Novel synergistic modulation strategy for egg white protein and pumpkin seed protein gelation: structural characteristics, swallowing functionality, and formation mechanisms.

BACKGROUND

Egg white protein (EWP) can be used to enhance the thermal gel properties of pumpkin seed protein (PSP), but the underlying molecular mechanism and potential for foods for individuals with dysphagia remain unexplored. This study aims to investigate the texture properties of PSP-EWP co-gelation.

RESULTS

Egg white protein significantly improved disulfide bond formation (from 31.74% to 41.70%) and promoted hydrophobic group folding within the composite system. These structural modifications enhanced the protein-water binding capacity, as evidenced by a 94.19% increase in bound water content, thus exhibiting marked improvements in hardness (from 27.63 to 599.72 g), springiness (from 28.32% to 87.55%), and water-holding capacity (from 16.06% to 68.04%) of the dual protein composite gel. Multiple techniques, including secondary structure analysis, fluorescence spectroscopy, particle size measurement, surface hydrophobicity assessment, atomic force microscopy (AFM), and scanning electron microscopy (SEM), collectively revealed the mechanism of dual-protein aggregate formation. These aggregated function within the gel system by enabling proteins to regulate aggregation behavior through the synergistic effects of electrostatic interactions and hydrogen bonding. Egg white protein dominated the construction of dense gel network scaffolds in the composite gels, whereas PSP hindered cross-linking through physical obstruction, resulting in a porous structure. When the PSP:EWP ratio was 8:4, 6:6, or 4:8, the International Dysphagia Dietary Standardization Initiative (IDDSI) test showed that the composite gel could be classified into six or seven grades. Such result indicated that the composite gel was suitable for people with mild dysphagia.

CONCLUSION

The results showed that the properties of PSP-EWP composite gels could be controlled by adjusting the PSP:EWP ratio, indicating the potential use in transitional foods for patients with dysphagia. © 2025 Society of Chemical Industry.