Classic and Reaction-Diffusion Models Used in Modified Atmosphere Packaging (MAP) of Fruit and Vegetables

Fruits and vegetables continue metabolic processes after being harvested. In some produce, mainly climacteric fruits, these processes cause deterioration of the produce during storage. To reduce the deterioration rate, several strategies have been implemented for postharvest handling. One of these preservation strategies is modified atmosphere packaging (MAP). In this technology, the respiration rate of the produce and the gas permeability of the storage film are the two fundamental kinetic processes accounted for in designing the packaging system. To understand the relationship of these two kinetic processes during packaging in modified atmospheres, two major techniques have been presented from the standpoint of mathematical modeling: the classic respiration rate models and the reaction-diffusion model. In the classic model of respiration rate, four types of black box model approaches have been proposed: linear, polynomial, exponential, and the Michaelis-Menten kinetic models. For the last black box model, four types of inhibition approaches are considered: competitive, uncompetitive, noncompetitive, and, finally, a combination of competitive and uncompetitive inhibition. In the reaction-diffusion model, it has been considered that the transport of a species in modified atmosphere packaging (mass transport in the headspace and the film used as packaging) obeys strictly diffusive transport models. For this reason, the main objective of this review is to show the advances in the two major techniques (classic respiration rate models and the reaction-diffusion model) implemented to describe the MAP of fruit and vegetables, as described in specialized literature.