Improving Oil Extraction from Canola Seeds by Conventional and Advanced Methods

Canola seeds are one of the most important sources of edible vegetable oils globally. Crude canola oil is industrially extracted from canola seeds by expeller-pressing of heat-preconditioned flaked seeds. The residual oil in the pressed “canola cake” is recovered by solvent extraction using hexane. However, hexane extraction may pose adverse safety and environmental impacts compared to safer and environmentally friendly alternatives that have been studied recently. This manuscript provides a review of the conventional canola oil extraction process and the state of the art on novel alternatives currently explored to improve oil yield and quality. The latter includes supercritical extraction, aqueous enzyme extraction, microwave, and ultrasound processing. The last two technologies can be implemented either as novel processes or as processing interventions into traditional processes. The levels of technology readiness and the challenges for industrial uptake of each technology are also discussed.