Sessions

Institutional catering is a particularly sensitive area from a food safety perspective, as it provides daily meals for large groups of people, often including children and the elderly. They are especially vulnerable to foodborne illnesses, which makes the continuous monitoring of kitchen hygiene a critical task.

In this study, I analyzed microbiological data collected over a six-year period (2019–2024) from 96 school kitchens. A total of 8,412 surface samples were taken, covering both food-contact surfaces (FCS) and non-food-contact surfaces (NFCS). Hygiene was assessed on the basis of mesophilic aerobic colony counts (CFU/100 cm²), using 250 CFU/100 cm² as the threshold value.

Overall, 12% of the tested surfaces exceeded this limit. The most problematic sites were container lids used for food transport (67% above the threshold), sinks (33%), and workers’ hands (15%). These findings clearly point to shortcomings in cleaning routines and hand hygiene. By contrast, plates, glasses, and smaller kitchen tools showed much lower contamination rates (4–8%), suggesting that certain cleaning practices are more consistently effective.

Trends over time were mixed. Some kitchens showed moderate improvement across the study period, while others deteriorated. Differences between institutions were marked, highlighting the influence of local management and practices. Seasonal patterns were also evident. During the summer months, over 40% of surfaces exceeded the threshold, whereas contamination levels were significantly lower in winter, reflecting the impact of temperature and humidity on microbial growth. NFCS results were consistently worse across all seasons, indicating that these surfaces receive less systematic control.

The findings demonstrate that the mere presence of a HACCP system does not, in itself, guarantee hygienic safety. Effective protection requires strict adherence to cleaning and disinfection protocols, targeted surface monitoring, and regular staff training in hygiene practices. The study also shows that routine microbiological testing of critical points, supported by rapid methods (such as MicroTester), can be a valuable tool for assessing kitchen hygiene and identifying areas in need of intervention.

In conclusion, this research provides a comprehensive overview of hygiene conditions in institutional catering and offers an evidence-based foundation for food service managers and decision-makers to implement targeted improvements. The results underscore that ongoing monitoring, continuous training, and systematic control are indispensable for ensuring safe catering services.