Vaccinium corymbosum-Derived Carbon Dots and Anthocyanin-Infused Gelatin Multifunctional Films for Smart Packaging Applications

Consumers and food industry stakeholders have expressed great interest in using simple, non-destructive and inexpensive methods to control/maintain or monitor the freshness of perishable foods. The idea of smart packaging has been introduced to address these requirements satisfactorily, revolutionizing conventional food packaging. Vaccinium corymbosum (VC)-based carbon dots (CDs) and anthocyanin were matrixed on gelatin (GEL) to fabricate smart packaging film. The VC biowaste-derived carbon dots (VC-CDs) were characterized using photoluminescence, fluorescence spectrometry, FTIR, antibacterial/antioxidant potential, TEM and XPS analysis. Fabricated films were subjected to physico-chemical, antioxidant and optical properties, SEM, TGA simulation and in vivo food model system. The VC-CDs exhibited excellent functional properties like ultraviolet (UV) blocking and antibacterial properties. The reinforcement with 1.5% VC-CDs and 6% VC anthocyanins (VCA) in the GEL polymer matrix improved UV blocking (> 189%) properties and showed potent antioxidant potential (> 164%) compared to the neat GEL film. In vivo food packaging (minced pork, fish and shrimp) with films has shown that indicator films work efficiently and non-destructively and monitor real-time freshness. The GEL/VC-CDs/VCA-based active and intelligent films are expected to be applied as multifunctional nanocomposite packaging materials that can indicate quality changes in real time, maintain quality and prolong the shelf life of packaged foods.