Studies on protein quality of green gram (Phaseolus aureus)

Raw green gram contains trypsin inhibitor (5.6 x 10(-3) units/0.1 g) while cooking destroyed the trypsin inhibitor in green gram. No destruction was observed in the case of lysine, methionine, cystine, threonine and tryptophan. Sulphur containing amino acids have been found to be the only limiting amino acids in green gram from studies on blood levels of amino acids and PER experiments. Raw green gram, when fed as a sole source of protein promoted an extremely low growth rate, (13.2 g/4 weeks) and PER (0.77) in rats. Cooking slightly improved the nutritive value of the gram, as indicated by increase in gain in body weight (24 g/4 weeks) as well as PER (1.22). The presence of inhibitors in green gram did not appear to affect some of the essential amino acids as observed from the blood amino acid levels.