Gluten (from Latin gluten, "glue") is a group of proteins, called prolamins and glutelins, which occur with starch in the endosperm of various cereal grains. This protein complex supplies 75–85% of the total protein in bread wheat. It is found in related wheat species and hybrids, (such as spelt, khorasan, emmer, einkorn, and triticale), barley, rye, and oats, as well as products derived from these grains, such as breads and malts. (extracted from Wikipedia). In breadmaking, gluten is responsible for the texture of the bread, creating a structure for the air that is released during fermentation to be trapped inside of the dough, resulting in a fluffy product.