Development of active packaging material based on polycaprolactone/hydroxypropyl methylcellulose nanofibers containing carbon dot nanoparticles for meat preservation

This work demonstrates the feasibility of using a combination of biodegradable polycaprolactone (PCL) and natural-based hydroxypropyl methylcellulose (HPMC) polymers containing carbon dots (CDs) for food packaging applications. CDs were synthesized using the insoluble portion of Zedo gum. The 5% and 15% concentrations of bare Zedo CDs (Z-CD) and nitrogen and sulfur co-doped CDs (TZ-CD) were chosen for incorporation into PCL/HPMC nanofibers (NFs). The PCL/HPMC/Z-CD15% and PCL/HPMC/TZ-CD15% demonstrated improved tensile strength (12.88 and 15.01 MPa), water solubility (30.20 and 42.36%), and water vapor transmittance (0.62 and 0.71 g mm/m2 h kPa)), respectively. When comparing the release of CDs in 10%, 50%, and 95% ethanolic solutions, it was found that TZ-CD released more rapidly than Z-CD from NFs in all three simulants. The CDs-added NFs exhibited potent antioxidant activity (80.5%). More significant antimicrobial activity against S. aureus was observed compared to E. coli. Additionally, reductions in total volatile basic nitrogen and thiobarbituric acid values indicated that beef covered with PCL/HPMC/TZ-CD15% and PCL/HPMC/Z-CD15% NFs had an extended shelf life of more than five days. In conclusion, PCL/HPMC/Z-CD15% and PCL/HPMC/TZ-CD15% NFs can be used as promising biodegradable packaging materials to enhance the shelf life of meat products.