Exposure of Escherichia coli to microwave treatments results in a reduction of the microbial population in apple juice. This research
determined the effect of pasteurisation at different power levels (270–900W) on the microbial quality of apple juice, using a home
2450MHz microwave. Data obtained were compared with conventional pasteurisation (83 1C for 30 s). Apple juice pasteurisation at
720–900 Wfor 60–90 s resulted in a 2–4 logs population reduction. Using a linear model, the D-values ranged from 0.4270.03 min at
900W to 3.8870.26 min at 270 W. The value for z was 652.572.16W (58.570.4 1C). These observations indicate that inactivation
of E. coli is due to heat.