Introduction

SOYBEAN is one of the most important legume crops, representing 52% of thetotal oilseed production worldwide (USDA, 1999). The United States accounted for 46% of the world’s production of soybeans and for 60% of the world trade market, making it the world leader in soybean production (USDA, 1999). Soybean yields high protein soy meal, concentrate, and isolate, which are inexpensive protein sources. The major use of soybean in the food industry is as a source of oil, while soy protein concentrate and isolate are readily available as co-products of the oil processing industry (Pszczola, 1998).