Sodium hypochlorite-mediated inactivation of Cronobacter spp. biofilms on conveyor belt chips

Chlorine bactericidal effects on Cronobacter vegetative cells and biofilms on conveyor belt chips were evaluated. Cronobacter vegetative cell isolates were inactivated after 10 min chlorine exposure (10 ppm). No efficacy difference was observed between pH-adjusted and pHunadjusted sodium hypochlorite solutions. The pH-adjusted solution was more effective at reducing the bacterial population in a biofilm. The number of cells in the biofilm on a Buna-N chip decreased by 3 log after exposure to 100 ppm of pH-adjusted chlorine and for PVC by 2.21 log after exposure to 400 ppm of pH-adjusted solution. The rate of biofilm reduction is dependent on the composition of the conveyor belt, concentration of chlorine, and pH of the chlorine solution.