Inactivation kinetics of peroxidase and polyphenol oxidase in peach juice treated with gaseous ozone

Abstract

The effectiveness of gaseous ozone for inactivating peroxidase ( POD) and polyphenoloxidase ( PPO) in peach juice was investigated. The suitability of first‐order and Weibull models to describe inactivation kinetics was also analysed. Peach juice was exposed to ozone (0.11 and 0.20 mg O ₃ min ⁻¹  mL ⁻¹) in a bubble column up to 12 min at 20 ± 1 °C. Enzyme activities were reduced due to treatments. The magnitude of the inactivation increased with ozone level and exposure time. Reductions in activity after 12 min of treatment ranged between 99.5% and 99.8% for POD and between 93.9% and 97.3% for PPO, depending on ozone concentration. Inactivation curves were successfully fitted with the first‐order and Weibull models; although, based on the root‐mean‐square error, the corrected Akaike and the Bayesian Schwarz criterion, the Weibull model showed stronger capability in all cases.