湘西酸肉中降解亚硝酸盐菌种的筛选与鉴定

Screening and Identification of Nitrite-Degrading Strains in Xiangxi Sour Meat

为从湘西酸肉中分离筛选出可高效降解并耐受高浓度亚硝酸盐的菌株,以自制酸肉为原料,使用稀释涂布平板法、平板划线法分离纯化菌株,通过盐酸萘乙二胺法进行指标检测,得到了4株可明显降解亚硝酸盐的菌株,经过形态学和分子生物学鉴定,确认菌1和菌2为异常威克汉姆酵母(Wickerhamomyces anomalus),菌3和菌4为清酒乳酸杆菌(Latilactobacillus sakei)。通过发酵条件的优化和耐受能力的测定,证明了从湘西酸肉中筛选出的1号菌株,对高浓度(500 mg/L)的亚硝酸盐具有较强的降解和耐受能力,在接种量为4%,p H值为4时,对亚硝酸盐的降解率最高可达82.74%。该研究筛选的酵母菌和乳酸菌对人体无害,可投入到发酵肉制品的生产中,具有较高的应用价值。

This experiment aims from Xiangxi sour meat(fermented meat products)to isolate and screen out strains that can efficiently degrade and tolerate high concentrations of nitrite.Using self-made sour meat as raw material,the target strains were isolated and purified by the dilution coating plate method and plate streaking method;furthermore,by the N-(1-naphtyl)-ethylenediamine dihydrochloride spectrophotometric method,four strains that obviously degrated nitrite were determined.The morphological and molecular biological identification confirmed that strains 1 and 2 were Wickerhamomyces anomalus,and strains 3 and 4 were Latilactobacillus sakei.Through the optimization of fermentation conditions and the determination of tolerance,it was proved that strain 1 had strong degradability and tolerance to a high concentration(500 mg/L)of nitrite;when the inoculation amount was 4%and pH value was 4,its highest degradation rate for nitrite was 82.74%.The obtained yeast strain and lactobacilus strain in our experiment are harmless to human body and can be used as food starters in the production of fermented meat products,providing important use value for humans.