Hot melt extrusion with low-temperature deposition-coupling control improves the 3D printing accuracy of gelatin/fish pulp recombinant products

Abstract

The flow properties of original materials directly affect the shape customization of 3D printing. In order to improve the molding quality, the 3D printing equipment was developed, which was characterized by a variable pressure and temperature extrusion unit, a numerical control transmission unit, an extrusion refrigeration unit, and a control box. The optimal pretreatment condition of sturgeon skin was 0.015 M phosphoric acid with higher gel strength (739.27 g), which could be a good substitute for commercial gelatin. The 7% gelatin/fish pulp reconstituted system could exhibit optimum printing properties through an improved 3D printer. The reconstituted system displayed a smoother printing process and superior accuracy during the process of 3D printing, and showed higher apparent viscosity and modulus during the process of cooling and molding. Additionally, the network structure of 3D printing products of reconstituted the gelatin/fish pulp was denser, which showed higher water holding capacity (89.03%), higher hardness (775.64 g), and constant elasticity (0.9853).