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目的 了解新乡市规模化奶牛养殖场生乳中菌落总数、金黄色葡萄球菌和卢-内酰胺酶的基线数据,为生乳安全性风险评估及国家标准更新提供资料.方法 以新乡市3家规模化奶牛养殖场(A、B、C场)为观测基地,2016年5月-2017年4月每月采集2家生乳样品各29份和1份混合样品.分别按照GB 4789.2-2010《食品安全国家标准食品微生物学检验菌落总数测定》和GB 4789.10-2010《食品安全国家标准食品微生物学检验金黄色葡萄球菌检验》测定菌落总数和金黄色葡萄球菌,胶体金法测卢-内酰胺酶残留.结果 3家奶牛养殖场单份样品菌落总数的中位数分别为13 000、4 450、130 000 CFU/ml,明显低于GB 19301-2010《食品安全国家标准生乳》中的限量(2×106 CFU/ml),差异有统计学意义(P＜0.01),3家奶牛养殖场的菌落总数之间差异有统计学意义(P＜0.05).各奶牛养殖场单份样品的菌落总数与混合样品比较,仅B场差异有统计学意义(P＜0.05).7～8月菌落总数较高.3家奶牛养殖场样品中金黄色葡萄球菌检出率分别为1.1％ (4/360)、16.7％(30/180)和0.0％(0/180),计数结果为50 ～ 42 000 CFU/ml.3家奶牛养殖场的所有样品中均检出β-内酰胺酶,检出率为6.1％～10.6％.结论 GB 19301-2010生乳菌落总数限量远高于新乡市实际情况,建议修订标准;个别奶牛养殖场生乳中存在一定程度的金黄色葡萄球菌污染,需加强监管;筛查出的β-内酰胺酶需进一步鉴定其来源,同时要加强对卢-内酰胺酶检测方法的研究.“,”Objective To investigate the current situation of aerobic plate count,Staphylococcus aureus and β-lactamas in raw milk in Xinxiang.Methods Twenty-nine samples and 1 mixed sample of raw milk from 2 of 3 large-scale diary farms were separately collected once a month lasting for a year.The aerobic plate count and S.aureus were determined according to the current national food safety standard,meanwhile β-lactamas was identified by colloidal gold method.Results The median of aerobic plate count (CFU/ml) of raw milk from 3 farms was 13 000,4 450 and 130 000 respectively,all significantly lower than the limit of 2 × 106CFU/ml in GB 19301-2010 (P ＜ 0.01).Significant difference existed between the 3 farms (P ＜ 0.05).When comparing with the mixed sample,the significant difference was only found in one farm (P ＜ 0.05).The aerobic plate count changed seasonally which was higher in July and August.S.aureus contamination rates of the 3 farms were 1.1％ (4/360),16.7％ (30/180) and 0.0％ (0/180),respectively,with the range of 50-42 000 CFU/ml.β-lactamas could be detected in raw milk from all three farms,and the positive rate was 6.1％-10.6％.Conclusion The limit of aerobic plate count of raw milk in GB 19301-2010 was much higher than the actual level in Xinxiang.It is recommended to revise the standard limit value.There was a certain degree of S.aureus contamination in raw milk in one of the farms,and supervision should be strengthened.Furthermore,identification of the source of β-lactamas was needed,the research on the detection method of β-lactamase should also be strengthened.