Contamination status of Listeria monocytogenesin the production process of frozen drinks
WANG Lan, JIA Hua-yun, CHEN Shuai, LIU Xiao-ge, LIU Jian-qi, ZHANG Lin-qing, ZHANG Hong, ZHAN Zhi-fei
Key Laboratory of Microbial Molecular Biology of Hunan Province, Hunan Provincial Center for Disease Control and Prevention, Changsha, Hunan 410005, China
Abstract:Objective To investigate the contamination status of Listeria monocytogenes (hereinafter referred to as L. monocytogenes) in the production process of frozen drinks in Hunan Province so as to provide scientific evidence for prevention and control of foodborne diseases. Methods Seventy-five food samples from food material, intermediate and end products and 279 non-food samples from production environment, equipment, staff and tools were collected from each production process in 2 frozen drink manufactures in Hunan Province. L. monocytogenes was identified in accordance with the test methods specified in GB 4789.30-2010. And pulsed-field gel electrophoresis (PFGE) was used for molecular typing of L. monocytogenes isolates. Results A total of 354 samples were monitored in the 2 manufactures, and 28 strains of L. monocytogenes were detected, with the detection rate being 7.91%. All the 28 strains were detected in the 279 non-food samples, with the detection rate being 10.04%, of which the detection rate of environment samples was the highest (16.07%), followed by the samples collected from the staff (6.35%), apparatuses (6.58%) and tools (10.00%). The detection rate of L. monocytogenes was higher in filling zones (12.20%) than in pretreatment (0.96%) and packing zones (4.44%) as well as higher in manufacture O than in manufacture P (13.94% vs. 4.39%, χ2=6.815, P=0.009). PFGE showed that 23 strains of L. monocytogenes isolated from the samples of manufacture O had 4 subtypes, and 82.6% shared the same subtype. 4 of the 5 strains isolated from the samples of manufacture P possessed the same subtype. Conclusions L. monocytogenes isolates are detected in the production process of the 2 frozen drink manufactures, especially detected in the samples collected from the ground and objects contacting with the ground in filling zones. L. monocytogenes isolates detected in the 2 frozen drink manufactures possess the dominant subtypes. Disinfection and supervision should be strengthened to prevent the potential risk of frozen drinks contaminated by L. monocytogenes.
王岚,贾华云,陈帅,刘晓革,刘建琪,张林青,张红,湛志飞. 冷冻饮品加工过程中单核细胞增生李斯特菌污染状况分析[J]. 实用预防医学, 2017, 24(11): 1289-1292.
WANG Lan, JIA Hua-yun, CHEN Shuai, LIU Xiao-ge, LIU Jian-qi, ZHANG Lin-qing, ZHANG Hong, ZHAN Zhi-fei. Contamination status of Listeria monocytogenesin the production process of frozen drinks. , 2017, 24(11): 1289-1292.