CONICET | Buscador de Institutos y Recursos Humanos

Abstract Moisture diffusivities in high oleic seeds and kernels were obtained from experimental thin-layer drying rates between 25 and 90°C air temperature and between 4.22 and 33.51 % dry basis initial moisture content. Moisture diffusivity obtained from the second Fick´s law of diffusion varied between 0.847.10-10 and 7.256.10-10 m2/s for seeds and between 0.370.10-10 and 2.389.10-10 m2/s for kernels. The activation energy based on an Arrhenius-type relationship resulted 21.8 % higher in seeds than in kernels, obtaining values of 30.7 and 24 kJ/mole, respectively. Based on the significative interaction (P<0.05) between moisture diffusivity with temperature and initial moisture content, two non linear models were proposed to estimate moisture diffusivity in seeds and kernels based on kinetic Page parameter and the moisture content. The proposed equations showed good agreements (R2>0.99 for seeds, R2>0.96 for kernels, both significant at P<0.05). The comparison between experimental moisture ratio with the proposed models showed that moisture diffusion based on the Page kinetic parameter with temperature dependence represents a good and simple tool, with low relative errors (lower than 10%) to predict drying behavior of high oleic sunflower seeds and kernels based on diffusion mechanism.