Cinnamon-loaded PVA/gelatin/starch electrospun fibers as novel sustainable nanocomposites for active food packaging.

This study produced six formulations using polyvinyl alcohol (PVA) blended with gelatin or gelatin-starch, incorporating cinnamon powder (CP) or cinnamon essential oil (CEO). Homogeneous nanofibers with diameters ranging from 367 to 532 nm were obtained. Thermogravimetric analysis showed a three-stage degradation profile with primary mass loss between 290 and 390 °C. DSC analysis revealed two melting transitions (153.6-156.6 °C and 178.2-192.4 °C) and a slight reduction in crystallinity (28.7-36.9%). Formulations containing CEO (NF3 and NF6) showed mechanical improvements compared to neat PVA. NF3 exhibited a high Young's modulus (204.1 MPa), elevated tensile strength (138.2 MPa), and high elongation at break (84.6%), indicating a balance between strength and flexibility. The CEO-loaded nanofibers exhibited antimicrobial activity against Bacillus cereus and Staphylococcus aureus immediately after fabrication and after four months of storage. Moreover, NF3 showed inhibition at 50 mg/mL against S. aureus and B. cereus, and at 100 mg/mL against Listeria monocytogenes and Salmonella Enteritidis. When applied to minimally processed fruits, the nanofibers reduced weight loss, delayed browning, and preserved firmness and color in papayas and apples. In addition, the range of hemolysis values (0.66-4.02%) and the absence of significant cytotoxic effects confirmed their biocompatibility. Only NF6 showed reactivity against L929 cells, but this result may not reflect a lack of safety for human health, as some cytotoxicity is expected from CEO. These results highlight the potential of CEO-loaded nanofibers as active materials to extend the shelf life of minimally processed fruits.