A respiration rate model, based on enzyme kinetics and the Arrhenius equation, was proposed for predicting respiration rates of fresh apple as a function of O2and CO2concentration and storage temperature. Several experiments were conducted at different storage temperatures for generating respiration data by using a closed system method of respiration measurement. In this model, the dependence of respiration rate on O2and CO2was found to follow the uncompetitive inhibition. The enzyme kinetic model parameters, calculated from the respiration rate at different O2and CO2concentrations, were used to fit the Arrhenius equation against different storage temperatures. The activation energy and respiration pre-exponential factor could be used to predict the model parameters of enzyme kinetics at any storage temperature between 0 and 30°C. Respiration rates of apple predicted by the proposed model were found in good agreement with those obtained experimentally.
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