A dynamic and generic model of gas exchange of respiring produce: the effects of oxygen, carbon dioxide and temperature

Abstract

Abstract A generic model is developed that describes rates of respiration and fermentation, in response to temperature and environmental gas conditions (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. Fermentation is modelled including the competitive inhibition of fermentation by both oxygen and carbon dioxide. Temperature dependence is introduced using Arrhenius equations for the maximum rates of oxygen consumption and carbon dioxide production. The model is generic in nature: it is applicable to different types of products (apple, chicory and tomato) at different conditions (in terms of O2, CO2 and temperature) and for different types of inhibition. This fitness is an indirect validation of the assumptions on which the model is based.