Efficacy of chemical sanitizers against Bacillus cereus on food contact surfaces with scratch and biofilm

This study was performed to investigate the efficacy of chemical sanitizers (viz., chlorine, chlorine dioxide, alcohol, and quaternary ammonium compound) against Bacillus cereus on five food contact materials under different conditions (smooth vs. scratched and with vs. without biofilms). After incubating materials in B. cereus suspension, cell adhesion on a smooth surface (10cm(2)) was in the following ascending order: stainless steel (7.36 +/- 0.08 log CFU), glass (7.51 +/- 0.26 log CFU), polyethylene (7.66 +/- 0.30 log CFU), polypropylene (7.76 +/- 0.30 log CFU), and wood (8.02 +/- 0.33 log CFU). The efficacy of sanitizers was dramatically reduced in the presence of a biofilm on all materials. Among four different chemical sanitizers, chlorine showed the best bactericidal activity against B. cereus on the surface with scratch and biofilm. Selection of adequate materials, maintenance of a smooth surface, and inhibition of biofilm formation are good practices for food safety.