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
Gluten vigorously to induce it to rise to its full capacity; an automatic bread machine or food processor may be required for high-gluten kneading. Generally, higher gluten levels are associated with higher overall protein content. Gluten, especially wheat gluten, is often the basis for imitation meats resembling beef, chicken, duck (see mock duck), fish and pork. When cooked in broth, gluten absorbs some of the surrounding liquid (including the flavor) and becomes firm to the bite. This use of gluten is a popular means of adding supplemental protein and variety to many vegetarian diets. Gluten is often present in beer and