Rheological properties and 3D printability of tomato-starch paste with different types of starch

In this study, the effect of different types of starch additives on the quality of three-dimensional (3D) printed food products containing tomato-starch paste (TSP) was investigated. The printability of TSP was evaluated by examining its rheological and textural properties and the microstructure of 3D printed products. The results indicated that the TSP containing wheat starch exhibited the best printing accuracy and print quality than the other samples. The macrorheological and microrheological analysis results showed that the apparent viscosity, loss modulus, storage modulus, and viscoelasticity of the TSP containing wheat starch were significantly higher than those of the other samples (P < 0.05). Low-field nuclear magnetic resonance (LF-NMR) results showed that T21 and T22 of TSP containing wheat starch significantly decreased, thereby improving the retention of printed shapes and deposition of 3D-printed TSP. The analysis of textural properties showed that the TSP containing wheat starch had significantly higher strength of hardness, springiness, cohesion, and chewiness (P < 0.05). Thus, the pseudoplastic gel formed by TSP containing wheat starch exhibited a higher fluidity and structural density than the other samples, which improved the extrudability and shape stability of the printed product as well as the self-supporting properties of TSP.