Development of Curcumin-Loaded Nanoemulsions for Fortification and Stabilization of Dairy Beverages

Curcumin is a polyphenolic compound isolated from Curcuma longa, which is widely recognized for its therapeutic properties: particularly its strong anti-inflammatory and antioxidant activities. However, its practical incorporation into functional foods, especially aqueous dairy beverages, is severely hindered by its extremely low water solubility, poor chemical stability (notably at the near-neutral pH of milk), and very limited oral bioavailability. This review provides a critical synthesis of the literature published in the last two decades, with a focus on the development and application of food-grade oil-in-water (O/W) nanoemulsions to advanced colloidal delivery systems. It covers the fundamental principles of nanoemulsion formulation, including the selection of the oil phase, surfactants, and stabilizers, as well as both high-energy and low-energy fabrication techniques. It further examines the integration of these nano-delivery systems into dairy matrices (milk, yogurt, cheese), highlighting key interactions between nanoemulsion droplets and native dairy constituents such as casein micelles and whey proteins. Critically, findings indicate that nanoencapsulation not only enhances curcumin’s solubility but also protects it from chemical degradation during industrial processes, including pasteurization and sterilization. Moreover, the dairy matrix structure plays a key role in modulating curcumin bioaccessibility, with fortified products frequently exhibiting enhanced stability, shelf life, and sensory attributes. Finally, key technological challenges addressed the heterogeneous global regulatory landscape surrounding biopolymers and future trends: most notably, the growing shift toward “clean-label” biopolymer-based delivery systems.