. after 45 min of ozone treatment. This supports the findings of the current study in the way that ozone with mild heat treatment showed greater antimicrobial effect than ozone treatment at ambient temperature. Our study confirmed that ozone treatment at 50 °C was highly effective in the reduction of pathogens in apple juice. In the case of E.coli O157:H7, the effect of ozone itself resulted in about a 1.50 log CFU/ml