Electrostatic field treatment as a novel and efficient method for refining crude canola oil

Abstract

Traditional vegetable oil refining strategies are energy-intensive and can result in substantial oil loss. In metalworking and machine shops, electrostatic “oil cleaners” are used to remove particulate matter (e.g., wear particles, soot, vanish, and dust) from non-polar working fluids with low dielectric constants (e.g., lubricating oil and hydraulic oil). Vegetable oils are also non-polar fluids. Polar contaminants (e.g., phospholipids, free fatty acids, peroxides) can be present in unrefined vegetable oils. The effects of electrostatic field (E-field) applied using a commercial electrostatic “oil cleaner” on crude canola oils were studied. E-field treatments of crude canola oils reduced suspended particles and the contents of phospholipids (reduction of 74.9%), free fatty acids (reduction of 53.2%), and peroxides (reduction of 47.0%). These treatments did not significantly alter either carotenoid content or fatty acid composition. Furthermore, oil loss was negligible (0.37%) during E-field treatment. Therefore, E-field can provide an economical, sustainable, and environmentally friendly alternative to conventional refining methods with minimal oil loss.