Formulation and Characterization of Natural Surfactant-Stabilized Zein Nanoparticles for Encapsulation of Ergocalciferol

Ergocalciferol, despite its high beneficial potential in foods and pharmaceuticals, faces challenges in utilization due to its hydrophobic and sensitive properties. In this study, we developed ergocalciferol-loaded zein nanoparticles coated with modified lecithin (ML) or rhamnolipids (RL) using the anti-solvent precipitation method. Both ML- and RL-stabilized zein nanoparticles exhibited narrow particle size distribution and high encapsulation efficiency of ergocalciferol, achieving 94.54 ± 2.28% and 94.24 ± 2.35%, respectively. The ML-stabilized nanoparticles demonstrated good stability under thermal treatments (30–90 °C) and pH variations (pH 3–8). In comparison, the nanoparticles stabilized by rhamnolipid (RL) remained stable under thermal conditions but became unstable when the pH dropped below 6. Additionally, both ML- and RL-stabilized nanoparticles demonstrated an increase in particle size after the addition of salt. Furthermore, all samples displayed high bioaccessibility of ergocalciferol after in vitro digestion and excellent physicochemical stability during 30 days of storage. Therefore, the ML- and RL-stabilized zein nanoparticles present promising prospects for effectively transporting functional ingredients such as ergocalciferol.