Gelatin-based nanocomposites for food packaging: A comprehensive review of sources, nanofillers, mechanisms, fabrication techniques, properties, and applications

Growing environmental and health concerns associated with petroleum-based food packaging have intensified the demand for sustainable and biodegradable alternatives. Gelatin, a naturally derived biopolymer obtained from animal by-products, has gained considerable attention due to its film-forming ability, biocompatibility and renewability. However, its practical application is limited by inherent drawbacks, including low mechanical strength, high moisture sensitivity and poor barrier properties. To overcome these limitations, the development of gelatin-based nanocomposites through the incorporation of nanofillers has emerged as an effective strategy. This review provides a comprehensive overview of recent advances in gelatin nanocomposites reinforced with various nanofillers, such as inorganic nanoparticles, clay-based, carbon-based materials, biopolymeric and bioactive nanostructures. Emphasis is placed on the role of interfacial interactions and nanoparticle dispersion in governing structure-property relationships and enhancing mechanical, thermal, barrier, optical and bioactive performance. Additionally, fabrication techniques including solution casting, electrospinning, multilayer assembly and extrusion are discussed. The review offers an integrated framework to support the rational design of advanced and sustainable food packaging materials.