Antimicrobial Fiber Film Sprayed with Low-Dose Ethyl Lauroyl Arginate for Postharvest Preservation of Strawberries

Antimicrobial packaging is critical for extending shelf life and enhancing safety. Current materials often require large amounts of antimicrobial agents to achieve sufficient efficacy, leading to safety risks and cost issues. In this study, low-dose, safe, and antimicrobial-enhanced polyethylene terephthalate-ethyl lauroyl arginate (PET-LAE) composite fiber films were fabricated by spraying LAE onto electrospun PET fiber films. Systematic investigations evaluated the effects of LAE incorporation on the morphological characteristics, wettability, mechanical properties, water vapor permeability (WVP), and antimicrobial activity of fiber films, with LAE release behavior assessed in food simulants. Results showed that LAE addition improved the hydrophilicity, mechanical properties, and WVP of the fiber films while preserving their original thermal stability. Release experiments under simulated food conditions demonstrated that effective release (with a specific amount of 132.69-144.61 mg/kg, below FDA's 200 mg/kg safety limit) could be achieved by adding only 0.3 wt% LAE to the PET matrix. Notably, this minimal dosage of LAE exhibited high-efficiency antimicrobial activity; Escherichia coli and Staphylococcus aureus counts reduced by (2.13 ± 0.08) and (5.46 ± 0.01) log₁₀ CFU/mL, respectively, while Botrytis cinerea and Colletotrichum gloeosporioides counts decreased by (1.33 ± 0.04) and (0.30 ± 0.01) log₁₀ CFU/mL, respectively. Furthermore, the PET-0.3% LAE fiber film effectively maintained strawberries freshness. At room temperature, the control group's shelf life was 3 days, while that of the PET-0.3% LAE group extended to 7 days, representing a 4-day extension compared with the Control group. This work provides a useful solution and a new viewpoint on active packaging, creating new opportunities to develop antimicrobial materials with improved performance and reduced agent usage. To prevent strawberry decay and effectively extend their shelf life, a low-dose, safe, and antimicrobial-enhanced composite fiber film was successfully prepared. Spraying a low dose of LAE onto the surface of electrospun PET fiber films not only enhanced the fiber's resistance to microorganisms but also effectively maintained strawberry freshness, extending the shelf life of strawberries by 4 days at room temperature. This study provides an important reference for the development of antimicrobial functionalized preservation packaging materials and opens up a new path for active packaging technologies.