传统酸面团中优势乳酸菌的分离及性能研究

以自然发酵的传统酸面团为研究对象,对其中的优势乳酸菌进行分离及鉴定,并评价其产酸性能。结果表明:共筛选到7株乳酸菌,经形态学及16S rDNA序列分析鉴定为面包乳杆菌1株、短乳杆菌1株、植物乳杆菌3株、白面粉乳杆菌2株;供试乳酸菌的产酸能力具有菌种及菌株特异性,其中植物乳杆菌L2-2产酸能力最强,37℃发酵24 h发酵液pH值可达3.81。

Isolation and Properties of the Predominant Lactic Acid Bacteria from Traditional Sourdough

Traditional sourdough contains a large number of lactic acid bacteria. This paper aims to isolate and identify the predominant lactic acid bacteria in traditional natural fermented sourdough, and evaluate its acid-producing ability. A total of 7 lactic acid bacteria were screened through the MRS agar medium supplemented CaCO₃, Gram stain and catalase test. These tested strains were identified as 1 strain of Lactobacillus crustorum, 1 strain of Lactobacillus brevis, 3 strains of Lactobacillus plantarum, 2 strains of Lactobacillus siliginis by the morphological properties and analysis of the 16S rDNA gene sequences. The pH value of the fermentation broth was significantly different after the seven strain of lactic acid bacteria cultured at 37°C for 24 hours, and their acid-producing ability was specific to species and strains. Among them, Lactobacillus plantarum L2-2 showed the strongest ability to produce acid, which the pH value of the fermentation broth reached to the pH 3.81 after 24 hours of fermentation at 37°C.