Designing ferulic acid-functionalized dual protein conjugates: Process-induced changes, structural interplays, and sustainable calcium fortification

This study investigates the structural changes and covalent interactions of rice glutelin and egg white proteins with ferulic acid, considering the effects of germination and whisking times. Using ternary phase diagrams, we analyzed the antioxidant properties and in vitro digestive behaviors of these protein-ferulic acid conjugates. Increased germination time enhanced the conjugate potential of rice glutelin, while prolonged whisking time increased the molecular flexibility of egg white proteins. The optimal ratio of rice glutelin to egg white proteins (6:4) resulted in higher surface hydrophobicity. In vitro digestion showed that a higher proportion of rice glutelin aids gastric digestion, while more egg white protein supports intestinal hydrolysis. Extended germination time reduced particle size and antioxidant capacities during digestion but negatively impacted calcium loading from eggshells. These findings highlight the potential of tailored protein-ferulic acid conjugates for improved functional properties and food applications.