Seyedeh Fariba Mohammadian Yasuj - Department of Horticultural Science, Yasuj Branch, Islamic Azad University, Yasuj, Iran
Sharareh Najafian - Department of Agriculture, Payame Noor University, Tehran, Iran
Mehdi Hosseinifarahi - Department of Horticultural Science, Yasuj Branch, Islamic Azad University, Yasuj, Iran

The changes in the compositions of essential oils (EOs) from the aerial parts of Thymus vulgaris (garden thyme) were determined at different temperatures and storage times. In this study, the effect of time and temperature on the quality of essential oils was investigated. The essential oil of air-dried samples was obtained by hydro-distillation and was analyzed by gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS). Changes in essential oil compositions were detected during storage for three months in a refrigerator (۴ ◦C), a freezer (−۲۰ ◦C), and at room temperature. In thyme, the amount of the important thymol compound was stable until the first two months, but when entering the third month, a significant decrease was observed in all three temperature conditions. At the same time, a significant increase was observed in the amount of p-cymene in each of the temperature conditions. In the end, we can introduce the best temperature maintenance conditions for thyme at room temperature that can have a lower cost from an economic point of view than other conditions.

essential oil, Storage conditions, Thymol, Thymus vulgaris