Buckwheat (Fagopyrum esculentum) is a plant cultivated for its grain-like seeds, and also used as a cover crop. Despite the name, buckwheat is not related to wheat, as it is not a grass; instead, buckwheat is related to sorrel, knotweed, and rhubarb. The cultivation of buckwheat grain declined sharply in the 20th century with the adoption of nitrogen fertilizer that increased the productivity of other staples. A related species, Fagopyrum tataricum (Tartary buckwheat) is also cultivated as a grain in the Himalayas.
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.
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.
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. Buckwheat is documented in Europe in the Balkans by at least the Middle Neolithic (circa 4000 BC). In Russian, buckwheat is called гречиха (grechikha) meaning Greek, due to its introduction in the 7th century by the Byzantine Greeks.
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 
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. 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.
Historical data 
A century ago, Russia was the world leader in buckwheat production. 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). In 1970, the Soviet Union grew an estimated 4.5 million acres (18,000 km²) of buckwheat. Production in China expanded greatly during the 2000s, to rival Russia's output.
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 annual production statistics were gathered by USDA, only 50,000 acres (200 km2) were grown.
Present-day production 
|Country||Area Harvested (Ha)||Production (tonnes)|
|United States of America||77,244||79,554|
|Republic of Korea||2,446||2,370|
|Bosnia and Herzegovina||584||926|
|Republic of Moldova||385||239|
Chemical composition 
- 71–78% in groats
- 70–91% in different types of flour
- Starch is 25% amylose and 75% amylopectin.
- Depending on hydrothermal treatment, buckwheat groats contain 7–37% of resistant starch.
- Crude protein is 18%, with biological values above 90%. This can be explained by a high concentration of all essential amino acids, especially lysine, threonine, tryptophan, and the sulphur-containing amino acids.
- Antioxidants in the form of phenolics
- Aromatic compounds
Salicylaldehyde (2-hydroxybenzaldehyde) was identified as a characteristic component of buckwheat aroma. 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.
- 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)
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), 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. 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 "grechka" by Russian immigrants. 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. 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. Buckwheat flour is also used to make Nepali dishes like "dhedo" and "kachhyamba".
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 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. 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". 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.
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.
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.
Biological control 
Buckwheat is currently being studied and used as a pollen and nectar source to increase natural enemy numbers to control crop pests in New Zealand.
On Hindu fasting days (Navaratri, Ekadashi, Janamashthami, and Maha Shivaratri), northern states of India eat items made of buckwheat flour. Eating cereals such as wheat or rice is prohibited during such fasting days. However, since buckwheat is not a cereal, it is considered acceptable for consumption during Hindu fasting days. While strong-willed Hindus do not even drink water during their fast (observing nirjal upwaas), others just give up cereals and salt and take a meal made of preparations from non-cereal ingredients such as buckwheat (Kuttu). The preparation of buckwheat flour varies across India. The famous ones are kuttu ki puri (buckwheat pancakes) and kuttu pakoras (potato slices dipped in buckwheat flour and deep fried in oil). In most of northern and western states, buckwheat flour is called kuttu ka atta. In Punjab, it is also called okhla, and is extensively used in flour form.
The buckwheat plant is celebrated in Kingwood, West Virginia 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.
Medicinal uses 
Buckwheat contains a glucoside called rutin, a phytochemical that strengthens capillary walls. One clinical study showed mixed results in the treatment of chronic venous insufficiency. Dried buckwheat leaves were manufactured in Europe under the brand name "Fagorutin" for use as a tisane.
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. 
High protein buckwheat flour is being studied for possible use as a functional ingredient in foods to reduce plasma cholesterol, body fat, and cholesterol gallstones.
See also 
- Eriogonum, a genus of wild North American plants also known as buckwheats
- http://www.etymonline.com/index.php?term=buckwheat Online Etymology Dictionary; W. Martin, G. A. J. Tops, Van Dale Groot woordenboek Engels-Nederlands (Utrecht/Antwerp: Van Dale, 1989), entry "buckwheat".
- Ohnishi, O., Matsuoka, Y. (1996). "Search for the wild ancestor of buckwheat II. Taxonomy of Fagopyrum (Polygonaceae) species based on morphology, isozymes and cpDNA variability". Genes and Genetic Systems 71 (6): 383–390. doi:10.1266/ggs.71.383.
- Ohnishi, O (1998). "Search for the wild ancestor of buckwheat III. The wild ancestor of cultivated common buckwheat, and of tatary buckwheat". Economic Botany 52 (2): 123–133. doi:10.1007/BF02861199.
- T. Björkman, R.R. Bellinder, R.R. Hahn and J Shail (2008). Buckwheat cover crop handbook. Cornell University.
- William Pokhlyobkin. "The Plight of Russian Buckwheat". (Russian) Title in Russian: Тяжёлая судьба русской гречихи
- J. R. N. Taylor, P. S. Belton (2002). Pseudocereals and Less Common Cereals. Springer. p. 125. ISBN 3-540-42939-5.
