Protein source and redox-mediated structural modifications, bioactivity, and celiac-related peptides in high-moisture extruded gluten-based meat analogs.

This study examined how protein source and redox treatment influence structural properties and peptide profiles of high-moisture extruded (HME) meat analogs. Wheat gluten (WG) was blended with soy protein (SP) or pea protein (PP) and L-cysteine/ascorbic acid (LC/AA) followed by HME. The optimum feed moisture content (FMC) was selected based on the degree of texturization, which was subsequently analyzed for structural, thermal, digestibility, bioactivity, and celiac-related peptide. WG-SP formed stronger β-sheet-rich networks, whereas WG-PP showed more molecular flexibility with higher β-turn and random coil. LC/AA treatment promoted intermolecular disulfide bond rearrangement and re-polymerization, resulting in increased β-sheet formation, a higher denaturation temperature, and improved hardness. Peptide analysis revealed that WG-PP produced more predicted bioactive peptides and fewer celiac-related epitopes than WG-SP. The immuno-dominant 33-mer celiac-related peptide was detected only in WG-SP. Overall, structural strengthening through redox-mediated modification did not sufficiently reduce potential celiac-related risks in WG-based meat analogs.