3D Printing with Marine Gelatin: A Cross-Sector Review of Biomedical, Food, and Health Uses.

Gelatin is a valuable hydrocolloid produced by partial hydrolysis of collagen from mainly mammalian and fish sources. The rheological properties of fish gelatin differ from those of mammalian species in terms of gel strength, viscosity, and other rheological characteristics, even from different fish species and parts of the fish with different properties. Fish gelatin is sustainable for the environment and easy for people to accept for cultural reasons. Owing to these properties, gelatin is used across food, biomedical, pharmaceutical, and health sectors, where 3D printing enables customization and functional performance. Key determinants of print fidelity include gelatin concentration, rheological properties, temperature, gelling behavior, water content, and printing parameters. Suitability for 3D printing is typically assessed via physicochemical characterization, particularly rheology and gelling mechanisms/kinetics. Gelatin-based 3D printing systems offer various advantages due to their biocompatibility, low cost, and controllable rheological properties, and they have potential applications in the food, healthcare, biomedical, tissue engineering, and drug delivery system areas. Using gelatin in combination with other additives can improve printing accuracy and mechanical strength parameters, overcome the limitations of gelatin's inherent mechanical strength, and develop higher printing accuracy and performance systems. This allows for the development of functional, innovative, and high-value-added products while ensuring safe use.