Peptides-carrageenan-xanthan gum: Printing mechanism and anti-oxidation under in vitro digestion

Surimi is a protein-rich food. The peptides hydrolyzed by surimi have many functional activities and showed strong antioxidant activity in ABTS free radical scavenging experiments, hydroxyl radical scavenging experiments and iron ion reduction experiments. The scavenging rates of ABTS ions, hydroxyl radicals and iron ions were 62.83%, 74.81% and 0.035 mg/mL, respectively. 3D printing ink was formulated by compounding carrageenan, xanthan gum and surimi peptides. The surimi polypeptide “ink” contains 3% carrageenan, 4% xanthan gum and 4 mg/mL surimi polypeptide. This “ink” not only has good printability, but also has stable antioxidant properties. The effect of the peptides on the printed structures can also be observed under an inverted fluorescence microscope. In the in vitro digestion experiment, the surimi polypeptide 3D printing ink added with carrageenan and xanthan gum can release most of the peptides. After in vitro digestion experiments, the antioxidant activity of surimi polypeptides increased. The above experiments have proved that surimi polypeptide is a high-quality raw material for preparing 3D printing ink.