Study on production technology of aquaic feed oligo-peptide soybean meal

In order to improve the aquatic feed processing quality of hydrolyzed soybean meal, single factor experiment and orthogonal test design were used for optimization of the bi-enzymatic hydrolysis conditions to produce aquatic feed oligo-peptide soybean meal in this study. Based on the evaluation of the production of soybean oligopeptide, the optimum hydrolysis conditions were designated as substrate concentration of 80 g/L, the ratio of the two enzyme (Alcalase: Flavourzyme) of 2:1, protease amount of 3000 U/g, hydrolysis temperature of 61°C, pH 8.0 and reaction time of 7.5 h. Finally, a yield of soybean oligo-peptide of 38.16% and a DH of 22.69% were obtained. The resultant oligopeptide soybean product had a better processing quality with a greater affinity with -starch and a less leaching loss of product of (2.5±0.7)%. The viscoelasticity and leaching losses of oligo-peptide product were able to meet the processing requirement of aquatic feeds. The results showed that the yield of oligo-peptide was a better indication for controlling the process of soybean meal hydrolysis than the DH (degree of hydrolysis) to produce a high-quality aquatic feed oligo-peptide soybean meal.