唾液乳杆菌M18-6在发酵大豆蛋白体系中的应用

通过测定发酵豆乳的凝乳时间、贮藏期间的活菌数和对菌株自身耐受性评价,筛选出1株能够稳定快速发酵大豆蛋白体系的乳酸菌菌株。以最短凝乳时间和贮藏期菌株的高存活率为主要依据,筛选出凝乳时间短、活菌贮藏性稳定的1株唾液乳杆菌M18-6,并对发酵体系进行抗氧化性评价。结果表明:M18-6最佳凝乳时间为(2.50±0.20)h,24 d贮藏期内M18-6菌株活菌数始终保持在10^8 CFU/mL以上,在pH 2.0的酸性环境中,存活率高于3.16×10^8 CFU/mL;同时发现,M18-6发酵体系对DPPH自由基的清除率达到93.34%,显著高于未发酵体系(P<0.05)。筛选出的唾液乳杆菌M18-6凝乳时间短,具有良好的活菌贮藏稳定性和清除DPPH自由基的能力,为后期开发快速发酵大豆蛋白体系的益生菌菌株提供理论依据。

Application of Lactobacillus salivarius M18-6 in the fermentation of soybean protein

To screen a strain of Lactic Acid Bacteria for the fermentation of soybean protein based on the measurement of the curd time,the number of viable bacteria during storage and the ability of stress resistance.Based on the shortest curd time and the high survival rate of the strains during storage,a strain of Lactobacillus salivarius M18-6 with short curd time and stable storage of viable bacteria was selected.The antioxidant ability of the fermentation system was evaluated.The optimal curding time of M18-6 was(2.50±0.20)h.The viable count of M18-6 strain remained more than 10^8 CFU/mL during 24 day storage.At pH 2.0,the survival rate reached 3.16×10^8 CFU/mL.Meanwhile,it was found that the DPPH clearance rate of the fermentation system reached 93.34%,which significantly higher than that of the control system(P<0.05).The selected Lactobacillus salivarius M18-6 had a short curding time,good storage stability and excellent scavenge ability to DPPH free radicals.This study provided a theoretical basis for the development of probiotic strains for rapid fermentation of soybean protein system.