Fabrication, characterization, and application in 3D printing of high internal phase emulsion stabilized by alkaline thermal treated pea protein and pectin complex.

Alkaline thermally treated pea protein and pectin complex was utilized to create high internal phase emulsions (HIPE) for extrusion-based 3D printing. Pea protein heated at pH 10 and 100 °C was optimized and chosen based on criteria such as solubility, surface hydrophobicity, particle size, and surface charge. The most promising ink for 3D printing was selected from HIPE stabilized by complexes containing 2 % heated pea protein with varying pectin concentrations (0.25 % ∼ 1 %) and pH levels (3-7). The complex containing 1 % pectin at pH 7 endowed the emulsions with favorable rheological properties and particle size, as well as excellent heat resistance and storage stability. The optimized HIPE formulation was successfully used for 3D printing, resulting in printed shapes exhibiting robust self-supporting characteristics. Data indicated that the combination of alkaline thermally treated pea protein and pectin could serve as an excellent emulsifier for constructing HIPE, suitable for applications in 3D printing within the food industry.