Study on gluten cross-contamination in food preparation sites

This study was conducted in order to determine; level of gluten contamination in gluten-free foods and preparation site caused by cross-contamination while preparing wheat floured foods. Also, aims of this single-blind randomized study were to assess the optimum distance to prevent gluten contamination and relationship between distance of gluten-free foods from preparation site and between period of preparation of wheat floured foods and level of gluten contamination in gluten-free foods. Totaly 40 gluten-free petri dishes (4 samples in each distance and one meter high from the ground) were placed as uncovered at 0.5, 1.0, 2.0, 3.0 and 4.0 meters distances from the food preparation site containing wheat flour in two different directions. Three kinds of wheat floured pastries were prepared by a chef. After 0.5, 1,2 and 3 hours from preparation have started, one sample at each distance was collected respectively. In addition, glutenfree petri dishes were placed at next to the nearest bench to preparation site, scale, kitchen sink, stove, on the oven and samples were collected at end of preparing. Gluten contamination levels of the samples were determined by ELISA method. According to this study results, gluten contamination levels of the samples were below the legal gluten limits (<20 ppm). Gluten contamination levels of the samples were significantly different when compared to the control sample (p<0.05). Maximum gluten contamination levels were determined 0.5 meter distance from the preparation site and the contamination period was 1 hour. Although gluten contamination levels were below the legal limits, it is still an important risk for allergic individuals and especially for the celiac patients. In order to avoid gluten contamination, producers and consumers should be trained on cross contamination that can occur during food preparation. Keywords: Gluten Contamination, Cross-Contamination, Gluten, ELISA