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Gluten (from Latin ''gluten'', "glue") is a mixture of proteins found in wheat and related grains, including barley and rye. Gluten gives elasticity to dough, helping it rise and keep its shape and often gives the final product a chewy texture. Gluten is the composite of two storage proteins, gliadin and a glutenin, and is conjoined with starch in the endosperm of various grass-related grains. Worldwide, gluten is a source of protein, both in foods prepared directly from sources containing it, and as an additive to foods otherwise low in protein. It is appreciated for its visco-elastic properties.〔 Gluten contains hundreds of proteins, which have low biological and nutritional value and high contents of prolamins (glutamines and prolines), as opposed to the grains of pseudocereals (gluten free), which are rich in proteins with high biological value (albumins and globulins).〔 The fruit of most flowering plants have endosperms with stored protein to nourish embryonic plants during germination. True gluten is limited to certain members of the grass family. The stored proteins of maize and rice are sometimes called glutens, but their proteins differ from true gluten. == Extraction == Gluten is extracted from flour by kneading the flour, agglomerating the gluten into an elastic network, a dough, and then washing out the starch. Starch granules disperse in cold/low-temperature water, and the dispersed starch is sedimented and dried. If a saline solution is used instead of water, a purer protein is obtained, with certain harmless impurities departing to the solution with the starch. Where starch is the prime product, cold water is the favored solvent because the impurities depart from the gluten. In home or restaurant cooking, a ball of wheat flour dough is kneaded under water until the starch disperses out. In industrial production, a slurry of wheat flour is kneaded vigorously by machinery until the gluten agglomerates into a mass. This mass is collected by centrifugation, then transported through several stages integrated in a continuous process.〔(【引用サイトリンク】 title=Wheat Starch and Wheat Gluten ) 〕 About 65% of the water in the wet gluten is removed by means of a screw press; the remainder is sprayed through an atomizer nozzle into a drying chamber, where it remains at an elevated temperature a short time to evaporate the water without denaturing the gluten. The process yields a flour-like powder with a 7% moisture content, which is air cooled and pneumatically transported to a receiving vessel. In the final step, the collected gluten is sifted and milled to produce a uniform product.〔(【引用サイトリンク】 title=Wheat )〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Gluten」の詳細全文を読む スポンサード リンク
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