Effects of Oil Content and Protein Particle Concentration on Characteristics and 3D Printing Properties of High Internal Phase Pickering Emulsions

In this study, high internal phase Pickering emulsions (HIPPEs) were prepared using soybean isolate protein microgel particles, which were prepared by gel disruption, as a stabilizer. Confocal laser scanning microscopy (CLSM) showed that the oil droplets were encapsulated within protein particles, and some of them were observed to exhibit a polyhedral morphology due to stacking, which is a typical feature of typical O/W-type HIPPEs. Increasing oil content and protein particle concentration improved the viscosity, storage modulus and gel strength of the system, which endowed the emulsion with 3D printing ability. When the oil content was 75% and the protein particle concentration was 3.0%, the accuracy and stability of the printed model were 93.35% and 98.72%, respectively. The results of this study indicated that HIPPEs can be used as an effective ink for 3D printing of food products, which provide a theoretical basis for expanding the application of 3D printing in the food field.