Cruz, AnaGuiné, RaquelGonçalves, João Carlos2014-11-212014-11-212015Cruz AC, Guiné RPF, Gonçalves JC. (2015) Drying Kinetics and Product Quality for Convective Drying of Apples (cvs. Golden Delicious and Granny Smith). International Joournal of Fruit Science, 15(1), 54-78http://hdl.handle.net/10400.19/2375Our work studied the convective drying of apples from two different cultivars, Golden Delicious and Granny Smith, in a range of temperatures from 30 to 60 ºC. Some chemical and physical properties were determined fresh and after drying: moisture, acidity and sugars contents, 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. We 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 Deo was 5.4621x10-4 and 1.8401x10-4 m2/s, and E was 35.3 kJ/mol and 32.8 kJ/mol, respectively for cultivars Golden and Granny Smith.engDiffusion coefficientMass transfer coefficientDried appleConvective dryingTextureColorjournal article