传统发酵豆酱中乳酸菌的分离、筛选及鉴定

Isolation,Screening and Identification of Lactic Acid Bacteria from the Traditional Fermented Soybean Paste

在豆酱的自然发酵过程中,乳酸菌是促成豆酱风味物质形成的重要微生物。豆酱呈味主要是通过乳酸菌发酵糖类产生小分子醛、酸、酯等风味物质。以黑龙江发酵豆酱作为研究对象,对发酵过程中的乳酸菌进行传统的分离、培养、鉴定和筛选,并利用16S rDNA的序列测定技术,对乳酸菌群进行研究。从豆酱样品中共分离出有溶钙圈的菌株44株,其中过氧化氢试验阴性,同时革兰氏染色阳性的菌株共6株,初步鉴定为乳酸菌,将其分别命名为:HDBL-1,HDBL-2,HDBL-3,HDBL-4,HDBL-5,HDBL-6。同时,获得了1株产酸低且耐盐菌HDBL-7,对该菌株进行鉴定后,确定其为乳酸片球菌(Pediococcus acidilactici)。该研究为改善豆酱的品质和豆酱的工业化生产奠定了菌种来源基础。

Lactic acid bacteria play a leading role in the natural fermentation progress of soybean paste, they have heavy correlations to the flavor and the quality of the soybean paste. Lactic acid bacteria could produce small molecule aldehydes, acids, esters and so on by fermenting carbohydrate to the flavor of the soybean paste. In this study, we used the fermented soybean paste from Heilongjiang Province as material, analyzed lactic acid bacteria during the fermentation using the methods of traditional isolation, culture, screening, identification and 16S rDNA gene sequences technology. Through calcium-dissolving zone, we isolated 44 strains lactic acid bacteria from the samples. There are 6 strains named as： HDBL-1, HDBL-2, HDBL-3, HDBL-4, HDBL-5, HDBL-6, which were negative in hydrogen peroxide test, while were positive in Gram stain. Then the salt-tolerant with low lactic acid activity HDBL-7 was isolated and identified to be Pediococcus acidilactici. The research laid the foundation for the quality study and industrial production of soybean paste.