Introduction: Microbiological contamination of food contact surfaces is a major hygiene problem, as microorganisms can cause food spoilage and foodborne infections. Secondary contamination of food with microorganisms attached to kitchen surface is one of the main causes of outbreaks of food-related infections. Cutting boards, various kitchen utensils, cloths, kitchen handles and kitchen counters are the most common source of microorganisms in domestic kitchen. The first and most important step of microbiological surface contamination is adhesion, i. e. initial attraction between microorganisms and the surface. Bacterial adhesion is influenced by environmental factors, surface properties and the properties of microorganisms. Purpose: Purpose of our study was to determine the adhesion level of Escherichia coli to commonly used kitchen surfaces (beech, granite, coated particle board and Teflon) and to determine the effect of UV light on the survival of Escherichia coli on selected surface. Methods: All analysed surfaces were exposed to the same environmental factors. We determined the sourface roughness, wettability and flow potential. The number of adhered bacterial cells was determined by the method of decimal dilution followed by drop plate method. The effectiveness of UV disinfection was determined immediately after contamination of the selected surface with Escherichia coli and after 24 hours of incubation. Results: The highest roughness was measured for wood, followed by Teflon and coated particle board. The most hydrophobic material is Teflon, following by wood, coated particle board and granite. All of the sampled surfaces possess negative charge. Results show the highest level of Escherichia coli on Teflon, followed by coated particle board, wood and granite. We also found that efficiency of UV disinfection is lower after 24 hours when compared to 0,5 h of incubation. Discussion and conclusion: Based on these results, we concluded, that the adhesion of Escherichia coli on chosen surfaces is mainly influenced by hydrophobicity, when compared to surface topography. Moreover, the UV disinfection is more efficient directly after contamination of surface with Escherichia coli, than after 24 hour incubation of bacteria on surface.
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