Preparation and characterization of Ag@MOF-eugenol/ poly (lactic acid) composite films for zucchini preservation

The rising demand for premium quality fruits and vegetables has resulted in an increased necessity for the advancement in active food packaging. This study aimed to develop eugenol-loaded Ag@MOF/poly(lactic acid) (Ag@MOF-EU/PLA) composite films to assess their efficacy in preserving zucchini. The results revealed that Ag@MOF-EU can be uniformly distributed within the PLA matrix, which significantly enhanced the tensile strength, hydrophobicity, and UV-blocking capacity of PLA films, and at the same time had no significant effect on the thermal properties and WVP of the PLA films. Moreover, the resulting Ag@MOF-EU/PLA films exhibited no cytotoxicity. In a food simulant (50 % ethanol), the release behavior of the EU demonstrated a sustained release over 20 days. Furthermore, Ag@MOF-EU/PLA had an enhanced antimicrobial activity and DPPH scavenging activity, compared to PLA films. The preservation experiment involving zucchini elucidated that the Ag@MOF-EU/PLA composite film could extend the shelf life of zucchini by maintaining color, reducing weight loss, delaying the decline in firmness, and inhibiting the growth of total viable colonies. These findings indicated that the Ag@MOF-EU/PLA films developed within the scope of this research possess the potential to serve as effective food-active packaging materials.