A Desiccant-Based Food Drying System with Humidity and Temperature Control

Drying and maturation processes are widely used for food production, but a real scientific approach is not yet applied, so rather empiric rules are used to set up industrial production. Often the food humidity control is obtained by a regulation of the R.U. an dthe room temperature, taking into account the water evaporation inside the food matrix according to the arranged air velocity. The system proposed in this paper consists of a humidity and temperature control during the food drying process by using a particular dehumidifier equipped with a desiccant rotor containing silica gel. Through experimental evaluations it's demonstrated that dried products as vegetables and fruits treated by this method retain their fresh color, their texture and their organoleptic conditions to ensure their finla quality. Moisture sorption isotherms for different product are done to determine the water activity and for the prediction of evaporative losses. Experimental data are vaidate by a unidimensional simulation model.