ATGL modulates lipid-protein interactions to restore foaming capacity in yolk-residue egg white systems

Residual egg yolk in egg white, a common issue in industrial processing, impairs foaming properties vital for aerated bakery products. This study reveals that yolk residue ≥0.7 % (w/w) destabilizes foams via lipid bridge formation and interfacial protein network disruption. Enzymatic strategies using adipose triglyceride lipase (ATGL) and a commercial enzyme (CE) were compared to restore functionality. ATGL treatment (1000 U/g, 45 °C, 2 h) hydrolyzed triglycerides into free fatty acids, increasing glycerol content by 258.6 % (0.29 % to 1.04 %), eliminating lipid interference and restoring foaming ability (FA) close to fresh egg white levelis, while foaming stability (FS) was fully restored. Structural analyses (SDS-PAGE, confocal laser-scanning microscopy) confirmed ATGL preserved native egg white proteins, whereas CE hydrolyzed ovomucin, altering protein solubility. Cakes prepared with ATGL-treated egg whites exhibited desirable texture (hardness 388.61, springiness1.41, chewiness 459.49, resilience 0.53) comparable to fresh controls, surpassing CE-treated samples. This work elucidates lipid-protein interaction mechanisms in yolk-residue systems and establishes ATGL as a targeted biocatalyst for egg white functionality recovery. The findings offer a sustainable solution for optimizing egg processing, with direct applications in bakery industries reliant on foam-based matrices.