Wheat seed, sectioned to reveal endosperm and embryo

Wheat — a prime source of gluten

Gluten is a composite of the proteins gliadin and glutenin. Wheat ( Triticum spp is a worldwide cultivated grass from the Levant area of the Middle East. Gliadin is a Glycoprotein present in Wheat and several other Cereals within the grass genus Triticum. Glutenin (or e) is the Glutelin derived from wheat Gluteninis a Protein best known for its role along with Gliadin, in the creation of These exist, conjoined with starch, in the endosperms of some grass-related grains, notably wheat, rye, and barley. Starch, CAS # 9005-25-8 Chemical formula (C6H10O5n is a Polysaccharide Endosperm is the tissue produced in the Seeds of most Flowering plants around the time of fertilization Triticeae glutens are seed storage Proteins found in mature seeds of grass tribe Triticeae. Wheat ( Triticum spp is a worldwide cultivated grass from the Levant area of the Middle East. Rye ( Secale cereale) is a grass grown extensively as a grain and forage crop Barley ( Hordeum vulgare) is an annual Cereal Grain, which serves as a major animal Feed crop, with smaller amounts used for Gliadin and glutenin comprise about 80% of the protein contained in wheat seed. Being insoluble in water, they can be purified by washing away the associated starch. Worldwide, gluten is an important source of nutritional protein, both in foods prepared directly from sources containing it, and as an additive to foods otherwise low in protein.

The seeds of most flowering plants have endosperms with stored protein to nourish embryonic plants during germination, but true gluten, with gliadin and glutenin, is limited to certain members of the grass family. The stored proteins of maize and rice are sometimes called glutens, but their proteins differ significantly from wheat gluten by lacking glutenin. Rice is a Cereal foodstuff which forms an important part of the diet of many people worldwide and as such it is a staple food for many The glutenin in wheat flour gives kneaded dough its elasticity, allowing leavening and contributing chewiness to baked products like bagels. For kneading of clay see wedging Kneading is a process in the making of Bread, used to mix together the ingredients and add strength Dough is a paste made out of any Cereals (grains or leguminous crops by mixing the Flour with a small amount of Water. Viscoelasticity is the property of materials that exhibit both viscous and elastic characteristics when undergoing deformation. A leavening agent (sometimes called just leavening or leaven) is a substance used in Doughs and batters that causes a foaming action intended A bagel is a bread product, traditionally made of Yeasted Wheat dough in the form of a roughly hand-sized ring which is first boiled in water and then baked

Although wheat supplies much of the world's dietary protein and food supply, as many as 0. 5% to 1% of the population of the United States has Celiac disease, a condition which results from an inappropriate immune system response to gluten. The United States of America —commonly referred to as the Coeliac ^[1] The manifestations of celiac disease range from no symptoms to malabsorption of nutrients with involvement of multiple organ systems. The only effective treatment is a lifelong gluten-free diet. A gluten-free diet is recommended amongst other things in the treatment of Coeliac disease and Wheat allergy.

Extraction

Legend attributes the discovery of gluten to Buddhist monks in 7th century China who sought meat-like ingredients for use in their vegetarian diet. A Bhikkhu ( Pāli) or Bhiksu ( Sanskrit) is a fully ordained male Buddhist Monastic. Vegetarianism is the practice of a diet that excludes Meat (including game and slaughter by-products Fish (including Shellfish and other sea ^[2] With easily available wheat flour and water they made a dough which they submerged in cold water and kneaded. The water dissolved the starchy components of the dough and left behind an insoluble, gummy mass, 70% to 80% of which was gluten.

Gluten is still extracted from flour by washing out the starch by means not fundamentally different from the ancient way, which exploited the fact that starch is water-soluble while gluten is not — also, that gluten binds together strongly, while starch dissolved in cold water is mobile. If a saline solution is used instead of water a purer protein is obtained, with certain harmless impurities going into solution with the starch. Salt is a Dietary mineral composed primarily of Sodium chloride that is essential for Animal life but toxic to most land plants However, on an industrial scale, starch is the prime product, so cold water is the favored solvent. To effect the separation, a slurry of wheat flour is stirred vigorously by machinery until the starch dissolves and the gluten consolidates into a mass, which is collected by centrifugation, then carried, by complex machinery,^[3] through several stages combined into a continuous process: Approximately 65% of the water in the wet gluten is removed by means of a screw press, and the residue is sprayed through an atomizing nozzle into a drying chamber, where it remains at an elevated temperature only long enough to evaporate the water without denaturing the gluten. This yields a flour-like powder with a 7% moisture content, which is quickly air-cooled and pneumatically transported to a receiving vessel. In the final step, the collected gluten is sifted and milled to make the product uniform. ^[4]

Uses

When dough made with wheat flour is kneaded, gluten forms when glutenin molecules cross-link to make a sub-microscopic network and associates with gliadin, which contributes viscosity and extensibility to the mix. ^[5] If such dough is leavened with yeast, sugar fermentation produces bubbles of carbon dioxide which, trapped by the gluten network, cause the dough to swell or rise. Yeasts are a growth form of eukaryotic Microorganisms classified in the kingdom Fungi, with about 1500 Species currently described Fermentation in Food processing typically refers to the conversion of Sugar to Alcohol using Yeast under Anaerobic conditions Baking coagulates the gluten, which, along with starch, stabilizes the shape of the final product. Denaturation is a process in which Proteins or Nucleic acids lose their structure (tertiary structure by application of some external stress or compound for Gluten content has been implicated as a factor in the staling of bread, possibly because it binds water by hydration. ^[6]

