Bacteria inside biofilms are more persistent and resistant to stress conditions found in the production environment of food processing plants, thus representing a constant risk for product safety and quality. Therefore, the aim of this study was to characterize, using 16S rRNA sequencing, the bacterial communities from biofilms found in four food processing plants (P1, P2, P3, and P4). In total, 50 samples from these four processing plants were taken after cleaning and disinfection processes. Four phyla: Proteobacteria, Firmicutes, Actinobacteria, and Bacteroides represented over 94% of the operational taxonomic units found across these four plants. A total of 102 families and 189 genera were identified. Two genera, Pseudomonas spp. and Acinetobacter spp., were the most frequently found (93.47%) across the four plants. In P1, Pseudomonas spp. and Lactobacillus spp. were the dominant genera, whereas Lactobacillus spp. and Streptococcus spp. were identified in P2. On the other hand, biofilms found in P3 and P4 mainly consisted of Pseudomonas spp. and Acinetobacter spp. Our results indicate that different bacterial genera of interest to the food industry due to their ability to form biofilm and affect food quality can coexist inside biofilms, and as such, persist in production environments, representing a constant risk for manufactured foods. In addition, the core microbiota identified across processing plants evaluated was probably influenced by type of food produced and cleaning and disinfection processes performed in each one of these.
Keywords: Biofilm; Food; Metagenomics; Microbiota; Next generation sequencing.