嗜冷菌对牛乳货架期的影响

Effect of psychroph on shelf life of milk

采用Azocasein法和碱式滴定法对嗜冷菌产蛋白酶和脂肪酶的活力进行了测定。研究了嗜冷菌在原料乳中的生长规律。结果表明,嗜冷菌产蛋白酶和脂肪酶的最佳pH值为7.0,最适培养温度在30℃,产酶高峰分别出现在30 h和24 h,在最适培养条件下嗜冷菌数的动态增加与蛋白酶和脂肪酶活力变化趋势大致相同。原料乳在低温贮藏过程中,嗜冷菌数与蛋白质、脂肪、水分、密度、pH值也存在有数学相关性。

In this study, Azocasein law and basic titration ofPsychrotroph protease production and the vitality of the lipase were determined. Research Psychrotroph in raw milk in the growth of the law, the results show that Psychrotroph protease and lipase yield the best pH value of 7.0, the optimum temperature at 30 ℃, the middle-peak appeared in 30 hours and 24 hours, In the best training conditions Psychrotroph increase in the number of dynamic and protease enzyme activity and fat or less the same trend. In the low-temperature storage of raw milk, Psychrotroph with the number of protein, fat, water content, density, pH value also mathematically related to each other.