Improvement mechanism of cellulose nanocrystal in coordination with calcium ions on the thermal gelation of soybean protein amyloid fibrils

This study investigated the mechanism by which cellulose nanocrystals (CNC) derived from pear peel pomace synergize with Ca²⁺ to regulate the thermal gelation of soy protein amyloid fibrils (SAFs). Results showed that the combined use of 0.09 % (<i>w</i>/<i>v</i>) CNC and 400 mmol Ca²⁺ significantly enhanced SAFs gel strength and viscoelasticity, promoting the formation of β-sheet conformation and exposure of aromatic amino acid residues in SAFs. CNC reinforced hydrogen bonds to form excellent water-holding gel units, whereas Ca²⁺ strengthened ionic bonds and hydrophobic interactions to construct low water-holding gels with high strength. Mechanistic analysis revealed that CNC binds to specific SAFs amino acid sites via van der Waals forces and hydrogen bonds, while Ca²⁺ enhances CNC-SAFs crosslinking through electrostatic shielding effects. This study's new insights into the synergistic regulation of polysaccharide ions in SAFs gels could be applied to functional gel foods with controllable gel strength and WHC properties.