Mathematical Model of Gas Exchange for Modified Atmosphere Packaging Containing Pak-choi

Abstract: Respiration became the dominant aspects of metabolism after vegetables were harvested. The main factors affecting respiration are temperature and gas concentration of the storage environment. It is a major challenge that how to choice a plastic film with appropriate permeability coefficient for specific varieties veg-etables in specific temperature. Therefore, it is the key of modified atmosphere packaging technology of vege-tables that to establish mathematical model of gas exchange for modified atmosphere packaging (MAP). Based on the dynamic equilibrium theory of MAP, the variation laws of respiration rates were studied with the dynamic changes of O2 and CO2 concentration within packages at 10 ℃ and 20 ℃ respectively. The opti-mal simulated function expression was established. The experimental data were analyzed with SPSS for win-dows statistical software. The mathematical model of gas exchange within close packages was developed when the modified atmosphere packaging for Pak-choi was designed. The theoretical basis for getting a right way to choose packaging materials for MAP and predicting the gas mass concentrations inside the packages were provided.The correctness of model was verified by MAP experiments containing Pak-choi