Self-assembly mechanisms of wheat gluten peptides: Modulating interfacial behavior and foaming properties

Foam performance plays a critical role in food systems by influencing texture and stability. This study investigates how the self-assembly of wheat gluten protein peptides (WGPs) affects foaming behavior and interfacial properties. Self-assembled WGP gel nanoparticles (WGPM-NPs, 3-10 kDa) produced interfacial layers with higher interfacial expansion viscoelastic modulus (E) and elastic sub-modulus (E_d), resulting in enhanced foaming capacity (128.3 ± 22.3 %) and foam stability (39.1 ± 3.3 %). The interfacial layers stabilized by WGPM-NPs also exhibited increased composite modulus and strain-hardening behavior during expansion and compression, forming a highly elastic, solid-like two-dimensional gel interface that combines rigidity and flexibility. These characteristics contributed to improved long-term foam stability. Overall, the findings demonstrate that leveraging WGP self-assembly is an effective strategy to improve foam performance and regulate interfacial behavior, offering new insights into the application of self-assembled peptide gel nanoparticles in functional food systems.