Modeling drying kinetics of yellow potatoes (Solanum gonyocalix)

The aim of this research was to model drying kinetics of potatoes ( Solanum gonyocalix ), variety Amarilla Tumbay, using a tunnel dryer.  Potatoes slices of 0,5 cm thickness were used in a drying experiment at different temperatures (60, 70 and 80°C) and air speed (4,9, 6,7 and 8,3 m/s). The equipment used allowed recording of the sample gross mass at real time. A factorial design in CRD with two repetitions was used, to determine significant differences between levels the LSD method was used. The results show two drying speeds (a very short constant one and a decreasing one).  For the marked decreasing speed, which could be modeled by Fick´s law of diffusion, the used equations were adequate for a proper description of the process. Temperature dependence of moisture diffusion was of the Arrhenius equation type (R2 = 0.995): moisture diffusion and activation energy were Do = 0,81x10-9 m2/s and Ea = 4,81 kJ/mol respectively.