Recent advancements in red palm oil nanoemulsion systems: a comprehensive review of formulations, characterization, and functional applications

This review explores the development, characterization, and functional applications of red palm oil (RPO) nanoemulsions (NEs), highlighting their potential in the food, pharmaceutical, and cosmetic industries. RPO, extracted from the mesocarp of the oil palm fruit, is naturally rich in bioactive compounds such as carotenoids, tocopherols, tocotrienols, phytosterols, and squalene, contributing to its antioxidant, anti-inflammatory, and cardioprotective properties. However, the hydrophobic nature of RPO limits its application in aqueous systems, reducing its bioavailability and functional efficacy. Nano-emulsification technology addresses these challenges by encapsulating RPO into nanoscale droplets (5-200 nm), enhancing its dispersibility, stability, and bioavailability. RPO-NEs are commonly prepared using high-energy methods (high-pressure homogenization and ultrasonication) or low-energy methods (spontaneous emulsification and phase inversion). Characterization techniques, including droplet size analysis, polydispersity index, zeta potential measurement, and stability testing, ensure the quality and functionality of these systems. Studies have demonstrated that nanoemulsified RPO enhances the absorption and biological activity of carotenoids and tocotrienols, promoting cardiovascular health, anti-inflammatory effects, and skin protection. In the food industry, RPO-NEs improve the fortification of functional beverages and dairy products, while in pharmaceuticals they enhance the delivery of lipophilic nutrients and bioactive compounds. Additionally, RPO-NEs serve as effective carriers in cosmetic formulations, providing antioxidant protection and skin nourishment. This paper comprehensively reviews the formulation strategies, physicochemical properties, health benefits, and diverse applications of RPO-NEs, highlighting their potential as innovative delivery systems for bioactive compounds in various industries. © 2025 Society of Chemical Industry.