四川传统发酵肉中乳酸菌的分离及发酵特性研究

对四川传统发酵肉中乳酸菌进行分离鉴定,并对其发酵特性进行研究。以四川腊肉为研究对象,采用平板划线法对乳酸菌进行分离纯化,利用16S r DNA的序列测定技术对其鉴定,并对分离菌株在不同温度、p H、Na Cl浓度、亚硝酸盐浓度条件下的生长代谢、产酸能力进行研究,并对发酵产物中游离氨基酸进行测定分析。结果表明:筛选出的一株优势乳酸菌经分子生物学鉴定为戊糖片球菌(Pediococcus pentosaceus)。分离菌株对数生长期为6~18 h;最适发酵温度30℃,发酵p H5.5;对Na Cl及Na NO2耐受能力分别高达10%和150 mg/L;其代谢产物中共测出16种游离氨基酸,共包含5种人体必需氨基酸。 

Study on the isolation of lactic acid bacteria from Sichuan traditional fermented meat and its fermentation characteristics

The dominant lactic acid bacteria was isolated and identified from Sichuan traditional fermented meat products and its fermentation characteristics were investigated.Using Sichuan Bacon as the research object,lactic acid bacteria were isolated and purified by plate marking method,and it was identified by 16 S r DNA sequencing technique. Its growth metabolism and acid production capacity on the different temperature,p H,Na Cl concentration,nitrite concentration and fermentation products of amino acid were researched. The results showed that the dominant lactic acid bacteria was screened and identified Pediococcus pentosaceus. The logarithmic growth phase of strain was 6~18 h,the optimum fermentation temperature was 30 ℃,fermentation p H was 5.5,the strain also had good endurance abilities to the salt concentration 10% and the nitrite content 150 mg / L,and it could release 16 kinds of free amino acids,including 5 kinds of essential amino acids.