Application of sodium alginate-pectin active intelligent film containing anthocyanins from Aronia melanocarpa and tea polyphenols in pork preservation and freshness monitoring

To investigate the preservation effects of active intelligent packaging film (S/P/A/T film) incorporated with anthocyanins (AMA) and tea polyphenols (TP) on meat, pork was selected as a representative sample, and preservation and monitoring experiments were conducted at 4 °C. The antimicrobial properties of the S/P/A/T active intelligent packaging were confirmed by observing the effects of the film solution on the growth curves and bacterial morphology of S. aureus and E. coli. The possible antibacterial mechanism was revealed by molecular docking technology. Finally, the prepared active intelligent packaging was applied to the preservation and freshness monitoring of chilled pork. The study investigated the changes in physicochemical indicators, sensory quality, microbial communities, metabolite characteristics, and the color response capability of the active intelligent packaging during the storage of packaged chilled pork. The S/P/A/T film packaging could inhibit the increase in pH, total volatile basic nitrogen (TVB-N), total viable count (TVC), b* value, and adhesiveness of chilled pork, while delaying the decline in hardness, springiness, a* value, L* value, and sensory quality. The film could extend the shelf life of pork by 3 d. The film also reduced the abundance of spoilage bacteria in the pork and delayed the production of off-flavor substances during pork spoilage. The active intelligent film exhibited a favorable color response during the freshness monitoring of pork. The aforementioned results indicate that the prepared active intelligent packaging has excellent preservative and antimicrobial effects on chilled pork and can monitor the freshness of pork in real-time. Therefore, the development of active intelligent packaging based on S/P/A/T provides promising prospects for meat preservation and freshness monitoring.