An innovative germination-driven LAB fermentation strategy for allergenicity reduction in soymilk gels through spatiotemporal protease-mediated epitope disruption.

This study innovatively integrated seed germination (1-3 days) with LAB fermentation to establish a structure-immunomodulation nexus in fermented soymilk gels. Germination degraded hydrophobic proteins, forming soft gels with substantially reduced hardness and improved water-holding capacity, alongside refined porous networks. Structural loosening enabled LAB proteases to access core allergenic domains, cleaving β-barrel (e.g., Gly m 5.03, residues 134-164) and α-helix clusters (e.g., Gly m 5.02, residues 118-124). This synergistic proteolysis reduced IgE-binding and antigenicity by over 40% compared to the FSM gel. Peptidomics revealed a continuous degradation process: surface epitopes (e.g., Gly m TI, residues 92-101) were predominantly degraded during days 1-2, whereas interior IgE-binding regions (e.g., Gly m Bd 30K, residues 202-209) became increasingly cleaved by day 3. The germination-fermentation cascade synergistically reconfigured protein matrices via hierarchical proteolysis, linking the porous gel architecture with immunoreactivity suppression. This dual bioprocessing strategy bridges texture engineering and allergen inactivation, offering a structure-guided approach for developing hypoallergenic plant-based foods.