This study demonstrates that data from models simulating use conditions are required to estimate the effectiveness of detergent-based removal practices and how these can be enhanced by inactivation processes such as drying and disinfection to ensure that contamination from food-borne pathogens is reduced to acceptable levels to prevent infection transmission.

No abstract

Stainless steel coupons are frequently used in biofilm studies in the laboratory, as this material is commonly used in the food industry. The coupons are attached to different surfaces to create a "natural" biofilm to be studied further in laboratory trials. However, little has been done to investigate how well the microbiota on such coupons represents the surrounding environment. The microbiota on sink wall surfaces and on new stainless steel coupons attached to the sink wall for 3 months in 8 domestic kitchen sinks was investigated by nextgeneration sequencing (MiSeq) of the 16S rRNA gene derived from DNA and RNA (cDNA), and by plating and identification of colonies. The mean number of colony-forming units was about 10-fold higher for coupons than sink surfaces, and more variation in bacterial counts between kitchens was seen on sink surfaces than coupons. The microbiota in the majority of biofilms was dominated by Moraxellaceae (genus Moraxella/Enhydrobacter) and Micrococcaceae (genus Kocuria). The results demonstrated that the variation in the microbiota was mainly due to differences between kitchens (38.2%), followed by the different nucleic acid template (DNA vs RNA) (10.8%), and that only 5.1% of the variation was a result of differences between coupons and sink surfaces. The microbiota variation between sink surfaces and coupons was smaller for samples based on their RNA than on their DNA. Overall, our results suggest that new stainless steel coupons are suited to model the dominating part of the natural microbiota of the surrounding environment and, furthermore, are suitable for different downstream studies.Key words: microbiota, stainless steel coupons, sink surface, domestic kitchens. Résumé :Les études sur les biofilms utilisent couramment des coupons en acier inoxydable en laboratoire puisque ce matériau est répandu dans l'industrie alimentaire. Ces coupons sont attachés à diverses surfaces afin de créer un biofilm « naturel » aux fins d'études plus approfondies en laboratoire. Or, on s'est peu demandé à quel point la microflore retrouvée sur de tels coupons est représentative de l'environnement avoisinant. On a examiné la microflore de nouveaux coupons d'acier inoxydable attachés à la paroi de l'évier pendant trois mois, ainsi que celle des parois de l'évier comme telles, au moyen du séquençage de prochaine génération (MiSeq) du gène de l'ARNr 16S issu d'ADN et d'ARN (ADNc), et par ensemencement et identification des colonies. Le nombre moyen d'unités formant colonies était environ 10 fois plus élevé sur les coupons que sur les surfaces de l'évier, et on a observé davantage de variations des numérations bactériennes selon les cuisines dans le contexte des surfaces d'éviers que des coupons. La microflore de la majorité des biofilms était dominée par les Moraxellaceae (genre Moraxella/ Enhydrobacter) et les Micrococcaceae (genre Kocuria). Les résultats ont démontré que la variation de la microflore était principalement attribuable aux différences entre les cuisines (38,2 %), suivie par les ...