Inactivation kinetics and photoreactivation of vegetable oxidative enzymes after combined UV-C and thermal processing

摘要: Abstract The inactivation kinetics of lipoxygenase (LOX), peroxidase (POD) and polyphenoloxidase (PPO) in phosphate buffer (pH 4.0 7.0) treated by combined thermal (25–65 °C) UV-C (1–10 min) processes were fitted using a traditional first-order model the Weibull distribution function. For complete inactivation, treatment at 65 °C for 7.5–10 min LOX, POD PPO pH 7.0 45 °C 5–7.5 min pH 4.0 was necessary. Deviations from log-linear behavior observed appearance shoulders, tails or both (sigmoidal). failed to characterize UV effectively due under- overestimation enzyme inactivation. better able explain nature treatment. extent less orange juice greater absorbance range. In general, activities residual enzymes after did not recover storage 24 h refrigeration conditions with without light exposure. proposed combination processing improve stability samples. Industrial relevance irradiation has demonstrated be an effective technology decontaminate surfaces reduce microbial load liquid food low cost, simple chemical-free manner. However, its application pasteurization needs validated against achieving adequate enzymatic stability. A kinetic study on quality-related (peroxidase, polyphenoloxidase) (25–65 °C 1–10 min) conducted. (45–65 °C 5 min) achieve reduction activity. matrix. Enzymes irreversibly inactivated storage.