Investigation on contamination status of Staphylococcus aureus from food and processing in Chengdu

Abstract

To understand the contamination status of Staphylococcus aureus in food and processing. From July 2017 to January 2018, raw/cooked meat products, aquatic products, soybean products and other foods for sale were collected from five districts and counties of Chengdu, and some processing samples were collected from school cantons, farms and slaughterhouses of Chengdu. Staphylococcus aureus in food and processing in Chengdu was detected by plate method and PCR method, staphylococcus aureus enterotoxin was determined by enzyme-linked fluorescence immunoassay, and Risk Ranger software was used for semi-quantitative Risk assessment. A total of 429 samples were collected from food and processing in Chengdu. 78 strains(18. 2%) of Staphylococcus aureus were detected by plate method, among which 76 strains were identified as Staphylococcus aureus by PCR. The highest detection rate was found in raw meat(34. 1%), and the highest detection rate was found in raw chicken(54. 2%). The detection rate of Staphylococcus aureus in samples from farmers' markets(34. 0%) was higher than that of supermarkets(28. 3%). Eighteen of the 78 strains produced enterotoxin, raw chicken and duck meat from supermarkets(9) and farmers' markets(6), and hand smears by school cafeteria workers(2). According to the risk score, the food safety risks are in descending order from raw meat products(55 points), soybean products(50 points), cooked meat products(43 points) and aquatic products(43 points). Raw meat and soybean products are high risk foods contaminated by S. aureus, cooked meat and aquatic products are medium risk foods.