Polyphenol oxidase inactivation and vitamin C degradation kinetics of Fuji apple quarters by high humidity air impingement blanching

In this study, polyphenol oxidase (PPO) and vitamin C were used as the indicators of enzymes and nutrients to evaluate the apple quality during high humidity air impingement blanching (HHAIB) process. The PPO can be completely inactivated within 7 min at 90–120 °C and can retain relatively more vitamin C in the case of PPO fully inactivation. PPO inactivation followed zero‐order kinetics model at 90 and 100 °C, and followed first‐order fraction model at 110 and 120 °C. Activation energy (E_a) of PPO inactivation was between 11.61 and 13.66 kJ mol^?1 by Arrhenius equation. Vitamin C degradation under all processing temperatures was well described by first‐order model and its E_a value was 26.69 kJ mol^?1. Therefore, the HHAIB process was proved to be an effective pretreatment for Fuji apple quarters to inactivate PPO fast and meanwhile to maintain produce quality.