Response Surface Modeling for the Inactivation of <i>Escherichia coli</i> O157:H7 on Green Peppers ( <i>Capsicum annuum</i> ) by Ozone Gas Treatment

Abstract

ABSTRACT: : The effects of ozone gas concentration (2 to 8 mg/l), relative humidity (RH) (60 to 90%), and treatment time (10 to 40 min) on inactivation of E. coli O157:H7 on green peppers were studied using response surface methodology. A 3‐factor Box‐Behnken experimental plan was designed and microbial log reduction was measured as a response. The statistical analysis of developed predictive model suggested that ozone gas concentration, RH, and treatment time all significantly (P &lt; 0.01) increased the rate of log reduction of E. coli O157:H7. Among the 3 factors, the effect of ozone gas concentration on bacterial inactivation was the greatest, while the effect of RH was the least. The interaction between ozone gas concentration and RH exhibited a significant and synergistic effect (P &lt; 0.05).