Kinetics mass transfer and modeling of tarragon drying (Artemisia dracunculus L.)

In this study, the thin layer drying kinetics of Tarragon (Artemisia dracunculus L.)was modeledin a hybrid dryer. Experiments were performed at four temperatures of 40, 50, 60, 70ºC and three air velocities of 1, 1.5 and 2 m/s in the factorial arrangement based on a completely randomized design. According to the results of analysis of variance, the effect of drying air temperature and drying air velocity were significant at 1% probability level. However, the interaction effect of temperature and drying air velocity was not significant. The highest essential oil content was related to the temperature of 40°C and an air velocity of 1.5m/s with an approximate value of 1.27CC (v/w). With increasing temperature from 40°C to 70°C, the essential oil content decreased significantly. According to the obtained results, the Agbashlo et al. model could estimate the kinetic curve of tarragon drying better than other models. The effective moisture diffusivity values were achieved to be in the range of 1.34×10−10-2.74×10−10 m2/s.