Effects of the drying temperature on essential oil content of bay leaf (Laurus nobilis L.) harvested at different times

Bay leaf essential oil is one of the main products from bay trees that are used in food, spice, flavoring and cosmetic industries. Drying is an important post-harvesting process, which affects the essential oil content and the quality of bay leaf. In the present study, the effects of drying temperatures on the essential oil contents of bay leaf harvested at different times were studied. The leaves were harvested in the months of October, December, January, February, April and June and then dried in the cabinet dryer at 35, 50, 65 and 80 degrees C for 12 hours. The essential oil contents in dried bay leaf samples were determined by hydrodistillation. According to our results, essential oil contents of dried bay leaves varied from 2.02% to 3.02% by different harvesting time and drying temperatures. The highest values were obtained in 35 and 50 degrees C drying temperatures for the October harvest. Higher drying temperatures caused greater loss in the essential oil content.