Lemon-derived carbon quantum dots incorporated guar gum/sodium alginate films with enhanced the preservability for blanched asparagus active packaging

Minimally processed fruits and vegetables (MPFVs) experience significant quality degradation during storage due to oxygen exposure, mechanical damage, and microbial contamination, which significantly reduces shelf life and leads to substantial economic waste. This research developed a cost-effective and environmentally active packaging by incorporating carbon quantum dots (CQDs) derived from lemons into guar gum (GG) and sodium alginate (SA) films. The CQDs were integrated into the biopolymer matrix via simple film-casting techniques. The CQDs exhibited exceptional antioxidant and antibacterial properties due to the abundant functional groups and unique quantum effects. The integration of CQDs into GG/SA films enhanced UV-blocking capabilities, mechanical strength (38.80 MPa), and antioxidant activity (43.45%). The release kinetics of CQDs from the films followed the Fickian diffusion kinetics. The use of CQDs offers several advantages over conventional methods including their biocompatibility, sustainability, and multifunctionality. Additionally, the films effectively delayed the browning of blanched asparagus. The mechanism of browning inhibition was attributed to the prevention of chlorophyll degradation and enzymatic browning. This approach offers a sustainable and effective solution for extending the shelf life and safety of MPFVs.