Electrospinning zein with theaflavin: Production, characterization, and application in active packaging for...

The interest and demand for active food packaging made from all natural materials have increased significantly, driven by the intent to minimize the ecological impact. Green electrospinning from biopolymers with antimicrobial compounds is considered an ideal candidate for constructing ultrathin, excellent performance, and effective antibacterial fibrous films (FFs). Here, a green electrospinning from zein (Z) ethanol-aqueous solution with varied theaflavin (TF) concentrations (0.6-4 %) was utilized as active packaging for cold-fresh pork. All the Z/TF composite fibrous films (ZTF-FFs) exhibited smooth and uniform surfaces, and their average fiber diameter increased from 484 nm to 705 nm with higher TF concentration. TF addition altered the secondary and crystalline structure of Z-FF, evidenced by Fourier-transform infrared spectroscopy and X-ray diffraction. At 1 % TF addition, ZTF1-FF displayed enhanced thermodynamic stability, with a decomposition residue of 13.88 % and a maximum mass loss rate temperature of 313.45 °C. ZTF1-FF also exhibited excellent hydrophobicity, superior mechanical properties, and significant antibacterial activity against S. aureus and S. paratyphi B. When used for active packaging of cold-fresh pork, ZTF1-FF significantly delayed the increases in total volatile basic nitrogen, total viable count, pH, weight loss, and thiobarbituric acid reactive substances of the pork. Overall, ZTF1-FF showed the most promising potential as an active food packaging material, particularly for preserving cold-fresh meat.