Characterization of Pickering emulsions stabilized by delipidated egg yolk granular protein nanoparticles crosslinked with ultraviolet radiation

Abstract

In this study, delipidated egg yolk proteins were used for the first time to prepare nanoparticles by the self-assembling method at pH 8.0, then treated with UV-C as a crosslinking agent, and their stability tested at pH 7.0, which is a more convenient pH for food applications. According to the results obtained, non-irradiated nanoparticles had a size of 431.8 ± 75.7 nm at pH 7.0, but the 10 min UV-C irradiated nanoparticles had an average size of 139.7 ± 5.9 nm. These nanoparticles also showed a high resistance to destabilization by SDS, urea or DTT and noticeable antioxidant and ferrous chelating activities. Pickering emulsions prepared at the nanoparticle concentration of 1 % (w/w) showed the smallest average droplet size and the lowest Turbiscan stability index value after 80 days of storage. All in all, these results have important implications for the utilisation of these proteins as a conventional Pickering emulsifying agent.

Keywords: Egg yolk protein; Emulsion microstructure; Nanoparticle; Self-assembly; Ultraviolet radiation; pH.