Abstract: This study aimed to investigate the effects of different concentrations of Auricularia auricula polysaccharides (AAP) on the properties and 3D printing performance of corn starch (CS) gels loaded with tea polyphenols (TP). The rheological properties, water distribution, intermolecular interactions, microstructure, textural properties, printing accuracy, color, and antioxidant activity of AAP-CS composite gels were measured to analyze the feasibility of applying these gels as 3D printing materials for food development. The results indicated that AAP load significantly affected the structural characteristics and 3D printing performance of composite gels, with the 3D printing performance initially increasing and then decreasing as the AAP load increased. A favorable equilibrium was established between the dynamic rheological behavior (storage modulus and loss modulus) and the steady-state rheological behavior of the composite gel loaded with 1 g/100 mL of AAP. Meanwhile, the gel exhibited higher hardness, chewiness, and adhesiveness, as well as a denser microstructure, demonstrating the best 3D printing performance. Fourier transform infrared (FTIR) spectroscopic analysis indicated that AAP interacted with CS and TP in the composite gel primarily via hydrogen bonding, without forming new chemical bonds. Furthermore, as the concentration of AAP increased, the color of gels became gradually deeper, the free radical scavenging capacity rose, and the antioxidant capacity increased. The combined addition of polysaccharides and polyphenols significantly improved the 3D printing properties of starch-based materials, providing a reference for the development and application of 3D-printed foods.

Key words: Auricularia auricula polysaccharides; corn starch; tea polyphenols; composite gels; 3D printing