Pickering emulsion stabilized by zein/Adzuki bean seed coat polyphenol nanoparticles to enhance the stability and bioaccessibility of astaxanthin

The objective of this study was to explore the physicochemical stability and in vitro digestibility of astaxanthin (AST)-loaded Pickering emulsions stabilized by zein and Adzuki bean seed coat polyphenol (ABSCP) covalent nanoparticles. Compared to zein-alone stabilized Pickering emulsion (ZE), ABSCP fabrication improved the Pickering emulsion (ZAE) against the ionic strength and high-temperature treatment. Furthermore, the ratio of AST remaining in ZAE after exposure to high levels of UV light irradiation was higher than 90%. Due to the change in electrostatic repulsion during in vitro digestion, droplet size, zeta potential, and microstructure of ZAE changed. More importantly, the bioaccessibility of AST reached up to 58.56% +/- 0.89% and 55.66% +/- 1.48% for ZE and ZAE, respectively. The results indicate that ZAE may be an effective delivery system for AST or other hydrophobic bioactive compounds. This study may contribute to the protection and delivery of AST and the development of novel functional foods.

Automated summary

This study demonstrated that the AST-loaded Pickering emulsion stabilized by a combination of zein and Adzuki bean seed coat polyphenol had improved stability against high ionic strength and temperature treatments, with a high remaining ratio of AST after UV light exposure. The in vitro digestion process led to changes in droplet size, zeta potential, and microstructure of the emulsion, resulting in high bioaccessibility of AST. These findings suggest that this system may be effective for delivering AST and other hydrophobic bioactive compounds, contributing to the development of novel functional foods.