Optimization of producing oil and meal from canola seeds using microwave − pulsed electric field pretreatment

Abstract

In this study, optimization of the extraction of canola seeds oil was investigated using microwave-pulsed electric field seeds pretreatment (MW-PEF) with different MW times (0 to 200 s) and PEF intensities (0 to 5 kV/cm). The seeds oil was then extracted using screw press with different speeds (11 to 57 rpm). Oil extraction efficiency, refractive index, peroxide and phenolic compounds of oil and meal protein were measured. Tocopherols content of the best sample was also measured. The results showed that the peroxide and phenolic compounds increased at higher time, intensity and speed. An increase in the MW time and PEF intensity at first led to an increase in the oil extraction efficiency and meal protein but then both parameters decreased. The efficiency of oil extraction and protein decreased at higher speeds. The refractive index of all samples was 1.475. Gamma tocopherol was predominate one in canola oil and applying the pretreatment led to an increase in the number of total tocopherols. Treating at 1.28 kV/cm for 140.5 s and 28.71 rpm was chosen as the optimum condition with high desirability (0.744).