Non invasive Determination of Temperature Trajectories During a Defrosting Process using Microwave Radiometry

The control of the freezing or defrosting velocity is an important parameter in food industries, for the improvement of product quality. In this paper, radiometric measurements, a noninvasive method, are shown to be effective to follow the defrosting of foodstuff. We describe experiments and the radiometric device used. Simulations based upon the combined algorithms FDTD - heat transport equation are used to predict the radiometric temperature trajectories during the defrosting process by introducing the temperature dependent media. The comparisons between experimental and theoretical results are presented and analyzed.