From natural polymer hydrogels to food packaging films: recent advances in preparation, properties, and applications

Recent advances in food packaging research focus on developing sustainable and biodegradable alternatives to conventional synthetic plastics. Natural polymer hydrogels possess a distinctive combination of characteristics-including high water absorption capacity, controllable swelling properties, biocompatibility, and stimuli-responsive behavior, which collectively position these materials as promising candidates for innovative food packaging. This study aims to provide a comprehensive overview of recent advances in natural polymer hydrogels for food packaging applications. The raw materials of various natural polymer hydrogels are discussed, with a focus on their three-dimensional network construction and film-forming techniques. Furthermore, the functional properties, current applications, challenges, and potential strategies for future development of natural polymer hydrogel food packaging are thoroughly reviewed. Natural polymer hydrogel films exhibit exceptional performance, significantly fulfilling the core demands of modern food packaging systems. By employing strategies such as reinforcing crosslinking structures and incorporating active ingredients, both the physicochemical properties and multifunctional adaptability of these hydrogel packaging materials can be enhanced, enabling their application in diverse food preservation scenarios. Furthermore, intelligent hydrogel packaging systems with tailored functionalities have been developed to enable real-time monitoring of food freshness, detection of hazardous substances, and precision-controlled release of active compounds.