Flavor and structure characteristics of egg white peptides based on γ-glutamylation modification: A promising flavor enhancement strategy.

The widespread use of egg white peptides (EWP) in healthy foods is limited by undesirable flavors. In this study, transglutaminase (TG) was used to catalyze the γ-glutamylation reaction between glutamine (Gln) and EWP, modifying the structure and flavor of EWP. The interaction of Gln and EWP altered the primary structure and spatial conformation of EWP, thus increasing the solubility. γ-glutamylation reduced the bitterness and increased umami of EWP by consuming hydrophobic bitter amino acids and generating umami peptides. Twenty-one synthesized γ-glutamyl peptides were identified in G-EWP after γ-glutamylation, which could enhance the sweetness, saltiness, umami, and kokumi taste of basic substances. All of these peptides could enter the Venus flytrap (VFT) of calcium-sensing receptor (CaSR), which might be the mechanism of G-EWP with enhanced kokumi taste. Overall, this research provided the theoretical basis for flavor improvement of EWP.