Microwave processing of food samples: influence of cavity design and dielectric properties

Abstract

[EN] Microwave-material interactions and electromagnetic propagation phenomena are important to optimize the microwave heating process of food samples. In this study, a 3D numerical modelling of a TE10 rectangular waveguide including microwave antenna and impedance matching elements is proposed. The microwave applicator is aimed to process both solid and liquid food samples. The model illustrates the standing wave patterns and microwave absorbed power within the cavity by taking into account the influence of the screw tuner, quartz windows, shorting plunger, and additional dielectric support plates. The results reveal the importance to consider the real cavity design and the precise dielectric characterization to predict accurate temperature profiles within the food product during the microwave heating. Such a model can be now be used to optimize the food sample geometry to achieve minimum reflected power and better heating uniformity.