Inactivation Effect of Radio Frequency Heating on Polyphenol Oxidase and the Analysis of Kinetics
Article
Figures
Metrics
Preview PDF
Reference
Related
Cited by
Materials
Abstract:
In order to investigate the pattern of polyphenol oxidase (PPO) inactivation by radio frequency (RF) heating, the effects of the electrode gap and the electrical conductivity of phosphate-buffered saline (PBS) on the heating rate and inactivation of PPO were studied, and the data were fitted to different models to determine the inactivation kinetics. The results showed that both the electrode gap and conductivity affected the RF heating rate. The larger the electrode gap was, the slower was the rate of temperature increase. When the electrical conductivity was 0.1 S/m, the rate of temperature increase was the fastest. At the electrode gap of 120 mm, conductivity of 0.1 S/m, and RF heating duration of 105 s, the PPO inactivation rate was 91.88%. The first-order kinetics model, Weibull model, and log-logistic model were used to fit the inactivation curve of PPO. The fitness of the three models was evaluated by using a series of indices, including the accuracy factor (Af), bias factor (Bf), root mean square error (RMSE), and correlation coefficient (R2). The curve did not show compliance with first-order kinetics, whereas both the Weibull and log-logistic models could fit the inactivation curve well. The consistencies between measured and predicted values of the three models were examined and the log-logistic model provided the best fitness for the PPO inactivation curve under RF heating.
