Effect of oat flour on the 3D printing properties of mashed potatoes: rheological, textural, and oro-sensory...

The development of printable food inks for 3D printing requires optimization of rheological and mechanical properties to balance extrusion ease with structural stability. Mashed potato (MP), a starch-based material, is commonly used as an edible ink but faces challenges such as weak gel strength and sensitivity to printing conditions. Incorporating oat flour (OF), rich in β-glucans, may enhance printability by improving ink rheology and texture, and health benefits.

Viscosity assessments revealed that MP-OF blends maintained a stable viscosity plateau between 70 and 60 °C, an optimal printing window ensuring consistent flow. Ink formulations containing 50% OF exhibited optimized viscosity and shear-thinning behavior suitable for stable extrusion and structural fidelity during printing. Printability tests demonstrated that pure OF inks lacked sufficient mechanical strength for shape retention, whereas pure MP inks exhibited dimensional distortions. MP-OF blends, especially MP-OF50, achieved improved shape fidelity and enabled printing of complex geometries with high dimensional accuracy and structural stability over time. Texture profile analyses indicated that OF addition softened gels and enhanced cohesiveness and adhesiveness, with minimal impact on consumer liking and oral processing parameters.

MP-OF formulations, particularly with 50% OF substitution, provide a balanced rheological profile suitable for extrusion-based 3D food printing. These blends overcome mechanical limitations of pure MP, allowing fabrication of structurally stable, palatable, and potentially health-enhanced 3D-printed foods. This approach supports personalized nutrition and the use of accessible, home-friendly 3D printing technologies for novel food design. © 2025 Society of Chemical Industry.