3D Printing of Unconventional Starches from Andean Tubers: Microstructural, Textural, and Rheological Properties

Abstract This study evaluated the potential of unconventional starches extracted from Andean tubers, ulluco (Ullucus tuberosus) and cubio (Tropaeolum tuberosum), as raw materials for 3D food printing. Gels were formulated with starch concentrations of 8%, 10%, and 12% (w/v) and characterized in terms of microstructure and rheological properties. Both starches exhibited suitable printability, attributed to their pseudoplastic flow behavior. However, the hardness of the printed structures varied depending on starch type and concentration. Cubio starch showed higher hardness at both low and high concentrations (8% and 12%), whereas ulluco starch exhibited its highest hardness at the lowest concentration. Microscopic analysis revealed reticulated networks whose homogeneity was influenced by the degree of gelatinization and the starch content in the matrix. The printed gels demonstrated good resilience, variable hardness, and low crystallinity, indicating thermal-induced disruption of the native ordered structure. Rheologically, the samples showed viscoelastic behavior dominated by the elastic modulus ( G’ ) and fitted the power-law model. These findings support the technological feasibility of ulluco and cubio starches as functional ingredients for the development of customized or functional foods through additive manufacturing technologies. Their application may foster the utilization of underused crops and contribute to the diversification of raw materials in the food industry.