Carbon dots as sustainable antioxidants in active food packaging applications: A review

Background: Oxidative deterioration significantly limits the shelf life and quality of food products, while consumer demand grows for safer, more sustainable packaging. Carbon dots, owing to their tunable surface chemistry, structural versatility, and potent antioxidant capacity, are emerging as promising alternatives to conventional chemical antioxidants in active food packaging. Scope and approach: This review examines the antioxidant mechanisms of carbon dots, including hydrogen atom transfer, single-electron transfer, single-electron transfer–proton transfer, radical adduct formation, and the interruption of oxidative chain propagation, across diverse food systems. This study evaluates the effect of carbon nanodots on preserving the sensory characteristics and nutritional quality of fresh produce, meat, seafood, dairy products, beverages, and bakery products by preventing lipid and protein oxidation. The review also examines the sustainability, cost-effectiveness, scalability, and safety of carbon dots, particularly those sourced from edible or agro-biomass materials, and discusses the commercialization potential in clean-label and convenient food packaging sectors. Key findings and conclusions: Carbon dot-based packaging effectively suppresses multiple oxidation pathways, thereby safeguarding the sensory and nutritional attributes of food across various categories. Edible or biomass-derived carbon dots demonstrate low toxicity, biocompatibility, and potential for safe human exposure. Coupled with their sustainability and economic viability, carbon dots present a commercially appealing alternative to conventional antioxidants, poised to advance clean-label, sustainable packaging in oxidative-sensitive products, particularly within the convenience food industry.