Subcritical water extraction of Foeniculum vulgare Mill (Fennel) essential oil

This study extracted the essential oil from Foeniculum vulgare Mill seeds (Fennel) with subcritical water and compared it to the method of Hydro distillation. The important ingredient of essential oil is trans-Anethole. Identification of substances in essential oil and their amount were performed by GC and GC/MS analysis. The effect of temperature, mean particle size, flow rate, and extraction time on the amount, and quality of subcritical water extraction was studied. To facilitate the experiments and investigate the effect of the parameters in their extraction and interaction, used the method of response surface with a central composite design (CCD). The optimum conditions for trans-Anethole extraction happened at a temperature of ۱۲۵ °C and a mean particle size between ۰.۵ and ۰.۷۱ mm in ۶۵ min and a flow rate of ۲۵.۱ mL/min. The total maximum yield (۰.۰۲۳۴۵ mg essence/g dry sample) obtained at the optimal conditions was more than that achieved by the Hydro distillation method (۰.۰۱۳۲۲ mg essence/g dry sample).

Keywords:

extraction , Subcritical Water , Hydro distillation , Foeniculum vulgare Mill , Response surface methodology