Wheat‐Based Inks With Pea Protein Incorporation for 3D Printing Free of Flow Enhancers and Stabilizers: Effects on Rheological Properties and Printing Fidelity

Knowledge of how protein incorporation affects the rheological behavior of plant‐based, high‐protein food inks and their 3D printing fidelity remains limited, especially in the absence of flow enhancers and stabilizers that typically mask the individual contributions of core components. This study establishes quantitative relationships between ink composition, rheological properties, and printing performance in wheat–pea protein ink systems. Pea protein isolate (PPI) was incorporated into wheat flour (WF)‐based inks across a range of water contents (45%–65%), with PPI replacing WF on a dry‐mass basis (PPI:WF ratios ranging from 0:100–35:65). Increasing the PPI:WF ratio increased the viscoelastic modulus and post‐shear viscosity, enhancing self‐supporting capacity but reducing viscosity recovery post‐shear. At elevated temperatures (from 20°C to 50°C), a significant increase in the loss factor (tan δ ) reduced the fidelity of 3D printing, indicating the temperature dependency of WF‐PPI inks. The highest 3D printing fidelity was achieved at 20°C with a 25% PPI incorporation and a water content of 50% of the total mass. These findings demonstrate that the 3D printing fidelity of high‐protein inks is governed by a combination of viscoelastic, shear‐recovery, and thermal response properties. The absence of flow enhancers and stabilizers further provides a well‐defined model system for discovering the contributions of individual protein and carbohydrate components to ink rheology and printability.