固态食醋自然发酵醋醅中生淀粉酶产生菌的筛选及初步应用

Screening and Preliminary Application of Raw Amylase-Producing Bacteria in Fermented Grains by Natural Fermentation of Solid-State Vinegar

从自然发酵固态醋醋醅样本中筛选并鉴定获得能同时产生淀粉酶、蛋白酶的菌株16株,在酸性条件下均有不同程度的生长与产酶性能。其中,中村芽孢杆菌(Bacillus nakamurai)k11在pH 3.0的酸性条件下能生长且能保存80%以上的酶活,用LB培养基培养48 h后,乙偶姻含量为47.71 mg/L。在固态食醋发酵初期接种中村芽孢杆菌k11,所得食醋的总酸、氨氮、不挥发酸含量等均有明显提高。通过3轮重复应用实验,可知食醋出醋率分别提高5.40%、5.05%及8.40%,所得食醋乳酸、苹果酸占比提升,草酸含量降低,游离氨基酸总量提升了71.52%,且半胱氨酸明显提升,食醋中醇类、酯类、酮类、吡嗪类、酚类物质的含量均有明显提升。研究结果表明,将中村芽孢杆菌应用到固态食醋发酵过程中,可提高出醋率,降低生产成本,并在一定程度上提升食醋的口感,对于提升传统发酵调味品的生产效率及产品品质具有重要意义。

Sixteen strains that can produce amylase and protease simultaneously are screened,identified and obtained from the samples of naturally fermented solid-state vinegar grains.They all have different degrees of growth and enzyme production performances under acidic conditions.Among them,Bacillus nakamurai k11 can grow under the acidic condition of pH 3.0 and preserve more than 80%of the enzyme activity.After 48 hours of cultivation with LB culture medium,the content of acetoin is 47.71 mg/L.In the early stage of solid-state vinegar fermentation,inoculation with Bacillus nakamurai k11 significantly increases the total acid,ammonia nitrogen and non-volatile acid content of the obtained vinegar.Through three rounds of repeated application experiments,it can be seen that the vinegar yield increases by 5.40%,5.05%and 8.40%respectively,the proportion of lactic acid and malic acid in the obtained vinegar increases,the content of oxalic acid decreases,the total amount of free amino acids increases by 71.52%,cysteine significantly increases,and the content of alcohols,esters,ketones,pyrazines and phenols in vinegar all significantly increases.The research results indicate that the application of Bacillus nakamurai in the solid-state vinegar fermentation process can improve the yield of vinegar,reduce production costs,and to some extent enhance the taste of vinegar,which is of great significance for improving the production efficiency and product quality of traditional fermented seasonings.