Sessions

Institutional catering is a field of outstanding importance in terms of food safety, providing meals to more than one million consumers nationwide every day, including children and the elderly. The microbiological cleanliness of food-contact surfaces plays a key role in the safe preparation and transport of meals. Contamination of these surfaces may contribute to the cross-contamination of ready-to-eat foods, posing a serious risk to consumers. The aim of this study was to investigate the occurrence of Escherichia coli in samples taken from the surfaces of food transport containers delivered from central kitchens to public educational institutions in Budapest, and to assess the associated food safety risks. Between September 2024 and March 2025, a total of 466 surface samples were collected from food transport containers in 17 institutions supplied by three central kitchens. Samples were taken using sterile swab methods and processed according to ISO 16649-2:2005, cultivated on TBX agar and identified through chromogenic reactions. Of all samples, 29% (135/466) tested positive for E. coli. Institutional positivity rates ranged from 0% to 83%, with six institutions showing above-average levels of contamination. Significant differences were observed between suppliers: supplier “A” showed 40% positivity, supplier “B” 15%, while supplier “C” showed 0%. Statistical analysis confirmed that both the institution (χ²=87.791; p<0.001) and the supplier (χ²=47.384; p<0.001) significantly influenced the results, with institutional factors exerting a stronger impact. The results indicated that the silicone seals of food transport containers represent a critical food safety risk factor. The 29% positivity rate observed in this study demonstrates that current cleaning and disinfection procedures are not consistently effective in ensuring microbiological safety, thereby sustaining the risk of cross-contamination. Statistical analyses revealed that both institutional hygiene practices and suppliers influenced contamination levels; however, differences between institutions had a stronger effect. This highlights that local operational protocols, staff compliance with hygiene standards, and environmental cleanliness are more decisive factors than supplier-related variations alone. In conclusion, the findings emphasize the essential role of regular microbiological monitoring of critical surfaces, targeted hygiene training for food handlers, and the consistent, institution-level implementation of HACCP principles in reducing food safety risks in public catering.