Membrane technologies in the oil industry and their potential application for the recovery of phytonutrients from palm oil

Palm oil is one of the most widely commercialised vegetable oils globally. This oil contains important phytonutrients, such as carotenoids (provitamin A), tocopherols and tocotrienols (vitamin E). These phytonutrients are thermally degraded and removed from crude palm oil (CPO) through bleaching techniques in the refinement process. This article focuses on using membrane technology as a green alternative to recover these compounds, specifically, the use of nanofiltration as a potential mechanism for recovering edible oil phytonutrients from palm oil. Furthermore, due to the few studies related to this topic, the review also highlights microfiltration and ultrafiltration uses in other crude oils (CO) for degumming and deacidification refining processes for phospholipids (Pl) and free fatty acids (FFA) removal. Finally, an overview of the biological functions of palm oil phytonutrients in health and their applications in the food industry is presented.