With the emphasis placed by society on environmental resources, current petroleum-based packaging in the food industry can no longer meet people’s needs. However, new active packaging technologies have emerged, such as proteins, polysaccharides, and lipids, in which proteins are widely used for their outstanding gel film-forming properties. Most of the current literature focuses on research applications of single protein-based films. In this paper, we review the novel protein-based packaging technologies that have been used in recent years to categorize different proteins, including plant proteins (soybean protein isolate, zein, gluten protein) and animal proteins (whey protein isolate, casein, collagen, gelatin). The advances that have recently been made in protein-based active packaging technology can be understood by describing protein sources, gel properties, molding principles, and applied research. This paper presents the current problems and prospects of active packaging technology, provides new ideas for the development of new types of packaging and the expansion of gel applications in the future, and promotes the development and innovation of environmentally friendly food packaging.

Food packaging serves a pivotal role in daily life, facilitating the efficient transportation of food and extending its shelf life. Petroleum-derived plastic packaging is extensively employed; however, its non-biodegradable nature poses significant environmental pollution and ecological degradation. Natural polymers (e.g., proteins such as gelatin and corn gluten protein; polysaccharides including pectin, chitosan, starch, cellulose, and alginate) and synthetic polymers (e.g., polyvinyl alcohol, polylactic acid, and polyhydroxyalkanoates) can be utilized to fabricate food packaging films, thereby achieving green and eco-friendly objectives. Nevertheless, the inferior mechanical strength and inadequate antibacterial activity of biopolymer-based packaging have restricted their practical applications. In recent years, nanomaterials (e.g., nanoparticles, nanotubes, nanofibers, and nanosheets) have been employed to enhance the performance of food packaging, emerging as a research hotspot. Notably, nanoparticles possess unique properties, including a high specific surface area, excellent dispersibility, and multifunctionality, which enables them to be easily incorporated into film matrices. Owing to their unique chemical structures, nanoparticles form strong interactions with film matrices, leading to a denser spatial structure. This not only markedly enhances the mechanical strength of the films, but also simultaneously improves their antibacterial and antioxidant capabilities. This review classifies and summarizes common nanomaterials based on their chemical compositions, providing a theoretical foundation and technical reference for the future development and application of nanomaterials in the field of bio-based active food packaging.

Food packaging plays an essential role in maintaining food quality, safety, and shelf life during storage, transportation, and retail distribution. However, conventional petroleum-derived plastics raise increasing environmental concerns, while many biopolymer-based packaging materials remain limited by insufficient mechanical strength, poor water resistance, limited barrier properties, and unstable active functions. Natural extract-based multifunctional gels provide a promising strategy for sustainable food packaging due to their inherent biocompatibility, structural versatility, and synergistic interplay between active extracts and gel networks, which can immobilize bioactive compounds, regulate mass transfer, and integrate preservation and monitoring functions within one material platform. This review summarizes recent advances in natural extract-based multifunctional gels for food packaging, with emphasis on polysaccharide-based, protein-based, lipid-based, and other naturally derived gel systems. Representative material formats include hydrogels, aerogels, emulsion gels, oleogels, and gel-derived films or coatings, while typical components include chitosan, alginate, pectin, starch, proteins, natural waxes, lignin, anthocyanins, curcumin, polyphenols, and essential oils. Their gelation mechanisms, structural features, preparation strategies, and functional applications are discussed, including antioxidant activity, antimicrobial preservation, barrier enhancement, controlled release, freshness monitoring, and biodegradability. Furthermore, the potential interactions between natural extracts and gel matrices are also discussed, including hydrogen bonding, electrostatic interactions, ionic crosslinking, dynamic covalent bonding, hydrophobic association, and lipid crystallization. The main merits of these systems include renewability, biodegradability, tunable network interactions, active-agent protection, and integration of preservation and monitoring functions, whereas persistent challenges include moisture sensitivity, mechanical instability, variable extract composition, migration safety, and scale-up cost. This review provides guidance for designing natural extract-based gel packaging materials with improved functionality, sustainability, and practical applicability.