以哈尔滨周边地区不同养殖规模奶牛场为研究对象，针对春、夏季牛舍空气中微生物数量、菌群结构及原料乳中微生物种类进行检测和分析，以探讨奶牛饲养环境对原料乳品质及安全性的影响。本研究使用国产安德森六级空气微生物采样器采样，将样本在37 ℃时培养48 h后计数、分离、纯化，以基质辅助激光解析飞行时间质谱对纯化的菌株进行鉴定。结果表明，相同牛舍不同季节微生物含量有显著性差异（p<0.05），不同牛舍封闭季节空气中微生物含量差异性不显著（p>0.05）；A、C两牛舍敞开季节空气中微生物含量无显著性差异（p>0.05），而与B牛舍存在显著性差异（p<0.05）。牛舍空气中共鉴定出细菌116株，其中葡萄球菌属占32.76%，芽孢杆菌属占45.69%；原料乳中鉴定出细菌56株，其中乳酸菌占41.07%、肠杆菌占30.06%、葡萄球菌属占12.50%，且牛舍空气中与原料乳中微生物同源性较不明显。

Dairy farms of different scales in the surrounding area of Harbin were selected as the study objects, and the number of microorganisms and flora composition in cow shelters and the microbial species present in raw milk were determined and analyzed in both spring and summer. The aim of this study was to explore the effects of the breeding environment on the quality and safety of raw milk. The Andersen six-stage sampler was employed to collect microorganism samples in the air, and the samples were cultured at 37 ℃ for 48 h, followed by counting, isolation, and purification. The isolated cultures were identified by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS). Results showed significant differences in microbial content in the same cow shelter between spring and summer (p<0.05). No significant differences were found in the microbial content among different cow shelters in the season during which the shelter was enclosed. In the season during which the cow shelter was open, there were no significant differences in microbial content between cow shelters A and C (p>0.05). However, both of these shelters were significantly different from cow shelter C in terms of microbial content (p<0.05). There were 116 strains of bacteria identified in the air of cow shelters, including 32.76% Staphylococcus spp. and 45.69% Bacillus spp.; there were 56 strains of bacteria identified in the raw milk, including 41.07% lactic acid bacteria, 30.06% Enterobacter spp., and 12.50% Staphylococcus spp. The homology between microorganisms in the air of cow shelters and those in the from raw milk was not significant.

国家2011计划“食品安全与营养协同创新中心”