Nutritional assessment of seed proteins in rice bean [Vigna umbellata (Thumb.) Ohwi and Ohashi].

Seeds of three rice bean accessions had 17.26 to 21.42% protein, 3.46 to 4.03% fat, 61.09 to 64.73% carbohydrates 3.99 to 4.58% ash and 5.22 to 7.43% fiber (dry weight basis). The most limiting amino acids in the seed meal, albumin and globulin fractions, were methionine and cysteine with chemical scores of these fractions being 38% to 59%. The amino acid pattern of globulin and seed meal were similar. The in vitro protein digestibility (IVPD) ranged from 82 to 86% for the seed meal, 86 to 88.5% for the albumin and 75.9 to 83.3% for the globulin. Relative nutritive values (RNV) of raw mature seed of two accessions were 22.6% and 42.4% and increased to 55.6% to 79.4% after boiling and roasting.