Protein–Polysaccharide Hydrogels for Active and Intelligent Food Packaging: A Review

ABSTRACT Protein–polysaccharide hydrogels are increasingly being considered as sustainable, active and intelligent food packaging materials because they are biodegradable, biocompatible with the biological system and capable of forming adaptive three‐dimensional matrices. Unlike previous in‐depth reviews of hydrogels, this article emphasises synergistic interactions between proteins and polysaccharides and their role in designing multifunctional food packaging materials. The article discusses the structure–property relationships of promising protein–polysaccharide pairs such as whey–alginate, gelatin–chitosan and soy–pectin, and discusses how hydrogen bonding, electrostatic interactions and covalent cross‐linking control gel strength, swelling, barrier properties and responsiveness to stimuli. Advanced processes such as pH‐ and CO 2 ‐induced barrier modulation, management of bioactive release and real‐time monitoring of spoilage by integrated biosensing are discussed at the forefront. The paper critically assesses emerging applications such as 3D‐printable hydrogels, antimicrobial absorbent pads and nanocomposite films for fresh foods, considering their scalability and regulatory challenges. Key findings indicate that the incorporation of nanomaterials or bioactive components into hydrogel matrices enhances mechanical stability, moisture and gas barrier functionality, improves antimicrobial and antioxidant activity, thereby enhancing food quality and shelf life with decreased environmental burden. By combining molecular design principles and technological advances, this review presents a focused strategy for the development of biodegradable, intelligent and multifunctional hydrogel‐based food packaging materials whilst filling existing knowledge gaps and enabling transformation to sustainable food preservation technologies.