CAN SEED PROTEIN QUALITY BE MANIPULATED?
Vegetable, notably soybean, proteins have been used in the food industry for many years and their beneficial effects are attributed to their so-called “functional” properties, particularly those that relate to gelation, emulsifying, and foaming behavior. Few studies have been carried out on engineering the properties of legume globulins to alter functional behavior, but those of Utsumi’s group (Maruyama et al., 2002; Utsumi et al., 2002) have given valuable insights into the relationship between structure and functionality for soybean proteins. The lack of Cys and Met in legume seed globulins can readily be overcome in feed production by mixing with cereal protein (which has a complementary composition; Shewry and Tatham, 1999), but is still regarded as a target for improvement (Krishnan, 2000). Legume proteins are especially poor for ruminant nutrition, however, because the protein is degraded in the rumen. Processing using heat treatments may be helpful in improving nitrogen values f
