Complexation, Molecular Forces, Digestibility, and Celiac–Related Peptides of Gluten Blend Meat Analogs with Redox Agents

Improving the compatibility of wheat gluten (WG) with other plant proteins is essential for modifying texture and reducing celiac-related peptides in plant‐based meat analogs. This study examined the effects of incorporating soy protein (SP) and pea protein (PP) into WG formulations, using L‐cysteine (LC) and ascorbic acid (AA) as redox‐modulating agents. Protein-protein interactions, including hydrogen bonding, hydrophobic interactions, disulfide bonding, and sulfhydryl content, were analyzed. Peptides generated from in vitro digestion were identified by LC-MS/MS, and potential celiac‐related peptides were predicted from identified sequences using a relevant epitope database. Heating induced protein aggregation through disulfide and non-covalent bonds, masking protease cleavage sites and lowering digestibility. Substitution with SP or PP enhanced bond formation, dominated by non-covalent interactions. The addition of LC/AA improved dough extensibility and surface smoothness after heating. Protein band analysis revealed glycinin and legumin polymerization, while α‐gliadin bands disappeared, indicating formation of insoluble high‐molecular‐weight aggregates. LC/AA did not substantially alter overall protein patterns but reduced gliadin solubility upon heating. Peptidomic analysis showed that WG-SP and WG-PP reduced the number of celiac‐related peptides, whereas LC/AA increased peptide length and epitope frequency, particularly in WG-PP-LC/AA samples. Highly immunogenic DQ2.5‐restricted epitopes remained prevalent, with WG-SP showing the lowest abundance. Overall, these findings demonstrate that protein source, structural modification, and redox chemistry jointly influence the textural and immunogenic properties of meat analogs, offering strategies for developing safer and more functional plant‐based alternatives.