Development of multifunctional starch/pectin composite film engineered with ZIF-67-loaded microcrystalline cellulose for real-time monitoring and preserving of pork freshness.

The escalating environmental concerns associated with plastic waste have driven the need for sustainable food packaging solutions. In this study, a multifunctional composite film was developed to simultaneously monitor and preserve pork freshness. The film was based on loquat seed starch (LSS) as the matrix, pectin (P) and cobalt-based metal-organic framework (ZIF-67)-loaded microcrystalline cellulose (ZIF-67@MCC) as strengthening and colorimetric fillers. The synergistic effects of P and ZIF-67@MCC significantly modified the microstructure of the LSS-based film, making it compact through extensive hydrogen bonding, resulting in improved UV blocking, mechanical strength, and water/gas barrier. The LSS-based films also exhibited superior antibacterial activity, ammonia-induced color sensitivity, and favorable biosafety and biodegradability. The color of LSS/P/ZIF-67@MCC-5 % film shifted from lavender (fresh) to dark brown (spoiled) over time during pork storage, enabling real-time monitoring of pork freshness. Furthermore, this film effectively preserved the shelf-life of pork to 8 days at 4 °C. This work opens a novel avenue to develop sustainable and intelligent/active composite films for food packaging applications.