Gluten contamination survey on school kitchen surfaces and identification of the food handling practices limiting cross-contamination with gluten

The demand for gluten-free meals is constantly increasing in school catering, but the serving process of gluten-free meals is less controlled. In this work, the presence of gluten was surveyed in school catering units to identify the food handling practices which effectively reduce gluten contamination. Thirty-nine school catering units were surveyed where gluten-free meals were regularly served. The presence of gluten was checked by immunochromatographic method on different kitchen surfaces. After the sampling, theoretical and practical training was held for food handlers and food handling practices were introduced to daily routine to better limit gluten cross-contamination on kitchen surfaces. The presence of gluten was re-checked after 1 month, and the food handling practice was checked with a checklist. Out of 156 sampled surfaces, 58 proved to be gluten-positive at the first sampling period, and only four kitchens were identified where all surfaces were gluten-negative. The most contaminated samples were microwave ovens (27 cases) and refrigerators (21 cases). During the second sampling period, the number of gluten-positive surfaces decreased to 28. Regarding the checklist, 18% of the surveyed kitchens were acceptable for all aspects. At the end of the intervention, 18 kitchens proved to be fully appropriate to serve gluten-free meals. It was found that the right cleaning processes show a higher correlation with the control of gluten cross-contamination. Since gluten may be present in school catering units, more emphasis should be placed on specific gluten controls in school kitchens. Thorough cleaning routines will largely contribute to the gluten-free environment. •Presence of gluten on school kitchen surfaces were surveyed.•Out of 156 kitchen surfaces, 58 proved to be gluten positive.•Microwave ovens and refrigerators are the most gluten-contaminated surfaces.•Gluten contamination can be decreased by appropriate food-handling practice.