Preparation of Soybean Peptide from Soybean Meal by Solid-Stated Fermented with Binary Compound Strains

Taking Bacillus subtilis,Saccharomyces cerevisiae and Aspergillus niger strains as material,and soluble protein(including amino acids and small peptides) were extracted from soybean meal by solid-stated fermentation with binary compound strains.Meanwhile,the solid-stated fermentation conditions that including the combination of dual strains,strain ratio,substrate water content,inoculation concentration,fermentation time,and fermentation temperature were studied by single factor experiment,and the optimum fermentation conditions for the optimal compound strains had been researched by RSA method.The results showed that using Bacillus subtilis and Aspergillus niger compound strains,the content of soybean peptide was the highest.The optimum fermentation conditions were inoculum 27.95%,fermentation temperture 35.92℃,substrate water content 52.71%,strain ratio between Bacillus subtilis and Aspergillus niger was 2∶1,and fermentation time 48 hours.The soybean peptide volume was 8.73% in the optimum conditions.