Investigation And Analysis On Microbial Contamination Of Commercially Produced Cold Dish In Changchun From 2017 To 2019

Cold dishes are dishes that are popular in people's daily life.Because cold vegetables may be contaminated by microorganisms at any step of the production chain and lack of treatment to kill pathogenic bacteria,they have high risks of causing foodborne diseases.Foodborne diseases are reported to spread widely around the world.However,there are few reports on the microbial contamination status of cold dishes in Changchun City.In order to evaluate the microbial contamination status of cold-selling vegetables in Changchun City,Jilin Province,the research work of this paper was carried out.This paper evaluates commercial microbial test strips based on standards such as the Evaluation Method for Commercialized Food Testing Kits.All test strips have good sensitivity,repeatability and specificity.In the initial screening stage,the LZ test piece was used to detect 69 cold dishes collected randomly.The qualified rate of the total number of colonies was 97.1%,and no pathogenic bacteria were detected.The results showed that:(1)The qualified rate of colonies in cold dishes was 89.3%.The pass rate of animal and mixed cold dishes reached 100%,and only the qualified rate of plant cold dishes was low(68%).(2)Only a few samples detected pathogenic bacteria,of which the detection rate of Escherichia coli was 2.2%;the detection rate of Staphylococcus aureus was 1.6%;the detection rate of Salmonella was 0.5%,animal And mixed cold dishes were not detected;the detection rate of Listeria monocytogenes was 1.5%,and plant and animal cold dishes were not detected.(3)The total number of colonies of all cold dishes in the supermarket did not exceed the standard,and the pass rate was 100%.Among them,the total qualified rate of colonies in the farmer's market(79.6%)was the lowest,and the pass rate of the total number of colonies in the food city(87.8%)was lower.(4)All pathogenic bacteria in the cold dishes in the supermarket were not detected;Salmonella in the cold dishes in the food city was not detected.The detection rate of Escherichia coli in cold dishes in the farmer's market is higher than other pathogenic bacteria.The results of this paper indicate that commercialized test strips can be used for testing in the early stages of food safety surveys,and the importance of strict environmental hygiene control in food processing is emphasized.The qualified rate of plant-based cold vegetables is low.When making plant-based cold dishes,it should be heat-treated to avoid the growth and reproduction of microorganisms.Relevant departments should strengthen supervision and citizens should raise awareness of food safety.