Characteristics and functional properties of soybean peptides-Hawthorn pectin Maillard conjugates synthesized/obtained under controlled temperature conditions.

In the study, soybean peptide-Hawthorn pectin Maillard conjugates (SBP-HP-MC) were first obtained through the Maillard reaction at different temperature (50 °C, 70 °C, 90 °C) and were investigated using a series of characterization methods. UV, Intrinsic fluorescence, Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and Fourier transform infrared spectroscopy (FT-IR) analyses confirmed that SBP and hawthorn pectin (HP) formed high-molecular-weight conjugates. The results demonstrated that the degree of the grafting (DG) (43.37 ± 0.05 % to 49.53 ± 0.05 %) of the product exhibited an initial increase with rising temperature. The conjugation of HP significantly enhanced the gelling ability, rheological properties (viscosity up to 301.68 mPa· s), emulsifying activity (14.79-28.09 m/g), and antioxidant capacity (53.04-72.31 %) of soybean peptides (SBP). Notably, these improvements were positively correlated with the DG. Texture analysis indicated an increase in hardness (up to 3085.16 ± 2.08 N/m), cohesiveness, and adhesiveness in SBP-HP-MC/Ca complex gels at 12.5 %. Furthermore, the liquid viscosity (Viscosity at 50 1/S of 10 % SBP-HP-MC70: 301.68 ± 0.32 mPa·s) of SBP-HP-MC varied from "nectar type" (51-350 mPa·s) to "honey type" (351-1750 mPa·s). SBP-HP-MC demonstrates significant potential as a texture modifier in the food industry.