Analysis of Microbial Contamination in Catering Utensils with Coliform Failure by MALDI-TOF MS
In order to understand the contamination situation of coliform bacteria in catering utensils and whether the contaminated catering utensils pose a risk of disease,the microbial species in catering utensils that failed in the coliform bacteria group project were identified.The positive cultures were transferred to eosin methylene blue agar plates for isolation,and matrix-assisted laser resolved ionization time-of-flight mass spectrometry(MALDI-TOF MS)was used to accurately identify the single colonies of 62 wild strains of microorganisms isolated from 28 batches of unqualified tableware,with the identification rate of 93.55%,which was in line with that of the automated microbial biochemistry identification instrument.It mainly identified 10 kinds of microorganisms,including Cronobacter sakazakii,Cronobacter malonate,Escherichia coli,Klebsiella pneumoniae,Klebsiella acidogenes,Citrobacter freundii,and Enterobacter cloacae,etc.Among them,the proportion of microorganisms with disease-causing risk reached 68.97%,while 26 out of 28 batches of unqualified catering utensils had disease-causing risk,accounting for 92.86%.MALDI-TOF MS technology can quickly and accurately identify different microorganisms present in catering utensils at the same time,and unqualified coliform bacteria in catering utensils pose a higher risk of disease.Therefore,it is necessary to strengthen the hygiene management and monitoring of catering utensils.