Study On Processing Of Germinated Soybean Accumulating Peptides And Its Soybean Milk

In this paper, specific soybeans as raw materials were germinated in dish. Effects of culture conditions and components of the culture solution on peptides accumulation during germination of soybean were investigated. In addition, the optimized processe parameters were carried out. The peptide-enriched soybean milk was developed. The main freults were summarized as follows:1. The optimization of germinating conditions, namely pH value, germination time and temperature, were conducted using response surface methodology with three variables and three levels. Results showed that culture conditions significantly affect the peptides content of germinated soybean. Box-Behnken experimental design showed that the optimal conditions for peptides accumulation in germinated soybean were at a temperature of 29.0℃, and a germinating time of 6 d, using CBS (5 mmol/L, pH 5.2) as culture solution. The maximum peptides content of germinated soybean was 159.38 mg/g DW under the optimized culture conditions, which increased 3.83-fold as compared with the ungerminated soybean.2. Among ten variables investigated with Plackett-Burman design, gibberellic acid, CaCl2, AlC13 and MnSO4 were selected based on their statistically significant (P<0.05) and positive effects on peptides content in germinated soybean. Subsequently, Box-Behnken design was used for further optimization of these variables to improve peptides content. The optimum concentrations were as follows:61.00μmol/L,11.20 mmol/L,10.13 mmol/L and12.17 mmol/L, respectively. An overall 2.10-fold increase in peptides accumulation was achieved in the optimized culture solution (162.57 mg/g) compared with control (77.37 mg/g), and 3.97-fold increase compared with ungerminated soybean (40.96 mg/g).3. After germination under the optimized culture conditions, then the germinated soybean was made into a kind of peptide-enriched soybean milk. Organoleptic assessment was carried out with fuzzy comprehensive evaluation methodology. Results showed that the basic ingredients of peptide-enriched soybean milk were:volumetric milk,8% sugar and0.2 % salt. The soybean milk was emulsioned with 0.06% monoglycerides and 0.04% sucrose ester. The prescription of peptide-enriched soybean milk were:0.3% CMC,0.2% PGA and 0.1% xanthan. No deposition was observed in the beverage after 2 months storage at room temperature. Fuzzy comprehensive evaluation methodology showed that peptide-enriched soybean milk was acceptable to sensory test members.