Impact of pulsed electric field treatment on the recovery and quality of plant oils

This study examined the impact of pulsed electric fields (PEF) on maize, olives and soybeans for enhanced and gentle recovery of functional food ingredients through induction of stress reactions. A modified process scheme for the production of maize germ oil with increased amounts of phytosterols (up to 32.4%) at simultaneous by higher oil yield (up to 88.4%) was developed. Phytosterols are secondary plant substances and essential metabolites of plant membranes, reducing the serum level of low-density lipoprotein (LDL) cholesterol in humans, associated with atherosclerosis. By using hull fractions during the extraction additionally to a mild application of PEF (0.6 kV/cm) on maize germs, the yield of phytosterols increased by 32.4%. In addition the oil yield of fresh olives increased by 6.5-7.4% depending on the field strength and the amount of the isoflavonoids genistein and daidzein in soybeans increased by 20-21% in comparison to the reference samples. (C) 2004 Elsevier Ltd. All rights reserved.