Regulate the interfacial characteristic of emulsions by casein/butyrylated dextrin nanoparticles and chitosan based on ultrasound-assisted homogenization: Fabrication and characterization

In the work, bilayer emulsions stabilized by casein/butyrylated dextrin nanoparticles (CDNP) and chitosan (CS) were prepared based on ultrasound-assisted homogenization. The effects of different homogeneous pressures and various CS concentrations on physical properties and microstructures of bilayer emulsions were investigated. The homogenization condition of 80 MPa was selected to prepare emulsions due to the fact that the emulsion showed the best stability under this condition. Compared with the monolayer emulsion, the bilayer emulsions showed excellent stability (storage, pH, and freeze-thaw cycle) due to the unique interface structure based on composite bilayer interface of CDNP and CS. Meanwhile, the results of optical microscopy, transmission electron microscopy, and confocal laser scanning microscopy showed that emulsion droplets evenly distributed and were cross-linked by CS chains to form a network structure in bilayer emulsions. These results would provide a new insight for the development of bilayer emulsions based on composite interface and bilayer interface. • The layer-by-layer electrostatic deposition was used to prepare bilayer emulsions. • The emulsion droplets were cross-linked by CS chains to form a network. • The bilayer emulsions showed excellent stability. • The bilayer emulsions based on composite interface and bilayer interface.