Whole cereal protein-based Pickering emulsions prepared by zein-gliadin complex particles

Zein and gliadin are both cereal proteins, indicating that they are highly compatible. In this study, gliadin was firstly added to zein to achieve different zein/gliadin ratios in aqueous ethanol solution, then we synthesized zein-gliadin complex particles (ZGCP) via an antisolvent approach and investigated their efficiency as stabilizers to fabricate Pickering emulsions. The addition of gliadin affected the self-assembly, aggregation and wettability of ZGCP. Scanning electron microscope (SEM) showed that spherical zein particles were transformed into aggregation of nano-sized ZGCP, and FTIR results indicated that weak flocculation behavior of ZGCP involved in intermolecular beta-sheet interactions. Furthermore, relatively hydrophilic gliadin was used to modify the hydrophobic property of zein, resulting in formation of near-neutral wettability of ZGCP. Compared with zein or gliadin, ZGCP tend to form a dense interfacial layer around droplet and smaller emulsion droplet size, endowing ZGCP-stabilized emulsions with higher viscoelastic attributes and much better stability against coalescence. This finding may develop theoretical and technical supports for the utilization of the whole cereal protein-based Pickering emulsions as novel natural ingredients in food industry.