Assessment of performance of two rapid methods for on-site control of microbial and biofilm contamination

Abstract

(1) Background: The validation of hygiene procedures in food industries is paramount to ensure that food contact surfaces are properly decontaminated before production. Rapid, sensitive and reliable tools are needed for routine hygiene validation in order to increase food safety levels. Two novel tools for biofilm detection (TBF 300) and detection of low levels of microbial contamination (FreshCheck) have been assessed. (2) Methods: Biofilms of relevant food pathogens: Listeria monocytogenes and Salmonella spp. were grown for 3 and 10 days to assess the performance of the biofilm detection product. Surfaces were inoculated with different levels of L. monocytogenes to determine the limit of detection of FreshCheck. (3) Results: TBF 300 visibly stained 3 days-old biofilms of both pathogens, containing 5.0-5.4 log CFU/cm2. FreshCheck showed a positive reaction with contamination levels as low as 10 CFU/cm2 for L. monocytogenes. (4) Conclusions: Assessment of the hygienic status of food contact surfaces before production can be greatly improved with the use of the two novel tools evaluated in this study. The detection of microorganisms' presence at very low levels of contamination as well as identification of biofilm growth spots is available in a rapid and easy way, with a big potential contribution to food safety.