中温大曲中乳酸菌的分离鉴定及产酸特性

Isolation & Identification of Lactic Acid Bacteria in Medium-temperature Daqu & Its Acid-producing Properties

对宋河中温酒曲中的乳酸菌进行分离鉴定并研究产酸特性。共分离得到19株乳酸菌,初步鉴定了4个属8个种的16株乳酸菌,4个属分别为微球菌属、片球菌属、链球菌属和乳杆菌属,8个种分别为藤黄微球菌(M.Lu-teus)、皱褶微球菌(M.Colpogenes)、变异微球菌(M.Varians)、乳酸片球菌((P.Acidilactici)、戊糖片球菌(P.Pentosaceus)、乳链球菌(S.Lactis)、乳酸乳杆菌(L.Lactis)和短乳杆菌(L.Brevis)。微球菌和片球菌是宋河中温大曲中的优势乳酸菌。14株乳酸菌的产酸特性可分为两种类型:一类是乳酸菌在37℃发酵12 h时,pH值可达到最小值,此后逐渐上升;另一类是乳酸菌37℃发酵12 h,pH值迅速下降,24 h可达到最小值,此后逐渐趋于平缓。

19 lactic acid bacteria strains were isolated from Songhe medium-temperature Daqu. Among them, 16 strains were preliminarily classified into four genera including Micrococcus, Pedicoccus, Streptococcus and Lactobacillus, and 8 species including Micrococcus Luteus, Micrococcus Colpogenes, Micrococcus Varians, Pediococcus A cidilactici, Pediococcus Pentosaceus, Streptococcus Lactis, Lactobacillus Lactis, and Lactobacillus Brevis. The Micrococcus and Pediococcus were dominant lactic acid bacteria in medium-temperature Daqu. The acid-producing properties of 14 lactic acid bacteria strains could be divided into two types： Type one, pH value reached up to the minimum after 12 h fermentation at 37 ℃ and then decreased gradually; Type two, pH value decreased rapidly after 12 h fermentation at 37 ℃ and reached up to the minimum at 24 h and kept stable gradually after then.