Mechanistic insights into water-state-mediated consolidation and texture development in butter–whey protein fortified potato starch 3D-printed foods

, suggesting facilitated starch hydration, intensified protein-lipid-starch interactions and strengthened high-temperature network consolidation. SEM confirmed that formulations with optimized water states developed more continuous and compact microstructures. These molecular and structural features manifested as higher hardness, elasticity and slower stress relaxation in C7. Correlation analysis linked water-state parameters to thermal transitions, microstructural organization and viscoelastic-textural responses, demonstrating that water binding and mobility play a central physicochemical role in matrix assembly. These findings establish a water-state-mediated mechanism governing the functionality of butter-whey protein fortified starch-based 3D printing inks.