Development of novel intelligent and edible dual-functional electrospun nanofiber films for shrimp preservation and freshness monitoring in real-time

The developed trend of novel intelligent packaging materials is changing from food traditional appearance detection to actual spoilage monitoring, aiming to supply a strategy to determine the edibility of food. In this work, a dual-functional electrospun nanofiber film (NFM) noted GZAT was prepared by the co-loading of anthocyanin (ANT) and thymol (THY) into polymer fibers of gelatin and zein. The prepared film was extensively characterized. The GZAT film displayed enhanced mechanical properties and decreased water vapor permeability (WVP) compared with gelatin/zein film (the control). The GZAT film also displayed excellent sensitive colorimetric responses to the pH solutions. Moreover, it exhibited excellent antioxidant property and antibacterial behavior against Escherichia coli ATC25922 ( E. coli ), Listeria monocytogenes ATCC 19115 ( L. monocytogenes ) and Staphylococcus aureus ATCC 6538 ( S. aureus ). Not only that, the dual functions of the GZAT film were confirmed that the shelf life of packaged shrimps was successfully extended to 11 days at 4 °C along with the colorimetric response indicating the freshness of the shrimps. Based on the above characteristic, the prepared GZAT film exhibited great potential as an intelligent packaging film with both real-time freshness indicator and freshness preservation.