Abstract
A genus of Satureja with the Persian name of “Savory” is one of medicinal plants of the family Lamiaceae This experiment was conducted to investigate the effect of different drying methods on the quantity and quality of essential oils of Savory. The essential oils from shade, IR, hot air and ultrasonic dried samples were isolated by hydrodistillation in a Clevenger apparatus and analysed by gas chromatographymass spectrometry (GC-MS). The results obtained in this study indicated a significant effect of the ultrasound method in reducing the drying time at low temperature to maintain the yields and quality of essential oils of Satureja bachtiarica. By increasing the temperature from 40 to 60°C, the amount of p-Cymene in the hot air, infrared and ultrasonic methods reduced to 8 %, 3 % and 6 %, respectively, and that of γ-Terpinene reduced to 14.5 %, 14.9 % and 12.5 %, respectively. The ultrasonic drying method gives rise to increasing monoterpenes hydrocarbon content of the dry shade treatment from 32.46 % to 39.46 % in the dried treatment at 40°C. Given that the drying time the ultrasound method is lower than other treatments, and the yield of essential oils in the ultrasound treatment at 40°C is higher than other treatments, therefore, if the quality and yield of essential oils consider, the ultrasonic drying at 40°C is recommended.