Inactivation Kinetics of Polyphenol Oxidase from Banana Pulp by High-Pressure Carbon Dioxide

In this paper,effect of high-pressure carbon dioxide on inactivation of polyphenol oxidase(PPO) from banana pulp was studied,and inactivation kinetics of PPO was analyzed by using a two-fraction model.Results showed that the inactivation of PPO by high-pressure carbon dioxide could be significantly affected by the pressure of carbon dioxide,processing temperature,processing time and sample pH.The inactivation kinetics of PPO was adequately described by using a two-fraction model.High pressure carbon dioxide treatment was an effectively way to inactivate PPO from banana pulp,and the inactivation rate of PPO could be significantly increased by improving carbon dioxide pressure and treatment time,and decreasing sample pH.The reduced residual activity of PPO exposed to high-pressure carbon dioxide(20 MPa,55 ℃) was 83.5% for 40 min,and only 4.2% of enzyme activity was remained when treated with high-pressure carbon dioxide(20 MPa,60 ℃) for 20 min.