功能性酸奶复合益生菌菌株筛选及发酵工艺优化OACSTPCD

Viscosity,acidity,texture,and sensory evaluation were selected as indicators,compound probiotics strains for functional yogurt were screened.Yogurt fermentation process was also optimized by response surface methodology.The yogurt quality under the optimal process was analyzed.The results showed that the optimal probiotics strains for functional yogurt were Lactobacillus plantarum Lp20265(Z02),Lactobacillus bulgaricus(Z05),Streptococcus thermophilus HST-9(Z07);the optimal fermentation conditions for the yogurt were as follows:strain ratio of Z02∶Z05∶Z07 was 2∶1∶2,walnut pulp content of 218 mL,fermentation temperature of 43.3℃,and fermentation time of 8.5 h.Under the above conditions,the yogurt had fatty acid(42.31±1.01)mg/g with 6 main components,protein content(324.9±1.01)mg/g,18 amino acids,6 organic acids,7 main aroma components,and coliform bacteria≤0.03 MPN/mL.No pathogenic bacteria or heavy metal lead was detected,which complied with the national food safety standards.This study provides technical reference for the development of functional yogurt.