Inactivation ofBacillus cereusbiofilms on stainless steel by acidic electrolyzed water

Abstract

The removal and inactivation of the biofilms remain challenging in the food processing environments. The objective of this study was to examine the efficacy of acidic electrolyzed water (AEW), a novel and green disinfectant, in the inactivation of Bacillus cereus biofilms on stainless steel surfaces. The surviving cell population in the biofilms was less than the detection limit upon inactivation by AEW (pH 2.73) for 15 min. AEW showed good storage stability. The inactivation efficiencies of AEW (>99%) against the biofilms remained high after AEW was stored in a closed and dark system at 35°C for 9 days. The presence of bovine serum albumin had a significantly negative effect on the inactivation efficiency of AEW against the biofilm cells. AEW displayed much higher inactivation efficacies against B. cereus biofilms than chemically modified water with the same pH, available chlorine concentration (ACC), or oxidation reduction potential (ORP). Practical applications Electrolyzed water (EW) has a lot of advantages such as low cost, being environmentally friendly and reduced health concerns, compared with the traditional disinfectants. Acidic EW (AEW) has proved to have a variety of antimicrobial activities. AEW may be a promising non-thermal sanitizer for disinfecting food contact surfaces, particularly those contaminated by the highly recalcitrant Bacillus cereus biofilms.