Dual-Polysaccharide Reinforced Pickering Emulsion Gels for Tailoring Microstructure and Enhancing 3D Printing Performance

Three-dimensional (3D) food printing enables personalized fabrication but requires materials with suitable printing properties. This study developed high internal phase Pickering emulsions (HIPPEs) stabilized by co-assembled whey protein isolate (WPI) with κ-carrageenan (κ-CA) in a binary system and with both κ-CA and curdlan gum (CG) in a ternary system. The aim was to clarify the distinct roles of anionic and neutral polysaccharides in regulating emulsion printability. Incorporation of 1.2% κ-CA and 1.6% CG optimized the three-phase contact angles of the binary and ternary particles to 78.84 ± 0.87° and 86.22 ± 0.74°, respectively. The ternary system exhibited significantly greater oil-phase wettability (p < 0.05). Rheological and textural analyses showed that κ-CA concentration primarily governed yield stress and self-supporting capacity in the ternary system, with an optimum at 1.2%. In contrast, CG incorporation was essential for improving thixotropic recovery and printing accuracy, with an optimum at 1.6%. The optimized ternary HIPPEs exhibited excellent 3D printing accuracy with a food-grade oil phase and surpassed the binary system in structural integrity and shape fidelity. These findings clarify the distinct yet complementary roles of anionic and neutral polysaccharides in modulating HIPPEs printability and provide a rational material-design strategy for developing high-performance food 3D-printing system.