease or gluten allergies. Many bread-like preparations have been developed. However, buckwheat can be a potent and potentially fatal allergen by itself. In sensitive people, it provokes IgE-mediated anaphylaxis.^[30] The cases of anaphylaxis induced by buckwheat ingestion have been reported in Korea, Japan and Europe, where it is more often described as a "hidden allergen".^[31][32] A recent article by Heffler et al. showed allergic reactions, even severe ones, induced by accidental ingestion of buckwheat as "hidden allergy", are not so rare as previously described.^[33]

Buckwheat is a good honey plant, producing a dark, strong^[34] monofloral honey.

Beer

In recent years, buckwheat has been used as a substitute for other grains in gluten-free beer. Although it is not a cereal, buckwheat can be used in the same way as barley to produce a malt that can form the basis of a mash that will brew a beer without gliadin or hordein (together gluten) and therefore can be suitable for coeliacs or others sensitive to certain glycoproteins.^[35]

Medicinal uses

Buckwheat contains a glucoside named rutin, a medicinal chemical that strengthens capillary walls, reducing hemorrhaging in people with high blood pressure and increasing microcirculation in people with chronic venous insufficiency.^[36] Dried buckwheat leaves for tea were manufactured in Europe under the brand name "Fagorutin".

Buckwheat contains D-chiro-inositol, a component of the secondary messenger pathway for insulin signal transduction found to be deficient in Type II diabetes and polycystic ovary syndrome. It is being studied for use in treating Type II diabetes.^[37] Research on D-chiro-inositol and PCOS has shown promising results.^[38][39]

A buckwheat protein has been found to bind cholesterol tightly. It is being studied for reducing plasma cholesterol in people with hyperlipidemia.^[40]

It is rich in dietary fiber and one of the laxative foods.

Upholstery filling

Buckwheat hulls are used as filling for a variety of upholstered goods, including pillows and zafu. The hulls are durable and do not conduct or reflect heat as much as synthetic fills. They are sometimes marketed as an alternative natural fill to feathers for those with allergies. However, medical studies to measure the health effects of buckwheat hull pillows manufactured with unprocessed and uncleaned hulls, concluded such buckwheat pillows do contain higher levels of a potential allergen that may trigger asthma in susceptible individuals than do new synthetic-filled pillows.^[41][42]

Biological control

Buckwheat is currently being researched, and actively used, as a pollen and nectar source to increase natural enemy numbers to control crop pests in New Zealand.^[43]

Festivals

Field of buckwheat in Bumthang (Bhutan) - photo by Italian writer Mario Biondi, September 2010

The buckwheat plant is celebrated in Kingwood, West Virginia, US at their Buckwheat Festival, where people can participate in swine, cattle, and sheep judging contests, vegetable contests, and craft fairs. The area fire departments also play an important role in the series of parades that occur there. Each year there is a King Buckwheat and Queen Ceres elected. Also there are many rides, and homemade, homegrown buckwheat cakes and sausage are served.

Kuttu ka atta

On Hindu fasting days (Navaratri mainly, also Maha Shivaratri), northern states of India eat items made of buckwheat flour, because, unlike wheat or rice, buckwheat is not a cereal, and thus deemed acceptable. Cereals are not generally eaten during Hindu fasts. Rules of the fast are left for the individuals to decide; some people do not drink water during their fast (nirjal upwaas), while some just give up cereals and salt. The preparation varies across India. The famous ones are kuttu ki puri and kuttu pakoras. In most of northern and western states, they call this kuttu ka atta. In Punjab, it is called okhla, too, and is extensively used in flour form.

References

External links

Wikimedia Commons has media related to: Buckwheat

Wikisource has the text of the 1911 Encyclopædia Britannica article Buckwheat.

• E.S. Oplinger, E.A. Oelke, M.A. Brinkman and K.A. Kelling (November 1989). "Buckwheat". Alternative Field Crops Manual. http://www.hort.purdue.edu/newcrop/afcm/buckwheat.html. Retrieved 2008-02-26. 
• Damania, A.B. (1998). "Diversity of Major Cultivated Plants Domesticated in the Near East". Proceedings of the Harlan Symposium. http://www.ipgri.cgiar.org/publications/HTMLPublications/47/ch07.htm. 
• Chun H.N., Chung C.K., Kang I.J., Kim E.R., Kim Y.S. (2003). "Effect of Germination on the Nutritional Value of Buckwheat Seed". Division of Life Sciences at Hallym University, South Korea. http://ift.confex.com/ift/2003/techprogram/paper_17126.htm. 
• Mazza, G. (1992). "Buckwheat (Fagopyrum esculentum), the crop and its importance". In MacRae, R.. Encyclopedia of food science, food technology and nutrition. London: Academic Press Ltd.. pp. 534–9. 
• Mazza, G. (1993). "Storage, Processing, and Quality Aspects of Buckwheat Seed". In Janick J., Simon J.E.. New crops. New York: Wiley. pp. 251–5. 
• Marshall, H.G. and Y. Pomeranz. (1982). "Buckwheat description, breeding, production and utilization". In Y. Pomeranz. Advances in cereal science and technology. St. Paul, MN.: Amer. Assoc. Cereal Chem.. pp. 157–212. 
• McGregor, S.E. (1976). "9 Crop Plants and Exotic Plants — Buckwheat". Insect Pollination Of Cultivated Crop Plants. U.S. Department of Agriculture. http://gears.tucson.ars.ag.gov/book/chap9/buckwheat.html.  As found on the website of the Carl Hayden Bee Research Center of the USDA Agricultural Research Service.
• Multilingual taxonomic information from the University of Melbourne
• Clayton G. Campbell (1997). Buckwheat Fagopyrum esculentus Moench. Promoting the conservation and use of underutilized and neglected crops. 19. International Plant Genetic Resources Institute, Rome, Italy. http://www.bioversityinternational.org/Publications/pubfile.asp?ID_PUB=343. 
• Descriptors for Buckwheat (Fagopyrum spp.)
• Nutritional information for buckwheat
• Buckwheat (Fagopyrum spp.)
• Fagopyrum Journal Archive

Recipes

• "Recipe for buckwheat that does not stick". ASAN. http://www.asiteaboutnothing.net/f_kasha.html. Retrieved 2009-05-13. 
• "Buckwheat pancakes". BBC. http://www.bbc.co.uk/food/recipes/database/buckwheatpancakes_80141.shtml. Retrieved 2008-02-26. 
• "Buckwheat noodles with smoked salmon and dill". BBC. http://www.bbc.co.uk/food/recipes/database/buckwheatnoodleswith_77288.shtml. Retrieved 2008-02-26. 
• "Recipe for Buckwheat Porridge". DukeLupus. http://thisfoodthing.com/2007/07/07/buckwheat-porridge-recipe-by-dukelupus/. Retrieved 2008-02-26.