传统发酵食品中耐胃肠道环境乳酸菌的筛选及其在酸乳发酵中的应用

Screening of lactic acid bacteria strains with resistance to gastrointestinal environment isolated from traditional foods and their application in fermented yoghurt

在前期从民族传统发酵食品中分离得到的乳酸菌中,通过检测在人工胃肠道溶液中存活率筛选胃肠道环境耐受性强的菌株,再通过感官评价、质构测定等对耐受性强的菌株应用于酸乳发酵潜力进行综合性评价。结果显示,58株从民族地区传统食品中分离的乳酸菌中有7株菌于4种人工胃肠道溶液中存活率均在50%以上,其中5株菌的发酵酸乳感官评价得分较高;而菌株"新E6"发酵的酸乳在质构破裂力、最大黏附力、硬度、内聚力、弹性、胶黏性、咀嚼性以及黏度、持水力等指标都较优,分子生物学鉴定结果"新E6"为坚强肠球菌(Enterococcus durans),为后续益生菌的开发奠定基础。

Starter agents used in yogurt production are mostly good fermentation lactic acid bacteria,but not probiotics strains.As probiotics strains,lactic acid bacteria must go through gastrointestinal environment,and adhere and colonize in the intestinal tract.In this paper,the highly tolerant lactic acid bacteria strains isolated from the ethnic traditional food were screened by detecting the survival rate of strains in the artificial gastrointestinal solution.Then their potential application on yogurt was also comprehensively assessed by sensory evaluation and texture analyzer.The results showed that survival rate of 7 strains among 58 lactic acid bacteria strains were more than 50%in the 4 kinds of artificial gastrointestinal solution,wherein the score of sensory evaluation of 5 strains were higher.The yoghourt fermented with strain"Xin E6"was outstanding on texture rupture force,the maximum adhesion force,hardness,cohesiveness,elasticity,tackiness,chewiness,viscosity,and holding water capacity.The"Xin E6"was identified to be Enterococcus durans by molecular biology methods."Xin E6"showed application potential in the development of probiotics starter agent.