Wheat is a grass widely cultivated for its seed, a cereal grain which is a worldwide staple food.The many species of wheat together make up the genus Triticum; the most widely grown is common wheat (T. aestivum). Wheat is an important source of carbohydrates. Globally, it is the leading source of vegetal protein in human food, having a protein content of about 13%, which is relatively high compared to other major cereals but relatively low in protein quality for supplying essential amino acids. A component of wheat that is of particular importance to bread making is gluten, which is produced by the hydration of the proteins glutenin and gliadin and further manipulation of the dough.