Sustained-release electrospun films incorporated with oregano essential oil: Characterization, release kinetics and active packaging application for chicken breast

Sustained-release nanofilms incorporated with oregano essential oil (OEO) were developed by emulsion electrospinning using polyvinyl alcohol (PVA) and quaternary-ammonium chitosan (QAC). The SEM, FTIR and XRD results showed that OEO was successfully encapsulated in the PVA/QAC nanofiber with a diameter range of 158.0–179.6 nm. The incorporation of OEO significantly enhanced the mechanical and barrier properties of PVA/QAC nanofilm, concomitantly mitigating its hydrophilic nature. The prepared PVA/QAC-OEO nanofilms demonstrated excellent antioxidant properties and antimicrobial activities against S. aureus and E. coli (the maximum inhibition zones achieving 23.13 ± 0.72 mm). The release kinetics results showed sustained release of OEO from the PVA/QAC nanofilms, and the release kinetics of OEO adhered to the Fickian + First order dynamics model (R² = 0.9570–0.9997), indicating that a combination of random diffusion and polymer structural relaxation influenced the release of OEO. Furthermore, preservation research showed that the PVA/QAC-OEO nanofilms significantly inhibited the rise in pH, total volatile base nitrogen (TVB-N), thiobarbituric acid reactive substances (TBARs), and total viable count (TVC) in chicken breasts stored at 4 °C, while also maintaining their color and texture properties. Particularly, chicken breasts wrapped in PVA/QAC-OEO₃ film exhibited an extended shelf life for 4 days. Therefore, the PVA/QAC-OEO nanofilms could be a prospective packaging material for meat preservation.