Proteins of Plant Origin - Cereal Proteins
Cereal Proteins: Cereal grains, properly ripened and dried for optimum storage stability, have protein content ranging from 6-20%. Proteins are found in various morphological tissues of different grains. In the milling of grain (eg. wheat), the endosperm is essentially separated from the bran and germ and then pulverized to produce flour, which is used as food. Endosperm proteins apparently act as a structural component and also as food reserves for the growing seedlings. Much of the endosperm storage proteins in kernel of several cereal proteins are located in the sub-cellular granules or organelles known as 'protein bodies' (except in wheat kernel).
Bran or seed coat protein provides structure and protection to kernel. Since bran is so poorly digested by humans and the proteins are difficult to separate, most of the material is used for animal feed.