The effect of drying conditions on the color of tarragon (Artemisia dracunculus L.) leaves was studied. Tarragon leaves were dried at temperatures of 40 to 90 °C with a constant airflow of 0.6 m/s. The samples were collected at 7%, 10%, 20%, and 30% moisture content wet basis for evaluation of the color change. The color parameters of fresh and dried leaves were measured by a colorimeter. The individual parameters of L*a*b* and L*C*h° color systems were evaluated and h° proved to be the best parameter to monitor color change. The smallest change of the color parameters was observed at 40 °C, in which temperature was low, and also at 90 °C, when drying time was short. The biggest change occurred at the temperatures of 50 to 70 °C. Most of the color change happened before the material reaches 35% moisture content. The combination of drying time and temperature defines the change of color.
- thermal kinetics