The modification of β-conglycinin by Polygonatum sibiricum polysaccharide through covalent and non-covalent...

The interaction between proteins and polysaccharides is crucial for applying protein-polysaccharide complexes within the food sector. This study investigated the mechanism of non-covalent and covalent interactions between β-conglycinin(β-CG) and Polygonatum sibiricum polysaccharide (PSP) and their effects on processing properties. It was observed that the addition of PSP resulted in a looser and more disordered secondary structure of β-CG, with a significant increase in α-helices, random coil and a decrease in β-sheet and β-turn. The internal structure of β-CG is opened, and its hydrophobic groups are exposed to a polar environment, showing a weakening of surface hydrophobicity and a decrease in solubility. These changes have also led to increased emulsification and foaming capacity. In addition, Non-covalent complexes have more hydrogen bonds. Covalent complexes have more hydrophobic interactions and more stable structures. When the PSP concentration reached 10 mg/mL, the covalent complex (C3) demonstrated the highest solubility (55.77 ± 0.78 %), emulsifying capacity (35.05 ± 2.69 %), and foaming capacity (106.10 ± 2.01 %). These views provide a theoretical foundation for the application of β-CG-PSP complexes in the food industry.