戊糖片球菌NCU301对豆粕强化发酵工艺优化及营养成分的测定

研究戊糖片球菌NCU301对豆粕(未灭菌)强化发酵的最佳工艺条件,测定豆粕发酵前后营养成分和抗营养因子的变化。以乳酸菌活菌量为指标,通过单因素实验和Box-Behnken响应面分析法优化豆粕强化发酵工艺,确定最佳工艺条件为:发酵时间50.0 h、发酵温度30.0 ℃、料水比1:0.82、接种量8%,优化后活菌量达到1.15×1010 CFU/g。此外,测定豆粕发酵前后营养成分和抗营养因子变化。结果表明:与未发酵豆粕相比,强化发酵豆粕中粗蛋白、酸溶性蛋白、小肽、游离氨基酸的含量分别提高4.78%、36.04%、52.21%、19.10%,胰蛋白酶抑制剂活性和脲酶活性分别下降89.56%、91.72%;与自然发酵豆粕相比,粗蛋白、游离氨基酸总量分别提高0.6%、35.89%,酸溶性蛋白含量、小肽含量,胰蛋白酶抑制剂活性和脲酶活性分别下降4.64%、3.35%、72.79%、60%。使用戊糖片球菌作为豆粕发酵的菌种不仅可以作为抗生素替代品,还可以提高豆粕的营养价值。

Optimization of process and determine of nutrients of intensive fermentation of soybean meal by Pediococcus pentosaceus NCU301

In this study, process conditions of enhanced fermentation of soybean meal (non-sterilized) by Pediococcus pentosaceus NCU301 was optimized, and changes of nutrients and anti-nutritional factors in soybean meal were determined. According to the viable counts of lactic acid bacteria, optimum fermentation conditions were obtained through single factor experiment and response surface analysis of Box-Behnken. Results showed that the optimum fermentation time, temperature, and inoculum respectively were 50.0 h, 30.3℃, 8%, respectively, with the optimum ratio of material to water 1:0.82.Under these conditions, the viable bacteria amount of fermented soybean meal reach 1.15×1010 CFU/g. Moreover, the changes of nutrients and anti-nutritional factors before and after fermentation were determined. The results showed after enhanced fermentation, the content of crude protein, acid soluble protein, peptide and amino acids in soybean meal increased by 4.78%, 36.04%, 52.21%, 19.10%, respectively, while trypsin inhibitor activity and urease activity declined by 89.56% and 91.72%, comparing with soybean meal of unfermented. And the content of crude protein, and amino acids in soybean meal increased by 0.6%, 35.89%, while acid soluble protein, peptide, trypsin inhibitor activity and urease activity declined by 4.64%, 3.35%, 72.79% and 60%, comparing with soybean meal of natural fermented. Pediococcus pentosaceus as starter culture of soybean meal not only replaced of antibiotics, but also increased nutritive value of soybean meal.