Abstract: In this study, the effect of dynamic high pressure microfluidization at different pressures on the structural and functional properties of pea albumin and its complex with chlorogenic acid was investigated by measuring particle size, zeta potential, fluorescence spectra, infrared spectra, hydrophobicity, solubility and emulsification properties. The mechanism of the influence of chlorogenic acid on pea albumin in the binary system was explored. The results showed that after dynamic high pressure microfluidization treatment, the particle size and zeta potential of pea albumin firstly decreased and then increased. The microstructure, secondary structure and tertiary structure of pea albumin were changed. The solubility of small pea albumin particles was significantly increased by 42.37%, reaching 0.84 mg/mL under the action of shear force and other effects (P < 0.05), and the emulsification characteristics were also enhanced. The addition of chlorogenic acid changed the microenvironment of tryptophan residues in pea albumin, which led to significant changes in the structure of pea albumin. Meanwhile, it significantly increased the surface hydrophobicity and decreased the solubility of pea albumin (P < 0.05), and improved the solubility. This study provides an idea for pea albumin modification and a theoretical foundation for the development of high-value protein products.

Key words: dynamic high pressure microfluidization; pea albumin; chlorogenic acid; physical modification