The convective drying of apples from two different cultivars, Golden Delicious and Granny Smith, in a range of temperatures from 30 to 60 • C is studied. Some chemical and physical properties were determined fresh after drying: moisture, acidity and sugar content, color, and textural attributes, in order to evaluate the effect of drying and drying temperature on these properties. Furthermore, the drying kinetics were studied in terms of thin layer models and also by means of the Fick's equation of diffusion, and some mass transfer properties were evaluated, such as effective moisture diffusivity and convective mass transfer coefficient. It was concluded that drying decreased both acidity and sugar content for both apple cultivars. Color was significantly affected by drying, resulting in high values of the total color difference, between 19.43 and 25.04. Drying turned the products less hard and less cohesive. Furthermore, it was found that mass diffusivity increased with temperature following an Arrhenius type function, where D e 0 was 5.4621 × 10 −4 and 1.8401 × 10 −4 m 2 /s, and E was 35.3 and 32.8 kJ/mol, respectively, for cultivars Golden Delicious and Granny Smith.

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