3D printing of curcumin enriched Pickering emulsion gel stablized by pea protein-carrageenan complexes

3D printable Pickering emulsion (PE) gel containing curcumin (CCM) was produced stablized by pea protein isolate (PPI)/k-carrageenan (KG) complex particles. The PPI/KG complexes were characterized, with changes observed in their zeta potential, particle size, and secondary structure of PPI upon the addition of KG. The resulting PE gel was created with 75% oil fraction, 5% PPI, and 0.1%–0.5% KG of the aqueous phase. Confocal laser scanning microscope (CLSM) suggested that the oil droplets were surrounded by the PPI/KG particles, and their size decreased with increasing KG concentration. Furthermore, the addition of KG improved the strength and viscosity of the PE gel. 3D printing tests demonstrated that the PE gel with KG concentrations greater than 0.3% displayed smooth extrusion and excellent self-supporting capability, effectively maintaining the desired shape structure. Additionally, the incorporation of KG improved the encapsulation efficiency of CCM, enhancing its stability. It would be interesting to use pea protein stablized PE gel as an ink for 3D printing to create potential cake surface decoration.