Microbial assessment in school foodservices and recommendations for food safety improvement

Abstract

This study evaluated microbial food safety in school foodservices. Five school foodservices were randomly selected, and samples from water, cooking utensils, tableware, foodservice surroundings, and linen were collected in summer and winter (N = 420). Tap and drinking water samples were collected, samples of food contact surfaces were collected by swab-kit, and samples for foodservice workers' hands and gloves were prepared by glove juice method. Aerobic plate count (APC) and coliform bacterial populations were enumerated on plate count agar (PCA) and desoxycholate lactose agar, respectively. The presence of Escherichia coli, Salmonella, Listeria monocytogenes, and Staphylococcus aureus was also examined by biochemical identification tests. In addition, PCA agar for APCs and Baird-Parker agar for S. aureus were used to enumerate airborne microorganisms. Higher APCs (< 0 to 5.1 log CFU/mL) than acceptable level were generally observed in water samples, while low coliform. counts were found in the samples. High APCs were enumerated in cooking utensils, foodservice workers, tableware, and foodservice surroundings, and coliforms were also found in the samples for both seasons. The presence of Salmonella was found from only 10% of plastic glove samples (summer), and the presence of L. monocytogeneswas not observed in all samples. S. aureus was detected in some of water, cooking utensils, tableware, employees, and foodservice surroundings, and E. coli was observed in cooking utensils (10% to 20%; summer). No obvious airborne bacteria were detected. These results showed that sanitation practice in school foodservices should be improved, and the results may be useful in microbial assessment of school foodservices.