The soybean, or Glycine max, is a cultivated summer annual not found in the wild, and a member of the legume family. A staple food that is grown around the world, the plant has been labeled the world's most valuable bean. Asian cultures in particular have developed the use of soybeans. In fact, cultivation of the soybean probably began in China before recorded history. There it was revered as a healing and purifying agent and counted among the five sacred grains alongside rice, wheat, millet, and barley. Many foods are created by soaking, cooking, grinding, creaming, aging, and extruding the soybean. The Japanese, for example, use soybeans as the base of shoyu or soy sauce to flavor meat and vegetables. The salty, aromatic liquid is made from fermented soy paste and cereal. A similar emulsion, miso, combines soybeans and rice for a soy paste essential in...