Response Surface Methodology for Optimization of Sterilization Effect on Fresh-Cut Apple Treated with Acidic Electrolyzed Water

Abstract:

The sterilization effect of acidic electrolyzed water on fresh-cut apple against Staphylococcus aureus, Escherichia coli, salmonella and Listeria monocytogenes cells was studied by response surface methodology and a central composite design with one-factor-at-a-time. Studied variables of NaCl concentration, time, temperature and solid-liquid ratio were selected for the determination of optimal conditions with bactericidal ability evaluated. The optimal conditions were found to be as follows: 6 ：1 liquid-solid ratio (mL/g) and 4.5 g/L NaCl treated under 25 ℃ for 6.45 min. Under these conditions, the total bacteria count was reduced from 1.14×105 CFU/g to 9.3×103 CFU/g and the reduction rate of bacteria was up to 91.84%. Moreover, this treatment slightly affected the pH value and the soluble solid contents of fresh-cut apples, while effectively inhibited the degradation of vitamin c and provided surface browning control.