Résumé
The dominance of single-use petroleum-based plastics in food packaging is being challenged by increasing environmental concerns, driving innovation toward biodegradable, bio-based, and non-toxic alternatives. Polylactic acid (PLA) has emerged as a leading candidate due to its renewability and compostability. However, its limited ability to prevent microbial contamination has prompted the integration of antimicrobial agents into PLA-based systems. Traditional antimicrobial packaging relies on agents that diffuse through the polymer matrix, but uncontrolled migration can reduce antimicrobial efficacy and raise food safety issues. To address this, non-migrating systems are being explored. These involve the covalent attachment or immobilization of antimicrobial compounds to ensure sustained activity without migration. Chitosan, a natural biopolymer with inherent antimicrobial properties, has gained attention for its biodegradability, biocompatibility, ease of functionalization and, given its high molar mass, a very low migration rate. This review focuses on recent advances in non-migrating antimicrobial strategies, particularly those based on chitosan incorporated into PLA packaging. Innovative techniques such as surface modification, hybrid nanocomposites, and synergistic bioactive blends showing promise in enhancing the antimicrobial performance of PLA films while maintaining safety and sustainability. These developments offer a pathway toward next-generation food packaging materials that are both environmentally friendly and effective in preserving food quality and safety.