Corn gluten, a by-product of the starch industry, is a quality product with a high protein ratio, obtained by separating the corn by physical methods as a result of wet processing. It is the remaining part of the corn grain after the starch of the endosperm, except the bran and the embryo (corn germ), is removed. Corn gluten is a valuable methionine source and also contains a high proportion of xanthophylls. It is an extremely popular feed raw material in fish feeds due to its high amino acid content and absence of antinutritional factors, in broiler and chicken feeds due to its xanthophyll content, and in ruminant feding due to its high by-pass protein content. The protein content veries between 58% and 68%, although it varies according to the amount of other corn derivatives remaining in it.