A review on gelatin films and coatings for active food packaging: functional properties and applications

Gelatin, a biodegradable biopolymer sourced primarily from the collagen of mammals, fish, and poultry, exhibits promising potential in sustainable food packaging due to its antioxidant, antimicrobial, and film-forming properties. However, its practical application in food preservation is challenged by poor moisture resistance, limited mechanical strength, and source-related ethical concerns. These shortcomings can lead to microbial spoilage, reduced shelf life, and restricted consumer acceptance. Recent strategies to overcome these limitations include the use of cross-linking agents (genipin, citric acid, transglutaminase, etc.) to improve structural stability, incorporation of nanomaterials (silver nanoparticles, zinc oxide, TiO₂, etc.) to enhance barrier and antimicrobial functions, and blending with other biopolymers (chitosan, agar, pectin, cellulose, etc.) for better flexibility and water resistance. Advances in processing techniques such as electrospinning and extrusion molding further optimize film morphology and performance. This review offers new insights by synthesizing these approaches and identifying future research directions focused on scalability, safety assessments, and inclusive sourcing. Gelatin films, when strategically modified, can serve as a viable replacement for conventional plastics in food packaging, offering a pathway toward safer and more sustainable preservation systems.