Bread wheat (Triticum aestivum) produces one-seeded fruits, which are called grains or kernels. The pleasant flavor, long shelf-life and unique gluten forming characteristics of wheat products like pasta, noodles, bread, chapatti etc. make them very attractive among other cereals.
Quantity, composition (quality), type and viscoelastic properties of wheat gluten proteins are important for bread-making. Gluten comprises some 75% protein on a dry weight basis, with most of the remainder being starch and lipids. Their biological function is to provide carbon, nitrogen and energy sources for seed germination and seedling growth.
The two distinct groups of the gluten polymer that were classified reflected their solubility in 70% ethanol, namely glutenins and gliadins. The gliadins are single polypeptide chains and the glutenins are comprising polymers with subunits linked by disulphide bonds, is particularly important.
The wheat gluten proteins correspond to the major storage proteins that are deposited in the starchy endosperm cells of the developing grain. These form a continuous proteinaceous matrix in the cells of the mature dry grain and are brought together to form a continuous viscoelastic network when flour is mixed with water to form dough. Dough mixing requirement, rheological properties of optimally mixed dough and gas retention property of fermenting dough are determined by gluten proteins.
Wheat prolamins are the major storage proteins present in the starchy endosperm cells of the grain, where they are synthesized and deposited via the secretory system. Prolamins are high content of the amino acids, proline and glutamine.
The non-prolamin proteins; albumins and globulins of wheat, comprises 15-20% of total wheat flour proteins. Albumins are soluble in water and globulins are soluble in salts.
Wheat protein
