牛乳中细菌的检查

Inspection of Bacteria in the Milk

【目的】采用三种细菌学检查方法对牛乳中细菌进行卫生检查,比较得出最佳检测方法。【方法】采用显微镜计数法、美蓝还原酶实验法、标准平板计数法进行测定,确定不同来源的生牛乳的等级、巴氏消毒牛乳的卫生标准。【结果】微生物显微镜直接计数法随机性大,对菌体数量不能做出较为宏观,全面的反应.优点是计数快速;美蓝还原酶实验法是用于测定牛乳质量的一种定性检测法,操作简便,不需特别设备.它不能做为定量检查;平板菌落计数法速度慢,需要平板上长出菌落一段时后才能计数。【结论】由于平板菌落计数法通常间做梯度稀释,所以计数的线性范围大.由于是菌悬液涂布,所以比较均匀,能较好的反应菌落的疏密程度.重复性,平行性很好,是经典的计数方法。

[OBJECTIVE] Uses three bacteriological inspection method the bacteria to carry on the health inspection to the cow＇s milk in, compared with and obtains the best examination method. [METHOD] Uses the microscope count, the methylene blue reductase method, the standard plating count method to carry on the determination of the number of bacteria, determined different origin the fresh cow＇s milk rank, pasteurized milk hygienic standard. [RESULTS] Microorganism microscope direct count method has big randomness. It cannot make comparatively macroscopic, overall comprehensive for milk quantity. But the advantages are continuing and fast for counting of bacteria; The methylene blue reductases method is used in determining the cow＇s milk quality .It is simple.No special equipments needed.But it cannot use for the quantitative examination; The plating colony count methods is relatively slow, needs the growth of bacteria on the plate and colonies can be counted.[CONCLUSION] Because the plating count method usually makes the gradient to dilution, therefore the counting linear scope is broad. Because bacterium suspended solution is poured out on the culture of bacterium uniformly. The bacterial colony density degree can obtain. The retentiveness, parallelism is very good. It is the classical method of counting bacteria.