Effect of rheological properties of potato, rice and corn starches on their hot-extrusion 3D printing behaviors

In this study, the relationship between rheological properties and printability of three types of starch (potato rice and corn starch) for hot-extrusion 3D printing (HE-3DP) were systematically investigated. Each starct sample showed a shear-thinning behavior, self-supporting property, as well as the feature of a substantial de crease at higher strains and a recovery at lower strains in storage modulus (G'), which indicated the suitability o starch for HE-3DP. Besides, the flow stress (tau(f)), yield stress (tau(y)), and G' increased with a higher starch con centration. We found that starch suspensions with concentrations of 15-25% (w/w) heated to 70-85 degrees C possessed preferable values of tau(f) (140-722 Pa), tau(y) (32-455 Pa), and G' (1150-6909 Pa) for HE-3DP, which endowec them with excellent extrusion processability and sufficient mechanical integrity to achieve high resolution; (0.804-1.024 mm line width). Overall, our results provided useful information to produce individualized starch based food by HE-3DP.