Effects of ultrasound and microwave pretreatments on hydrodistillation extraction of essential oils from Kumquat peel.

Abstract

Main objectives of this work were to investigate the influences of ultrasound pretreatment (UP) and microwave pretreatment (MP) on extraction kinetics, chemical composition, and antioxidant activity of Kumquat peel essential oil (EO) obtained by hydrodistillation extraction (HDE). The effects of ultrasound power and processing time, and microwave power and processing time were evaluated. As compared with HDE individually, UP and MP decreased the extraction time, increased the yield and DPPH radical‐scavenging activity but did not noticeably affect chemical composition of the EO. For UP and MP, the highest EO yield was obtained when the ultrasonic power and processing time, and microwave power and processing time were 210 W and 30 min, 300 W and 6 min, respectively. In comparison with MP, UP gave a higher yield and DPPH radical‐scavenging activity of the EO. Overall, UP and MP are promising techniques for HDE of EO from kumquat peel.