Frederick F. Shih, U.S. Department of Agriculture-Agricultural Research Service, Southern Regional Research Center, New Orleans, Louisiana
RICE: Chemistry and Technology, Third Edition
Rice protein is an important source of nutrition and energy for 50% of the world's population, for whom rice has long been a staple diet. The protein content of rice, at approximately 7%, is relatively low compared with that of other cereal grains. However, because of the huge quantity of rice produced worldwide (approximately 400 million metric tons annually), the amount of rice protein potentially available is considerable. On the other hand, rice protein has a significant influence on the structural, functional, and nutritional properties of rice. It is a major factor in determining the texture (e.g., stickiness), pasting capacity, and sensory characteristics of rice. In recent years, rice protein has been recognized to be uniquely nutritious and hypoallergenic, which makes rice increasingly popular for use in foods all over the world.
Extensive research has been conducted on rice proteins because scientists recognize the importance of protein for the understanding and utilization of rice. However, only limited efforts have been made to keep up with and summarize the information on rice proteins in the literature. Earlier reviews on the subject include those of Houston (1972), Lasztity (1984), and Hamaker (1994). Of particular significance was the review by Juliano (1985) in the second edition of this book, a revision of his work (Juliano, 1972) in the first edition. A lot more research has been done since, particularly on the characterization of rice proteins, processing of rice protein products, and development of better-quality rice proteins. This chapter is an update of information in the literature on the chemistry and technology of rice proteins. It is an overview covering materials from sources old and new, but the emphasis is on studies reported since Juliano's review (Juliano, 1985).