Application of pulsed electric energies for oil and polyphenol extraction from sesame cake and sesame seeds

Abstract

Sesame is a widely cultivated oilseed and both its cake and oil present high nutritional quality and economic value. The importance of this seed has grown as new research is made. Initial research has been performed in the application of pulsed electric fields (PEF) and high voltage electrical discharge (HVED) technologies on sesame cake and sesame seeds. Some of the currently published results are presented in this chapter. HVED technology is based on the phenomenon of electrical breakdown in water, which induces physical and chemical processes. Both pulsed electric fields and high voltage electrical discharges efficiently damaged sesame seed cells; this damage increased with the applied energy input. The permeabilization caused in the seeds by the electrical treatments significantly raised the oil yield when compared to untreated seeds. However, a significant amount of oil was lost in water during the electrical treatment step. The results also demonstrated that extraction assisted by PEF or HVED could be effective techniques to increase yield of polyphenol, lignan, and protein extraction from sesame cake and improve kinetics of diffusion. These technologies can potentially reduce the use of ethanol as a solvent for phenolic compounds extraction and the need of higher temperatures to improve diffusion.