原料乳中主要微生物和理化指标的季节性变化及与奶厅环境的关系

The Seasonal Changes of Chemical and Main Microbiological Composition in Raw Milk and It's Relation with Dairy Hall Environment

本研究的目的是分析奶牛场生产的原料乳中主要微生物及理化指标的季节性变化规律和影响因素。采集奶牛场的奶样及奶厅环境空气样品,在实验室检测原料乳中的主要微生物及理化指标,并进行对比,分析影响其指标的主要因素。检测结果表明,冬季牛乳的营养成分高于春、夏、秋三季,微生物各项指标优于春、夏、秋三季,而且未检测到沙门氏菌、蜡样芽孢杆菌和单增李斯特菌。奶厅环境空气中的细菌含量冬季最高,夏季最低。得出结论:原料乳的理化指标和微生物指标在不同季节间有较大差异,乳中细菌含量与奶厅环境空气中的细菌含量没有必然的关系,只要严格执行原料乳生产过程的卫生管理规范,就能有效控制和减少原料乳细菌总数和病原菌的数量,生产出安全合格的牛乳产品。

The objective of this study was to detect chemical and main microbiological composition in raw milk, and analyze its relation with dairy hall environment. By collecting the raw milk and air bacteria in the dairy hall, the chemical and main microbiological composition of raw milk in the lab were detected based on the obtained data. Result showed that the nutritional ingredient of raw milk in winter was higher than it in spring, summer and autumn. The component of raw milk in four seasons was higher than the standards for the qualifications of raw and fresh milk. Otherwise, Salmonella enterica, Bacillus cereus and increasing Listeria monocytogenes were not detected in the raw milk. So the quality of raw milk was acceptable although E.coli was present and required the establishment of relevant health quality standards. The concentration of airborne aerobic bacteria in dairy hall environment reached a summit in winter and bottom in summer. The chemical index of raw milk is affected by seasonal changes, but reached national standards for the acquisition. The number of microorganisms in raw milk and seasonality was not necessarily related. We should take stricting implementation of raw milk production process of health management norms, in order to effectively control and reduce the total number of raw milk bacteria and pathogenic bacteria, so safe and health milk products were produced.