Sébastien Curet

Model-Based Settings of a Conveyorized Microwave Oven for Minced Beef Simultaneous Cooking and Pasteurization

Abstract A major drawback of microwave processing is the heterogeneity of treatment, which prevents from a plenty benefit of its flexibility and rapidity. Most of time, this operation is realized in continuous processes, composed of a series of microwave generators with adjustable power. In this paper is proposed a methodology leading to an optimal setting of these powers in order to warrant the expected microorganisms’ inactivation during simultaneous cooking and pasteurization, while preserving quality. It consists in minimizing a multicriteria formulation including hottest and coldest points on the first hand, and final logarithmic inactivation on the other one. The simulation model is composed of a reduction of the heat equation via a finite volume scheme with a source term deduced from appropriate closed-form solutions of the Maxwells equations, whereas the non-isothermal inactivation is described by the Geeraerd model. The methodology is carried out by considering treatment of minced beef.

Robust Estimation of temperature field during microwave tempering under unknown dielectric properties

Abstract In this paper, a framework is proposed for the estimation of internal temperatures within a foodstuff during microwave tempering under unknown dielectric properties. The solution is based on a partially known model issued from the closed form solutions of Maxwells equations coupled with the conduction heat equation solved by finite differences. The algorithm converges towards acceptable dielectric properties functions whereas the temperature field is estimated simultaneously. This approach is carried out in simulation by considering the tempering of a block of raw beef located in a rectangular wave guide allowing to consider a fundamental mode with perfectly known electromagnetic conditions.