Improvement of heat & mass transfer with added ozone into drying air on corn-soy

Abstract

Corn and soy have wide-ranging uses in food and biofuel industries due to its nutritional and energetic properties. In the present work, artificial drying experiments with hot air convection in different temperatures (30, 40 and 50 °C) were carried out with the addition of ozone (5, 10 and 15 min) applying a central composite design (CCD). The effective diffusion coefficient D_eff as thermodynamic properties was evaluated with and without the incorporation of ozone into drying air on corn and soy. The CCD showed different D_eff values and a numeric model was fitted to moisture diffusion during the drying-ozonation process (DOP) on corn-soy. Activation energy decreased from 43.90 to 35.20 kJ mol⁻¹ for corn and 38.23 to 34.29 kJ mol⁻¹ for soy when ozone was added into the drying air; similar observation occurred to enthalpy and entropy. Thus, the drying-ozonation process can be useful for technological purposes for energy improvement during postharvest stages, as well as maintaining the quality of cereal products and design of new dryers.