Effect of carbon dioxide on the inactivation of florida spiny lobster polyphenol oxidase

Florida spiny lobster ( Panulirus argus ) polyphenol oxidase (PPO) exposed to CO 2 (1 atm) at 33, 38, and 43°C showed a decrease in enzyme activity with increased heating time. Enzyme inactivation by CO 2 was faster for PPO heated at 43 than at 33 or 38°C. Inactivation kinetics revealed PPO was more labile to CO 2 and heat in the range 33–43°C than to heat alone. Kinetic data also revealed that CO 2 , in addition to pH changes, was involved in the loss of PPO activity. Studies using get electrophoresis showed no differences in protein patterns and isoelectric point between CO 2 ‐treated and non‐treated control. The pH of CO 2 ‐treated PPO stock solution was brought back from 5.4 to 8.0 after 6 weeks of frozen‐storage and no enzyme reactivation was observed.