Pulsed electric energy-assisted extraction of polyphenols from flaxseed hulls and cake

Abstract

This chapter deals with the recent advances in the pulsed electric energy (PEE) assisted extraction of polyphenols from flaxseed hulls and flaxseed cake. Among these technologies, pulsed electric fields (PEF) and high voltage electrical discharges (HVED) have been applied. Some of the currently published results are presented in this chapter. Both PEF and HVED treatments have shown their efficiency for the recovery of total polyphenols and lignan. For the effective recovery of solutes from PEE treated flaxseed hulls and cake, following alcoholic extraction and alkaline hydrolysis are needed. Such methodology allows increasing both the extraction kinetics and the final extraction yield of total polyphenols. The corresponding diffusion coefficient of polyphenols is also higher from electrically treated samples. The subsequent purification step for polyphenols recovery can be performed by using membrane technology and particularly ultrafiltration. The ultrafiltration of flaxseed hull extract may be a promising method for separation of polyphenols and proteins, since it resulted in high degree of purification, which cannot be attained by simple coagulation and centrifugation.