Study On Isolation And Identification And Characteristics Of Film-pruducing Strains In The Vinegar

10Bacillus were isolated from the vinegar in Hohhot Shenggu Brewing Co.then done some physiology biochemistry and molecular identification.The results indicate that:1,4,5,8and9Bacillus were identified as Bacillus subtilis,2and6Bacillus were identified as Bacillus megaterium,3,7and10Bacillus were identified as Bacillus licheniformis.1,2,3Bacillus and Bacillus cereus were done some tolerance test. The results show that:four kinds of Bacillus grow strong in40℃, pH=6,2%NaCl, and the growth was obviously inhibited in100℃, pH=2,12%NaCl.1,2,3Bacillus and Bacillus cereus were done some antibacterial test. The results show that:the antibacterial effects of sodium benzoate and Nisin is best, followed by s-poly-lysine, and finally is the Nebo Golden ester. But the minimum inhibitory concentration of sodium benzoate has exceeded the maximum amount allowed in food. So in the extent permitted in the food, the inhibition of sodium benzoate is very small.Nisin, ε-poly-lysine and NaCl as the main factors, the number of bacterial as the indicator, do the orthogonal experiment. The results show that:Nisin plays the main role on the inhibition of Bacillus, followed by ε-poly-lysine and NaCl, the best antibacterial combinations is:A3B3C2, the dosage of Nisin is3mg/mL, the dosage of s-poly-lysine is3mg/mL, the concentration of NaCl is3%.The variance analysis shows that factor A very significant, factor B significant and factor C is not significant. Nisin (A) and ε-poly-lysine (B) has significantly impact the test. Therefore the test conditions is not freely select in actual production. The concentration of NaCl did not significantly influence the test, so we can select the test conditions by vinegar flavor in the production.