Attachment and Biofilm Formation of Eight Different Salmonella Serotypes on Three Food-Contact Surfaces at Different Temperatures

<i>Salmonella</i> spp. represent a food safety risk in the production chain because of their potential for biofilm development. This study examined the biofilm formation of eight <i>Salmonella</i> serotypes from diverse foodborne outbreaks on three food-contact surfaces, stainless steel, silicone, and nylon, at 10 °C and 37 °C. The effect of temperature was observed in slower biofilm formation at 10 °C with about 5-log (cfu/cm²) after 24 h, contrasting with 7-log (cfu/cm²) at 37 °C. The material also influenced biofilm formation, with the strongest biofilms on stainless steel at 10 °C and silicone at 37 °C. The serotypes producing the strongest biofilms were <i>S.</i> Enteritidis, <i>S.</i> Saint Paul, and <i>S.</i> Montevideo. The weakest serotypes were <i>S.</i> Senftenberg, <i>S.</i> Anatum, and the avirulent <i>S.</i> Typhimurium. The production of extra-polymeric substances was evident with <i>S.</i> Enteritidis. The biofilm index showed the highest value for low temperature, nylon, and silicone, and for <i>S.</i> Montevideo, <i>S.</i> Enteritidis, and <i>S.</i> Saint Paul. The whole-genome sequencing of each serovar suggested that single nucleotide polymorphisms in the curli (<i>csg</i>) genes may have contributed to the strong biofilm-forming ability of <i>S.</i> Montevideo and <i>S.</i> Saint Paul and the weaker ability of <i>S.</i> Senftenberg. These results can help with the correct development of sanitizing interventions based on the <i>Salmonella</i> strain of concern.