Investigation and effect on 3D printing quality of surimi ink during freeze-thaw cycles by antifreeze peptides

Frozen storage of 3D printing ink is an inevitable trend, but it may impair the processing properties of surimi ink. Antifreeze peptides (AFPs) show potential application foreground in 3D printing. In this study, the rheological properties in 3D printing extrusion, recovery and stabilization stage were investigated of surimi ink with AFPs during FT cycles, and linking the printability, resolution and shape fidelity, respectively. Moreover, the evaluation method of 3D printing quality during freeze-thaw (FT) cycles including printability, resolution, and shape fidelity of surimi ink after FT was firstly established by the line of suspension and 1D patterns, 2D patterns, and 3D models. The results showed that the rheological properties of ink were significantly improved due to optimum addition of AFPs during FT cycles. The yield stress (τ₀), consistency index (K), and shear-thinning index (n), of 2% AFPs ink at FT 4 times were 185.93 Pa, 2.506 × 10⁵ Pa•sⁿ, and 0.062, respectively, in the extrusion stage. In the recovery stage, the recovery time (T) and gelation time (Tgel) were 26.14 s and 174.83 s. In the stabilization stage, the ink has properties similar to solids, the interaction strength of molecular (A) and the number of molecular interactions (z) were 1.994 × 10³ Pa s^1/z and 9.488. It demonstrated best printability, resolution, and shape fidelity, even supporting 23-layer 3D printing structures. This research firstly constructed a new approach for the application of AFPs in 3D printing of frozen foods.