Purpose: The aim this study was analyzed the correlation between biofilm formation in different materials and the presence of the genes adrA and csgD. Tolerance of the biofilm against common sanitizers used in the industry (chlorinated alkaline cleaners, peracetic acid, and the two combined) was also evaluated.
Methods: Biofilm-forming ability of 98 strains isolated from conveyor belts of poultry cutting rooms was evaluated in polystyrene plates, also was analyzed in 1-cm2 polypropylene (PP) and polyurethane (PU) slides, and the slides were analyzed by scanning electron microscopy. Sanitizer efficiency was evaluated after 96-h incubation for biofilm formation, viable cells were removed from the surfaces soon after the treatment, and after reincubation for 96 h, by vortexing tubes with glass beads.
Results: Only one strain was a strong biofilm-producer in polystyrene, ability to produce microfilms was weak in 70% of strains, and moderate in 29% and both genes were found in all strains. Important differences in adhesion were observed between the materials, scanning electron microscopy showed that PU had a more irregular surface. No viable cells were recovered in PP slides treated with sanitizers, in PU the reduction in viable cell counts observed soon after sanitizer treatment was enough to consider that sanitizers were efficient, after reincubation, this difference was smaller for the treatment with peracetic acid.
Significance: The results of this study are a warning in food safety, due to the importance of the isolation of strains that are able to produce biofilms both on in vitro testing materials and in materials that are used as cutting surfaces in poultry processing plants.