Salmonella Biofilm on Food Contact Surfaces and the Efficacy of Chemical Disinfectants: A Systematic Review

Abstract

Foodborne illness has always been a major public health concern, usually caused by cross-contamination during food preparation. Salmonella is one of the most reported pathogens, which can attach to and survive on food contact surfaces by forming a biofilm. Biofilm formation enhances the persistence of food pathogens and protects them from external threats, and increases their resistance to chemical disinfectants. This systematic review aims to obtain an overview of the Salmonella biofilm formation on food contact surfaces and the efficacy of chemical disinfectants based on the latest scientific data. Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines were used to carry out the study. From the review, plastic (91%), stainless steel (64%), and sodium hypochlorite (86%) were most commonly tested. Most chemical disinfectants used in the reported studies were sodium hypochlorite (NaOCl, 100–500 mg/L), hydrogen peroxide (H2O2, 0.56%), and benzalkonium chloride (BAC, 100–400 µg/ml). The result showed that Salmonella contamination was more common on hydrophobic food contact surfaces like wood and concrete than on hydrophilic surfaces like glass. In addition, the previous studies also revealed that biofilm formation on stainless steel, plastic, and silicone rubber surfaces was not significantly different. Plus, most chemical disinfectants showed inefficacy in eliminating Salmonella biofilm at regular concentrations (<0.05%). It shows that frequent cleaning is important to avoid biofilm formation and ensure the maximum efficacy of the sanitisers.