Hygiene assessments of school kitchens based on the microbiological status of served food.

Background: According to European trends, more children eat at school canteens than ever before, therefore food safety and quality have become increasingly significant in recent years. Nevertheless, there are large differences in food safety levels in different school canteens. We hypothesize that the microbial status of the served meal represents on the general hygiene of the kitchen. Our research examines whether mesophilic aerobic bacteria measured in served food are connected with the level of hygiene in the catering unit, and whether this indicator can be used as a criterion for assessing school kitchens.

Methods: Meal samples were collected from six school kitchens, and mesophilic aerobic bacterial count was measured. Samples were collected on five different days, so each kitchen was monitored five times. Two meals per visit were collected: a soup and a main course.

Results: Out of the 60 samples, 26 were good (CFU/g < 103), 24 were acceptable (CFU/g: 103–105), and in 10 samples, the microbial count was found to be above the limit (CFU/g > 105). Statistical calculations revealed that microbial contamination of served meals was influenced neither by the supplier nor by the type of meal (soup or main course). However, the level of hygiene in the serving kitchen significantly affects the microbial status of meals.

Conclusions: Based on the results, a qualification system can be developed using the mesophilic aerobic bacterial count measurable in the served meal to assess hygiene. By regular determination of mesophilic aerobic bacterial count and the presence of Enterobacteriaceae, the food safety of a catering unit can be quantitatively evaluated.