Interpenetrating network emulsion gels prepared from polysaccharides and pea proteins: effect of polysaccharide charge on rheology, freeze-thaw stability, and dysphagia characteristics.
Interpenetrating network emulsion gels were fabricated from pea protein isolate (PPI) and polysaccharides with different charges: anionic Artemisia sphaerocephala Krasch gum (ASKG) or neutral curdlan (CURD). Microstructure, molecular interactions, rheology, texture, water holding capacity (WHC), cooking properties, and freeze-thaw stability were characterized. PPI-ASKG reduced oil droplet size compared to PPI-CURD. Polysaccharides modulated protein secondary structure, with hydrophobic attraction and hydrogen bonding as dominant intermolecular forces. The PPI-ASKG gels formed a thicker oil-water interfacial layer, contributing to superior viscoelasticity, WHC, and cooking performance. A preferred formulation with 0.3 wt% ASKG (A3) displayed the highest Q fator (23.62), thixotropic recovery rate (90.50%), strain-stiffening/thickening indices, and lowest freeze-thaw syneresis (22.4%), well-preserved texture and a reduced freezing point of -19.05 °C. All emulsion gels with 0.2-0.4 wt% polysaccharides met International Dysphagia Diet Standardization Initiative Level 5 criteria. This work provides a scientific basis for developing plant-based dysphagia-targeted foods with excellent freeze-thaw stability.