- Food and Agriculture Association of the United Nations http://faostat3.fao.org
- Skrabanja V, Kreft I, Golob T, Modic M, Ikeda S, Ikeda K, Kreft S, Bonafaccia G, Knapp M, Kosmelj K. (2004). "Nutrient content in buckwheat milling fractions". Cereal Chemistry 81 (2): 172–176. doi:10.1094/CCHEM.2004.81.2.172.
- Skrabanja V, Laerke HN, Kreft I (September 1998). "Effects of hydrothermal processing of buckwheat Fagopyrum esculentum Moench) groats on starch enzymatic availability in vitro and in vivo in rats". Journal of Cereal Science 28 (2): 209–214. doi:10.1006/jcrs.1998.0200.
- Skrabanja V, Elmstahl HGML, Kreft I, Bjorck IME (January 2001). "Nutritional properties of starch in buckwheat products: Studies in vitro and in vivo". Journal of Agricultural and Food Chemistry 49 (1): 490–496. doi:10.1021/jf000779w. PMID 11170616.
- Eggum BO, Kreft I, Javornik B (1980). "Chemical-Composition and Protein-Quality of Buckwheat (Fagopyrum esculentum Moench)". Qualitas Plantarum Plant Foods for Human Nutrition 30 (3–4): 175–9. doi:10.1007/BF01094020.
- Buckwheat Profile
- Bonafaccia G, Marocchini M, Kreft I (2003). "Composition and technological properties of the flour and bran from common and tartary buckwheat". Food Chemistry 80 (1): 9–15. doi:10.1016/S0308-8146(02)00228-5.
- S. Ikeda, Y. Yamashita and I. Kreft (2000). "Essential mineral composition of buckwheat flour fractions". Fagopyrum 17: 57–61.
- Bonafaccia, L. Gambelli, N. Fabjan and I. Kreft (October 2003). "Trace elements in flour and bran from common and tartary buckwheat". Food Chemistry 83 (1): 1–5. doi:10.1016/S0308-8146(03)00228-0.
- Kreft S, Knapp M, Kreft I (November 1999). "Extraction of rutin from buckwheat (Fagopyrum esculentum Moench) seeds and determination by capillary electrophoresis". Journal of Agricultural and Food Chemistry 47 (11): 4649–52. doi:10.1021/jf990186p. PMID 10552865.
- Report on cereals at phenol-explorer.eu
- Janes D, Kreft S (2008). "Salicylaldehyde is a characteristic aroma component of buckwheat groats". Food Chemistry 109 (2): 293–8. doi:10.1016/j.foodchem.2007.12.032.
- Janes D, Kantar D, Kreft S, Prosen H (1. January 2009). "Identification of buckwheat (Fagopyrum esculentum Moench) aroma compounds with GC-MS". Food Chemistry 112 (1): 120–4. doi:10.1016/j.foodchem.2008.05.048.
- Horbowicz M, Brenac P, Obendorf RL.Fagopyritol B1, O-alpha-D-galactopyranosyl-(1-->2)-D-chiro-inositol, a galactosyl cyclitol in maturing buckwheat seeds associated with desiccation tolerance. Planta. 1998 May;205(1):1-11.
- Kreft S, Strukelj B, Gaberscik A, Kreft I (August 2002). "Rutin in buckwheat herbs grown at different UV-B radiation levels: comparison of two UV spectrophotometric and an HPLC method". J Exp Bot 53 (375): 1801–4. doi:10.1093/jxb/erf032. PMID 12147730.
- Eguchi K, Anase T and Osuga H (2009). "Development of a High-Performance Liquid Chromatography Method to Determine the Fagopyrin Content of Tartary Buckwheat (Fagopyrum tartaricum Gaertn.) and Common Buckwheat (F. esculentum Moench)". Plant Production Science 12 (4): 475–480. doi:10.1626/pps.12.475.
- Ožbolt L, Kreft S, Kreft I, Germ M and Stibilj V (2008). "Distribution of selenium and phenolics in buckwheat plants grown from seeds soaked in Se solution and under different levels of UV-B radiation". Food Chemistry 110 (3): 691–6. doi:10.1016/j.foodchem.2008.02.073.
- P. S. Belton; John Reginald Nuttall Taylor (2002). Pseudocereals and Less Common Cereals : grain properties and utilization potential. Springer. p. 138. ISBN 3-540-42939-5.
- "Gluten Free Diet". Celiac Disease Center. University of Chicago. Retrieved 2009-03-31.
- Schiffner R, Przybilla B, Burgdorff T, Landthaler M, Stolz W (October 2001). "Anaphylaxis to buckwheat". Allergy 56 (10): 1020–1. doi:10.1034/j.1398-9995.2001.00386.x. PMID 11576091.
- Lee SY, Oh S, Lee K, et al. (August 2005). "Murine model of buckwheat allergy by intragastric sensitization with fresh buckwheat flour extract". J. Korean Med. Sci. 20 (4): 566–72. doi:10.3346/jkms.2005.20.4.566. PMC 2782149. PMID 16100445.
