家用冰箱冷藏室卫生现状调查及清洗效果评价

Hygiene status and cleaning effect evaluation of freezers in domestic refrigerators

目的调查居民家用冰箱冷藏室微生物污染状况,并评价专业冰箱清洗对冰箱内微生物污染的改善效果。方法在清洗前后,分别对成都市15台社区居民家用冰箱冷藏室的食物隔板、蔬菜框和门封条无菌采样,获得样品90份;检测样品细菌总数、真菌总数和大肠菌群以反映冰箱内卫生状况,同时进行大肠菌群、金黄色葡萄球菌、沙门菌、单核细胞增生李斯特菌和小肠结肠炎耶尔森氏菌的分离培养以反映致病菌污染状况;依据清洗前后微生物检出情况和清除率综合分析冰箱清洗效果。结果清洗前,冰箱内细菌总数范围为2.4×10^(3)~1.4×10^(5)CFU/cm^(2),清洗后细菌总数范围为0~230 CFU/cm^(2);食物隔板、蔬菜框和门封条的细菌清除率分别达到99.90%、99.89%、99.81%。清洗前,冰箱内真菌总数范围为0~750 CFU/cm^(2),清洗后真菌总数范围为0~58 CFU/cm^(2);食物隔板、蔬菜框和门封条的真菌清除率分别为99.40%、96.99%、99.41%。清洗前,冰箱冷藏室内大肠菌群平均检出率为64.44%,金黄色葡萄球菌平均检出率为13.33%,沙门菌平均检出率为2.22%,未检出单核细胞增生李斯特菌和小肠结肠炎耶尔森氏菌;清洗后,大肠菌群检出率为13.33%,均未检出金黄色葡萄球菌、沙门菌、单核细胞增生李斯特菌和小肠结肠炎耶尔森氏菌。结论本研究的家用冰箱冷藏室清洗前细菌和真菌数量较大,且存在金黄色葡萄球菌和沙门菌污染,专业清洗后冰箱卫生状况明显改善,极大地降低了食品安全隐患。

Objective To investigate the current status of microbial contamination in domestic freezers and evaluate the microbial improvement effects of professional refrigerator cleaning.Methods Samples were collected aseptically from the food dividers,vegetable frames,and door seals of 15 household refrigerators before and after cleaning in Chengdu City.A total of 90 samples were obtained.The total number of bacteria,fungi,and coliforms in the samples was determined to reflect the sanitary conditions of the refrigerator.Coliform bacteria,Staphylococcus aureus,Salmonella,Listeria monocytogenes and Yersinia enterocolitica were isolated and cultured to determine the contamination status of these pathogenic bacteria.The effect of refrigerator cleaning was analyzed comprehensively according to microorganism detection and clearance rates before and after cleaning.Results Before cleaning,the total number of bacteria in the refrigerator ranged from 2.4×10^(3)to 1.4×10^(5)CFU/cm^(2).After cleaning,the total number of bacteria ranged from 0 to 230 CFU/cm^(2).The bacterial clearance rates of the food dividers,vegetable frames,and door seals were 99.90%,99.89%,and 99.81%,respectively.Before cleaning,the total number of fungi in the refrigerator ranged from 0 to 750 CFU/cm^(2).After cleaning,the total number of fungi in the refrigerator ranged from 0 to 58 CFU/cm^(2).The fungal clearance rates for the partition,vegetable frame,and door seal were 99.40%,96.99%,and 99.41%,respectively.Before cleaning,the average detection rates of coliform bacteria,Staphylococcus aureus and Salmonella,were 64.44%,13.33%,and 2.22%,respectively;Listeria monocytogenes and Yersinia enterocolitica were not detected.After washing,the average coliform bacteria detection rate was 13.33%;Staphylococcus aureus,Salmonella,Listeria monocytogenes,and Yersinia enterocolitica were not detected.Conclusion This study revealed the presence of a high number of bacteria and fungi in the freezers of domestic refrigerators before cleaning,with S.aureus and Salmonella contamination.After professional cleaning,their sterility significantly improved,notably reducing potential food safety risks.