From concept to reality: current trends in developing tunable biopolymeric materials for food contact applications

This review provides an in-depth synthesis of current strategies to tune the functional properties of microbial- and plant-based biopolymers for food contact applications. Focusing on materials such as polyhydroxyalkanoates (PHAs), bacterial cellulose, starch derivatives, carboxymethyl cellulose, and soy protein isolates, we analyze how polymer performance can be enhanced through chemical modifications and the incorporation of active additives like nano-silica, cellulose nanocrystals, clove essential oil, and silver nanoparticles. Processing innovations, including 3D printing and electrospinning, are critically assessed for their role in improving mechanical strength, barrier performance, and antimicrobial activity, achieving up to a 40% reduction in microbial spoilage rates in certain food products. Particular attention is given to balancing material tunability with regulatory compliance, highlighting concerns related to additive migration and the strict safety assessments required under EU Framework Regulation EC 1935/2004 and upcoming Packaging and Packaging Waste Regulation (PPWR). Scalability challenges including the high production costs of microbial polymers and the limited industrial use of nanomaterials due to safety and economic constraints are evaluated alongside emerging solutions such as waste-derived feedstocks and metabolic engineering. By consolidating evidence from over 200 studies, this review establishes a detailed framework for the design of cost-effective, scalable, and regulatory-compliant biopolymeric materials, bridging laboratory innovation and industrial application for sustainable food packaging.