摘要
CMC incorporation induced protein unfolding and hydrophobic group exposure. • CMC grafting increased T d from 97.17 to 109.08 °C. • The ratio of PPI–GA to CMC of 1:1 showed optimal interfacial rearrangement and stability. • QCM-D confirmed the conjugate formed a thick, hydrated and strong interfacial layer. Protein–polyphenol–polysaccharide ternary conjugates represent a promising class of high-efficiency emulsifiers. However, their assembly behavior and stabilization mechanism at the oil–water interface has not yet been systematically clarified. In this study, sodium carboxymethyl cellulose (CMC) was covalently grafted onto potato protein isolate–gallic acid (PPI–GA) conjugate by dry-heating Maillard reaction, and the structural evolution and interfacial functional mechanisms of the resulting conjugates were systematically investigated. The structural characteristics of the conjugates were characterized by SDS-PAGE, fluorescence spectroscopy, FT-IR spectroscopy, circular dichroism, and scanning electron microscopy. The results showed that CMC was successfully introduced by Maillard glycosylation, which significantly altered the secondary structure and micromorphology of PPI–GA conjugate. Consequently, the emulsifying properties, surface hydrophobicity and thermal stability were improved, with the denaturation temperature reaching 109.08 °C. The PPI–GA–CMC conjugate prepared at a 1:1 mass ratio of PPI–GA to CMC exhibited optimal interfacial performance with the highest rearrangement rate ( K r = 16.33 s −1 ) and formed the most stable elastic interfacial film (ΔE/π = 2.548), and a thick, highly hydrated, and mechanically robust interfacial layer (ΔF = −36.62 Hz, ΔD = 22.52 × 10 −6 ) was formed, verified by quartz crystal microbalance with dissipation (QCM-D) analysis. These superior interfacial properties may provide a theoretical basis for designing high-performance plant protein-based emulsifiers. Download: Download high-res image (303KB) Download: Download full-size image
危险品化学品经营许可证（带存储）