Electrofluidic pretreatment for enhancing essential oil extraction from citrus fruit peel waste

Abstract

Pretreatment technologies make pressed fruit peel more valuable both nutritionally and economically. Robust electrofluidic systems, in particular, can facilitate clean and efficient production of valuable compounds from these byproducts. In this study, a multi-series system was designed with a combination of pipeline flow and induced electric field (IEF), then applied to pretreat citrus peel for enhancing the extraction of essential oils. The essential oil yield increased significantly from 0 V to 1 kV. There was a decrease in fluid impedance during the IEF-pretreatment period owing to the dissolution of cell contents, as well as a slight decrease in essential oil yield as frequency increased. Forty components were identified in the essential oils representing over 97% of the total GC peak areas for both procedures. We also observed significant effect on the essential oil yield between the IEF-pretreatments in different winding direction of the sample coils. High throughput was achieved by arbitrarily increasing the reactors within a compact system. In effect, the IEF-pretreatment is an effective, innovative, and ecologically sustainable technique for intensifying essential oil extraction without necessitating metal electrodes, thus avoids electrode surface corrosion, and heavy metal contamination.