The development of gluten (i. e. , enhancing its elasticity) affects the texture of the baked goods. Gluten's attainable elasticity is proportional to its content of glutenins with low molecular weights because that fraction contains the preponderance of the sulfur atoms responsible for the cross-linking in the network. ^[7][8] More development leads to chewier products like pizza and bagels, while less development yields tender baked goods. Pizza (ˈpiːtsə, in Italian:) is a popular dish made with an Oven -baked flat generally round Bread that is covered with tomatoes or a tomato-based A bagel is a bread product, traditionally made of Yeasted Wheat dough in the form of a roughly hand-sized ring which is first boiled in water and then baked In general, bread flours are high in gluten while cake flours are low. Kneading promotes the formation of gluten strands and cross-links, so a baked product is chewier in proportion to how much the dough is worked. Increased wetness of the dough also enhances gluten development. ^[9] Shortening inhibits formation of cross-links, so it is used, along with diminished water and minimal working, when a tender and flaky product, such as pie crust, is desired. Shortening is a semisolid Fat used in food preparation especially baked goods and is so called because it promotes a "short" or crumbly texture (as in Shortbread

Gluten, dried and milled to powder and added to ordinary flour dough, improves rising and increases the bread's structural stability and chewiness,^[10]. Such doughs must be worked vigorously if they are to rise to their full capacity, so a bread machine or food processor may be required for their kneading. ^[11] The added gluten provides supplemental protein to what would otherwise be high-carbohydrate preparations. The protein content of pet foods is also enhanced by adding gluten. ^[12] When cooked in broth, gluten absorbs some of the surrounding liquid (including the taste) and becomes firm to the bite, so is widely used in vegetarian, vegan and Buddhist cuisines as a meat substitute. Broth is a Liquid in which Bones Meat, Fish, Cereal grains or Vegetables have been simmered and strained out Vegetarian cuisine refers to Food that meets vegetarian standards by excluding Meat and animal tissue products Buddhist cuisine is a kind of East Asian Cuisine which is followed by some believers of Buddhism. In China, as miàn jin, it is the basis for imitation meats resembling chicken, duck, fish, pork and beef. The Japanese variants, called namafu, yakifu, and seitan, are used in the same way. Wheat gluten, also called seitan ( wheat meat, gluten meat, or simply gluten, is a Food made from the Gluten of

Gluten as an additive

The "Codex Alimentarius" set of international standards for food labeling has a standard relating to the labelling of products as "gluten free", however this standard does not apply to "foods which in their normal form do not contain gluten". The Codex Alimentarius (Latin for "food code" or "food book" is a collection of internationally recognized standards codes of practice guidelines and other recommendations ^[13] Gluten is used as a stablizing agent in products like ice-cream and ketchup, where it may be unexpected. Food additives are substances added to food to preserve flavour or improve its taste and appearance Ice cream or ice-cream (originally iced cream) is a frozen dessert made from Dairy products such as Milk and Cream, combined Ketchup (also spelled catsup or catchup) also known as tomato ketchup, tomato sauce, red sauce, Tommy sauce, ^{[14] [15]} Foods of this kind present a problem because the hidden gluten constitutes a hazard for people with celiac disease: In the United States, at least, gluten may not be listed on the labels of such foods because the U. Coeliac S, Food and Drug Administration has classified gluten as GRAS (Generally recognized as safe). Generally Recognized as Safe ( GRAS) is a United States of America Food and Drug Administration (FDA designation that a chemical or substance added to food ^[16] Requirements for proper labeling are being formulated by the USDA. In the United Kingdom, only cereals currently need to be labelled, while other products are voluntary^[17]. The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom, the UK or Britain,is a Sovereign state located

Adverse reactions

Main article: Gluten sensitivity

Main article: Gluten free diet

Between 0. Gluten sensitivity (GS encompasses a collection of medical conditions in which Gluten has an adverse effect A gluten-free diet is recommended amongst other things in the treatment of Coeliac disease and Wheat allergy. 5 and 1. 0 percent of people in the United States are sensitive to gluten ^{[18] [19]} Coeliac disease (or celiac disease, also called gluten sensitive enteropathy (GSE)), caused by an abnormal immune reaction to partially digested gliadin, is the predominant disorder. Coeliac It probably occurs with comparable frequencies among all wheat-eating populations in the world. ^[20] Certain allergies and neuropathies are also caused by gluten consumption and inhalation. ^[21]

Note that wheat allergy and gluten intolerance are not the same thing. Wheat Allergy, also known as wheat hypersensitivity is most commonly a Food allergy, but can also be a respiratory or contact allergy resulting Coeliac ^[22]

See also

• Textured vegetable protein
• Zein
• Triticeae glutens

References

Further reading

• Curtis, B. C. ; Rajaram, S. & Macpherson, H. G. , Bread Wheat, Improvement and production — FAO Plant Production and Protection Series No. #30., <http://www.fao.org/DOCREP/006/Y4011E/y4011e05.htm>. Retrieved on 21 August 2007 
• Pfluger, Laura, Marker Assisted Selection in Wheat, Quality traits. Gluten Strength, Coordinated Agricultural Project (funded by USDACREES), <http://maswheat.ucdavis.edu/protocols/gluten/index.htm>. Retrieved on 29 September 2007 
• Agricultural Databases, Statistics, etc., USDA Cereal Disease Laboratory, <http://www.ars.usda.gov/Main/docs.htm?docid=11017> 
• Wieser, H. (2007), Cereal Chemistry and Dough Properties, KL1-Gluten Chemistry, <http://fp.cerealsandeurope.net/events/sourdough/session1.htm>. Retrieved on 27 September 2007 
• Wrigley, C. W; Bekes, F. & Bushuk, W (2006), The Gluten Composition of Wheat Varieties and Genotypes, AACC International, ISBN 1-891127-51-9, <http://aaccnet.org/grainbin/gluten_gliadin.asp>. Retrieved on 21 September 2007