Soybean flour is often added to cereal flour and is used extensively in the baking industry. The majority of breads contain some soy flour. Pastries, cakes, biscuits, and baby foods may contain soy flour. Fermented soybean may be used in the preparation of soy sauce or Worcestershire sauce. Fermented soy is in wide use as a food in the Far East.
Soy is so widely distributed in processed foods that avoidance of soy in the diet is very difficult.
For example, if margarine is added to a food product it will be listed as such, but soy present in the margarine itself will not be listed on the ingredients panel. The concentrate or isolate may also be used in soy milk and as a protein concentrate added to health foods and high-protein biscuits. Soy may be converted into products having a meat-like texture. These products are often used as meat substitutes in vegetarian products and in catering establishments, including hospital and army food services, and feeding programs. The seeds of soybeans are widely used as a source of oil.