Mathematical models of pulsed electric field treatment of plant tissues and simulation of related phenomena

Abstract

Pulsed electric fields (PEF) are very promising for the treatment of plant (vegetable, fruits) and animal tissues. PEF-assisted processing which gives new perspectives for selective extraction and expression, dehydration, drying, freezing, and osmotic treatment can be marked out. However, the nature of electroporation in food tissues is very complicated and can include different scales starting from single membranes and cells to concentrated suspensions and real plant tissues with complex intrinsic structure and much heterogeneity in different scales. Effects of electroporation depend on the size of cells, their orientation and spatial distribution in space, passive and active electrophysical parameters of cells, pH of media, and the presence in tissue osmotic agents. Optimization of PEF treatment and PEF-assisted processing of plant tissues requires precise adaptation of PEF protocols, selection of optimal electric field strength, pulse duration, repetition time, and temperature of treatment. Mathematical modeling can provide detailed and valuable information for optimization of PEF protocols, power consumption, and preservation of the food quality. Moreover, numerical simulation can be useful for description of PEF effects in the presence of complex transport processes and changes in temperature, electrical conductivity, electric field strength, and spatial distribution of electrolyte inside the tissue during PEF treatment. In recent decades various models and simulations were applied for optimizing PEF treatment of liquid foods, geometrical optimization of the treatment chambers, and prediction of the electric field distribution, flow velocity, and temperature inside the treatment chamber. This chapter discusses various models of PEF treatment and computer simulation of related phenomena, which accompanies PEF-assisted processing of plant tissues.