Farhad Abdi-Gaol - M.Sc., Department of Mechanical Engineering of Biosystems, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran
Ali Asghari - Associate Professor, Department of Mechanical Engineering of Biosystems, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran
Safoora Zadhossein - B.Eng., Department of Mechanical Engineering of Biosystems, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran

Mentha leaves were dried in hot-air drying using 3 different air temperatures (60, 70 and 80°C) with velocity of 1 m/s. In this study, measured values were compared with predicted values obtained from twenty one thin layer drying theoretical/ semi empirical/ empirical equations. Also a novel model of kinetics of thin layer drying is tested in this study. Models with highest coefficient of correlation (R2) values were chosen as the best models. According to this, the introduced model showed the best coefficient of correlation for all of temperatures.

Mentha leaf, Moisture Ratio, Thin-layer Drying Models, Hot-air drying