Formation, stability and the application of Pickering emulsions stabilized with OSA starch/chitosan complexes

We demonstrated the formation, structure and stability of Pickering emulsions stabilized by octenyl succinic anhydride starch (OSA-S)/chitosan (CS) complexes and explored their potential as templates for porous materials. Sufficient oil fraction (Φ > 50 %) was decisive for stable emulsions, whereas the complex concentration (c) significantly affected the gel network of emulsions. An increase in Φ or c led to tighter droplet arrangement and enhanced network, which improved the self-supporting characteristics and the stability of emulsions. The stacking of OSA-S/CS complexes at the oil-water interface influenced the emulsion properties, forming typical microstructure with small droplets embedded in interstices of large droplets, and bridging flocculation occurred. Porous materials prepared using emulsions (Φ > 75 %) as templates exhibited semi-open structures with pore size and network varying with different Φ or c. There was no structure collapse due to the interconnectivity of complexes. Our work provides comprehensive information on OSA-S/CS complex-stabilized Pickering emulsions.