High-voltage electrical discharge-assisted extraction of phenolic compounds from grape seeds

Abstract

This chapter will discuss the high voltage electrical discharges assisted extraction of phenolic compounds from grape seeds. The grape seed, its morphology, and chemical composition are discussed in the first section. In the second section the conventional extraction processes (solid liquid/extraction) and pulsed electric field assisted extraction are compared and discussed. Finally, a special section will be dedicated to high voltage electrical discharge (HVED) in liquid-solid mixture as an extraction process, as it has shown interesting results on this particular raw matter. In this chapter, HVED refers to the formation of an electric arc in a liquid short-circuiting two electrodes, and inducing number of physical phenomena. It is a process that combines the effects of pulse electric field (PEF) with the fragmentation of the raw material. However, HVED is very different from PEF. The physical phenomena related to HVED in water are also complex and not perfectly controlled and understood. The last subsection will adress these phenomena and their relation with the extraction process. The basic knowledge related to HVED (the underlying physics and the material used) will be summed up in order to help understanding this extraction method.