Improved printability of pea protein hydrolysates for protein-enriched 3D printed foods

In this study, we aim to develop a protein-enriched food ink system using a pea protein isolate (PPI) by incorporating a pea protein hydrolysate (PPH). The printability of food inks without PPH decreased as the PPI content increased from 24%, w/w to 32%, w/w. For protein-enriched 3D printed food, incorporating PPH in a food ink with PPI (24%, w/w) reduced the printing precision, which caused failure in stacking layers of printed food product. In case of a food ink system with high PPI content (32%, w/w), however, the increment of PPH content decreased viscoelastic values, resulting in improved printability. The PPH, as a hydrolyzed protein with low molecular weight and short peptide chains, prevented matrix formation in a food ink system. Thus, the hardness of the PPI food ink with PPH decreased as the PPH content increased. These results indicate that the protein hydrolysate can improve the food printing quality through the modification of the food texture even though the protein solid content in food ink increased.