Structure, interfacial adsorption and emulsifying properties of potato protein isolate modified by chitosan

Abstract

In this study, the relations among the structure, interface adsorption and emulsifying properties of potato protein isolate (PPI) modified by chitosan (CS) were investigated. The results showed that the addition of CS prevented the exposure of tyrosine and tryptophan residues, leading to an increase in the surface hydrophilicity of PPI in the complex system. Meanwhile, the addition of CS decreased the interfacial tension between oil-water and gas-water, and increased the elastic modulus (G′) and the apparent viscosity of PPI in the complex system. Moreover, the emulsion stabilized by the PPI/CS complex exhibited a smaller average particle size and a higher zeta - potential with a better emulsifying stability. In addition, the gel network structure of the emulsion stabilized by PPI/CS complex enhanced to promote the emulsion stability. These results will provide meaningful guidance for the application of CS modified PPI as a novel food emulsifier in the construction of stable Pickering emulsion system.