Monitoring of microbial contamination and molecular traceability analysis in the production of prepackaged cooked meat products

Objective To understand the microbial contamination during the production and processing of prepackaged cooked meat products in Henan, find out the high-risk links and key control points of contamination, reduce theprobability of food contamination, and incidence of foodborne diseases. Methods Sample collection and detection were performed according to the National Manual for Risk Monitoring of Food Contamination and Hazardous Factors, serotyping and molecular typing of positive strains were all performed according to the National Manual for Foodborne Disease Surveillance. Results A total of 168 samples were monitored, including 104 environment samples (4 in the raw area and 100 in the cooked area), 8 strains of Listeria monocytogenes were detected. A total of 24 strains of Listeria monocytogenes and 2 strains of Salmonella were detected from 60 cooked meat-related samples. 2 strains of Salmonella were Salmonella Enteritidis and had 2 molecular patterns with similarity of 92.9% by digestion with Xba Ⅰ and pulsed field gel electrophoresis. The 32 strains of Listeria monocytogenes were classified into six serotypes (1/2a, 1/2b, 1/2c, 4ab, 3a and 4b), and the dominant serotype was 1/2a.32 strains were divided into 17 molecular patterns by digestion with Asc Ⅰ and pulsed field gel electrophoresis, and each pattern contains 1-10 strains with similarity ranged 55.8%-100.0%. There were 4 water samples, and the total number of colonies and the coliform was all less than 1 CFU/mL, which met the requirements according to the national standard for drinking water. Conclusion There were common sources or cross-contamination in the environment and foods, microbial contamination could be effectively controlled after cooking, however, there were still deficiencies in other aspects. Therefore, it is suggested to further strengthen the management of product division, strengthen the disinfection treatment of ground and operators, and stipulate reasonable production processing and storage period