Orawan Keeratisuthisathorn. Nutritive value of protein in soybean residue fermented with Rhizopus oligosporus and Bacillus subtilis . Master's Degree(Food Chemistry ). Chulalongkorn University. Center of Academic Resources. : Chulalongkorn University, 1996.
Nutritive value of protein in soybean residue fermented with Rhizopus oligosporus and Bacillus subtilis
Abstract:
The nutritional value of soybean residue from soymilk processing was found to decrease. This experiment fermented the soybean residues and soybeans with Rhizopus oligosporus TISTR 3001 and Bacillus subtilis TISTR 1 to produce tempeh and tooa-nao, respectively. Then the nutritive value of protein in the raw and fermented products were analysed. It was found that the crude protein contents in soybean residue tempeh, soybean residue tooa-nao, soybean tempeh, and soybean tooa-nao were increase 2.40%, 1.65%, 2.55%, and 1.85%, respectively, Valine, tyrosine, and phenylalanine contents were found to increase 9% to 16% after soybean residue tempeh fermentation. The contents of alanine and phenylalanine in soybean tempeh increased 31% and 15%, respectively. In soybean residue tooa-nao, cystine content increased 11.2% but valine content decreased 13%. In soybean tooa-nao, the contents of valine and lysine increased 26% and 11%, respectively but arginine content decreased 15%. Amino acid scores of some essential amino acids in fermented products were increase. The protein digestibility of soybean residue tempeh was increase from 67.68% to 74.95% whereas that of soybean residue tooa-nao remained constant. We also found that protein digestibility of soybean tempeh and soybean tooa-nao increased from 59.65% to 68.18% and 66.92%, respectively. In addition, vitamins contents were also affected by the fermentation process. These results suggest that the nutritive value of protein in soybean residue was improved by the fermentation process.