An aerogel-based intelligent active packaging with the dual functions of spoilage detection and freshness preservation

Due to the highly porous (≈96%), lower density (50.71 ± 2.07 mg/cm3) structure of aerogels, which gives them excellent adsorption and release of substances. Furthermore, aerogel-based intelligent, active food packaging may have higher sensitivity than film-based packaging, thus arousing the interest of researchers. In this study, an aerogel was prepared from gelatin, gum Arabic, curcumin, and nisin (GG-cur@Nisin) to achieve the dual functions of spoilage detection and freshness preservation. Scanning electron microscopy observations verified that an interpenetrating polymer network was formed in GG-cur@Nisin. Infrared spectroscopy and X-ray diffraction showed that curcumin and nisin were physically embedded in the aerogel matrix and that van der Waals forces were the main intermolecular interactions. The GG-cur@Nisin aerogels displayed lower density (50.71 ± 2.07 mg/cm3), higher water vapor absorption capacity (0.20 g/g), and lower solubility than films of identical composition. The water contact angle results also showed that the aerogels (90.3° ∼ 92.7°) have more hydrophobic surfaces than the films (51.5° ∼ 61.1°). The GG-cur@Nisin aerogel performed better than the corresponding film in the colorimetric response to 2500 ppm ammonia solution and displayed a sensitive color change to spoilage in shrimp and pork. When used as padding material, the GG-cur@Nisin aerogel can extend the shelf life of pork at 25 °C by up to 6 h. Therefore, the aerogels developed in this study have great potential to ensure food quality and inspire new ideas for intelligent, active packaging. [Display omitted] •Aerogels with both freshness monitoring and preservation functions were prepared.•Aerogels offer enhanced control over the release of curcumin and nisin.•Aerogels have more hydrophobic surfaces than the films.•Aerogels exhibit greater responsiveness to volatile ammonia in comparison to films.