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

In this study, the effect of different types of starch (potato, wheat, corn, tapioca, and mung bean) 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 showed that the tomato starch paste containing wheat starch had the best printing accuracy and print quality compared to the other samples, which had an extruded line width of 0.93 mm and centre heights and diameters of 18.56 mm and 20.15 mm. 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 T 21 and T 22 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 TSP containing wheat starch had significantly higher strength in terms of hardness, elasticity, cohesion and chewiness, which were 9.58 N, 0.58, 0.31 and 2.13 N, respectively ( 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. • The suitable formulation enables 3D printing of tomato-starch paste (TSP). • The tomato with the addition of starch and xanthan gum forms stable gel. • The wheat starch (WS) improved the rheological behaviour of TSP. • The WS improves the 3D printability of TSP.