Numerical simulations of pulsed electric fields for food preservation: A review

The application of pulsed electric fields is a novel technique to preserve foods in a non-thermal way. One key component of this technology is the treatment chamber, in which the food is exposed to a pulsed electric field to induce permeabilization of biological cells, e.g. to inactivate microorganisms. For a high efficiency of the method and a high product quality a detailed knowledge of the electric field strength and temperature distribution in the chamber is necessary. The numerical simulation of the fluid dynamics coupled with the electric and thermal fields inside the treatment chamber can provide such information with high spacial and temporal resolution. An important goal of the simulations is the optimization of the treatment chamber geometry to improve the uniformity of the electric and thermal fields between the electrodes in order to avoid the over or under-processing of foods or dielectric breakdowns. This article reviews numerical investigations performed on the pulsed electric field process and presents numerical results of a treatment chamber optimization and the solution of coupled fluid dynamical, electrical and thermal problems. Industrial relevance: Numerical simulations of the pulsed electric field process provide detailed information of the fluid flow, the temperature and the electric field distributions in treatment chambers under various conditions. Such local information inside the electric field is difficult to obtain experimentally. For a further development of the pulsed electric field technology, numerical simulations can be applied to improve the fundamental understanding of the physical phenomena occurring and to optimize the process with respect to the chamber design and operating conditions. (c) 2008 Elsevier Ltd. All rights reserved.