Oat vary among oat varieties. Also, oats products are frequently cross-contaminated with other gluten-containing cereals during grain harvesting, transport, storage or processing. Pure oats contain less than 20 parts per million of gluten from wheat, barley, rye, or any of their hybrids. Use of pure oats in a gluten-free diet offers improved nutritional value from the rich content of oat protein, vitamins, minerals, fiber, and lipids, but remains controversial because a small proportion of people with celiac disease react to pure oats. Some cultivars of pure oat could be a safe part of a gluten-free diet, requiring knowledge of the oat
Wheat gluten (food) and chewiness of the final product. Very little is required, generally about 1 Tablespoon (15ml) per 2-3 cups (480-620 ml) of flour. The powdered form of wheat gluten (vital wheat gluten), is made by hydrating hard wheat flour to activate the gluten and then processing the hydrated mass to remove the starch, leaving only the gluten. The gluten is then dried and ground back into a powder. Seitan may be made from vital wheat gluten or from hard wheat flour (a.k.a. high-protein flour, high-gluten flour, or gluten flour). When seitan is made from vital wheat gluten, the powder is simply