Abstract:

Objective To understand the contamination of Bacillus cereus in food sold in Wuxi City from 2012 to 2023，and provide scientific basis for the prevention and control of foodborne diseases. Methods According to the requirements of the "Annual Work Manual for Monitoring Food Microorganisms and Their Pathogenic Factors in Jiangsu Province"，727 samples of 10 types of food sold in 8 areas of Wuxi City were randomly collected.The Bacillus cereus was quantitatively detected according to GB4789.14-2014 "National Food Safety Standard-Food Microbiological Examination-Examination of Bacillus cereus"，and statistical analysis was conducted. Results Out of 727 sampled samples，77 were found to contain Bacillus cereus，with a total detection rate of 10.59%.The detection rate was highest in 2013（24.00%），followed by 2016（16.67%） and 2012（15.00%），with a statistically significant difference（χ²=33.027，P<0.05）. Among different types of food，the detection rate of student meals was the highest（16.83%），followed by infant cereal supplements（16.79%），cooked meat products（14.58%），and cooked rice and flour products（13.91%），with a statistically significant difference（χ²=41.874，P<0.05）. The difference in detection rate between bulk food（13.80%） and pre packaged food（7.98%） was statistically significant（χ²=6.440，P<0.05）. The detection rate was highest in the first quarter（33.33%），followed by the third quarter（12.70%），and the difference was statistically significant（χ²=26.691，P<0.05）. The quantitative detection results of Bacillus cereus showed that 57.14%（44/77） had colony counts below 10² CFU/g（mL），37.66%（29/77） had colony counts between 10²-<10⁵ CFU/g（mL），and 5.19%（4/77） had colony counts ≥10⁵ CFU/g（mL）. Among different sampling locations，the detection rate of roadside stalls was the highest（35.00%），followed by collective canteens （14.55%） and online stores（11.63%），and the difference was statistically significant（χ²=39.583，P<0.05）. Conclusion From 2012 to 2023，there was contamination of Bacillus cereus in various commercially available foods in Wuxi City. Special attention should be paid to the contamination of student meals and roadside stalls. Relevant departments should increase supervision，strengthen training and education，and prevent the occurrence of foodborne diseases.

Key words: Food safety, Bacillus cereus, Pollution monitoring, Microorganisms and their pathogenic factors, Foodborne diseases, Food sampling inspection