A Theoretical Model for the Control of Color Degradation and Microbial Spoilage Occurring in Food Convective Drying

S. Curcio[1], M. Aversa[1]
[1]University of Calabria, Department of Engineering Modeling, Rende, Cosenza, Italy

The aim of this work was the development of a predictive model aimed at identifying a proper control strategy of food drying process. In particular, it was intended to determine the effect of operating conditions both on the color degradation, chosen as a reference quality parameter, and on the microbial spoilage occurring during potatoes drying. A transport model, accounting for the simultaneous transfer of momentum, heat and mass occurring in the drying air and in the food sample, was formulated and coupled both to a product decontamination model, describing the microbial inactivation kinetics of Listeria monocytogenes and to another model aimed at predicting the kinetics of color changes occurring during drying. The proposed model allowed determining, on the basis of a dynamic optimization algorithm, a trajectory of operating conditions that has to be tracked by means of proper control systems so as to optimize the performance of drying process.