A DYNAMIC AND GENERIC MODEL OF GAS-EXCHANGE OF RESPIRING PRODUCE - THE EFFECTS OF OXYGEN, CARBON-DIOXIDE AND TEMPERATURE

A generic model is developed that describes rates of respiration and f ermentation, in response to temperature and environmental gas conditio ns (oxygen and carbon dioxide). The mathematics of the model are based on Michaelis-Menten kinetics. Respiration is simplified as the effect of one enzymic reaction, inhibited by its own product, carbon dioxide . Both competitive, and uncompetitive inhibition are incorporated. Fer mentation is modelled including the competitive inhibition of fermenta tion by both oxygen and carbon dioxide. Temperature dependence is intr oduced using Arrhenius equations for the maximum rates of oxygen consu mption and carbon dioxide production. The model is generic in nature: it is applicable to different types of products (apple, chicory and to mato) at different conditions (in terms of O-2, CO2 and temperature) a nd for different types of inhibition. This fitness is an indirect vali dation of the assumptions on which the model is based. (C) 1998 Elsevi er Science B.V. All rights reserved.