Effects of four kinds of contact surfaces on formation of Bacillus cereus biofilm

To understand the biofilm formation abilities of foodborne pathogenic bacteria Bacillus cereus under food industry-related conditions. Glass, stainless steel, polyvinyl chloride and polypropylene surfaces were chosen as the main surface types of processing equipments where the biofilm of Bacillus cereus formed. Bacillus cereus biofilms were investigated under various food processing environmental conditions such as temperature, pH, sodium chloride, glucose, sodium benzoate and potassium sorbate and the formation of Bacillus cereus were measured by ultrasonic plate method. The results showed that the ability of the formation of Bacillus cereus on four kinds of surfaces was:glass > stainless steel > polyvinyl chloride > polypropylene. The largest biofilm was formed on four kinds of surfaces at 30℃and pH7.0, the formation of Bacillus cereus biofilms was stimulated effectively by 4.0% glucose or 0.5% sodium chloride (p<0.05). 0.15% sodium benzoate and potassium sorbate had better stimulation effect than 0.10% had (p<0.05). These results indicated that food-industry-related conditions could promote Bacillus cereus biofilm formation, which was relevant to food safety. This study established the foundation of the prevention and control of the Bacillus cereus in the food industry, and would provide information on improving the control measures of Bacillus cereus.