Optimization of Formulation and Processing Parameters for High-Fidelity 3D Printing of a Surimi–Flour Composite Batter

To enable the formulation design of 3D-printable surimi-based food systems, a surimi–flour composite batter was developed, and its printing parameters and formulation were systematically optimized using a food 3D printer, with a focus on printing accuracy, structural stability, and extrusion performance. The optimal printing parameters were identified as a flow rate of 50 mm/s, mixing time of 5 min, and syringe barrel volume of 100 mL, while the optimal formulation consisted of 25% surimi (based on flour weight), 65% water (based on total surimi–flour–water mass), and 6% butter (based on total formulation mass). Physicochemical and rheological analyses suggested that surimi promoted the transformation of bound water into immobilized water, thereby enhancing structural stability and interlayer adhesion of the printed constructs. Appropriate water addition improved hydration and extrudability, whereas butter enhanced viscoelastic properties and printing uniformity, likely through interfacial lubrication. These components collectively influenced the formation of a homogeneous gel network with pronounced shear-thinning behavior, which is essential for high-precision 3D printing. Overall, the integrated optimization of processing parameters and formulation enabled high-fidelity 3D printing of the surimi–flour composite batter, providing a formulation and processing reference for improving the printability of surimi-based composite systems in extrusion-based 3D food printing.