- Heffler E, Guida G, Badiu I, Nebiolo F, Rolla G (2007). "Anaphylaxis after eating Italian pizza containing buckwheat as the hidden food allergen". J Investig Allergol Clin Immunol 17 (4): 261–3. PMID 17694699.
- Heffler E, Nebiolo F, Asero R, et al. (August 2010). "Clinical manifestations, co-sensitizations, and immunoblotting profiles of buckwheat-allergic patients". Allergy 42 (3): 181–7. doi:10.1111/j.1398-9995.2010.02469.x. PMID 2080447.
- Carolyn Smagalski (2006). "Gluten Free Beer Festival".
- Chein Soo Hong, Hae Sim Park and Seung Heon Oh (December 1987). "Dermatophagoides Farinae, an Important Allergenic Substance in Buckwheat-Husk Pillows" (PDF). Yonsei Medical Journal 28 (4): 274–281.
- Hae-Seon Nam, Choon-Sik Park, Julian Crane, Rob Siebers (2004). "Endotoxin and House Dust Mite Allergen Levels on Synthetic and Buckwheat Pillows" (PDF). Journal of Korean Medical Science 19 (4): 505–8. doi:10.3346/jkms.2004.19.4.505. ISSN 1011-8934. PMC 2816881. PMID 15308838.
- Berndt LA, Wratten SD, Hassan PG (2002). "Effects of buckwheat flowers on leafroller (Lepidoptera: Tortricidae) parasitoids in a New Zealand vineyard". Agricultural and Forest Entomology 4 (1): 39–45. doi:10.1046/j.1461-9563.2002.00126.x.
- Griffith, J.Q.; J.F. Couch, M. A. Lindauer (1944). "Effect of Rutin on Increased Capillary Fragility". Proc Soc Exp Biol Med March 55: 228–229.
- Ihme, N.; H. Kiesewetter, F. Jung, K. H. Hoffmann, A. Birk, A. Müller, K. I. Grützner (1996-07-12). "Leg oedema protection from a buckwheat herb tea in patients with chronic venous insufficiency: a single-centre, randomised, double-blind, placebo-controlled clinical trial". Eur J Clin Pharmacol 50 (6): 443–447. doi:10.1007/s002280050138. PMID 8858269.
- Identification of galloylated propelargonidins and procyanidins in buckwheat grain and quantification of rutin and flavanols from homostylous hybrids originating from F. esculentum × F. homotropicum. Carolin Ölschläger, Ionela Regos, Friedrich J. Zeller and Dieter Treutter, doi:10.1016/j.phytochem.2008.01.001
- Kawa, J.M., Taylor, C.G., Przybylski, R. (2003). "Buckwheat Concentrate Reduces Serum Glucose in Streptozotocin-Diabetic Rats". J. Agric. Food Chem 50 (25): 443–7. doi:10.1021/jf0302153.
- Y. Yao, F. Shan, J. Bian, F. Chen, M. Wang and G. Ren (2008). "d-chiro-Inositol-Enriched Tartary Buckwheat Bran Extract Lowers the Blood Glucose Level in KK-Ay Mice". J. Agric. Food Chem 56 (21): 10027–10031. doi:10.1021/jf801879m. PMID 18921966.
- Nestler JE, Jakubowicz DJ, Reamer P, Gunn RD, Allan G (1999). "Ovulatory and metabolic effects of D-chiro-inositol in the polycystic ovary syndrome". N. Engl. J. Med. 340 (17): 1314–20. doi:10.1056/NEJM199904293401703. PMID 10219066.
- Iuorno MJ, Jakubowicz DJ, Baillargeon JP, et al. (2002). "Effects of d-chiro-inositol in lean women with the polycystic ovary syndrome". Endocrine practice 8 (6): 417–23. PMID 15251831.
- Tomotake, H.; Yamamoto, N.; Yanaka, N.; Ohinata, H.; Yamazaki, R.; Kayashita, J.; Kato, N. (2006). "High protein buckwheat flour suppresses hypercholesterolemia in rats and gallstone formation in mice by hypercholesterolemic diet and body fat in rats because of its low protein digestibility". Nutrition (Burbank, Los Angeles County, Calif.) 22 (2): 166–173. doi:10.1016/j.nut.2005.01.012.
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|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. 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.
- 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. 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 esculentum Moench. Promoting the conservation and use of underutilized and neglected crops. 19. International Plant Genetic Resources Institute, Rome, Italy.
- Descriptors for Buckwheat (Fagopyrum spp.)
- Nutritional information for buckwheat
- Buckwheat (Fagopyrum spp.)
- Fagopyrum Journal Archive
- "Recipe for buckwheat that does not stick". ASAN. Retrieved 2009-05-13.
- "Buckwheat pancakes". BBC. Retrieved 2008-02-26.
- "Buckwheat noodles with smoked salmon and dill". BBC. Retrieved 2008-02-26.
- "Recipe for Buckwheat Porridge". DukeLupus. Retrieved 2008-02-26.