Aleksandra Such, Ewelina Węsierska, Magdalena Surma, Anna Winiarz, Aneta Koronowicz
Synthetic plastics remain widely used in food packaging despite environmental concerns. This laboratory-scale study evaluated biodegradable chitosan-alginate films enriched with oregano or turmeric two-phase equilibrium condensates as active packaging films for highbush blueberries (Vaccinium corymbosum L.). Film hydration properties were assessed, and blueberries were stored at 4 °C or 22 °C for 7 or 14 days. Dry matter, proximate composition, total phenolic content (TPC), antioxidant activity, vitamin C, and total viable bacterial count (TVC) were measured. Simulated gastrointestinal film digestates were evaluated in Nthy-ori 3-1 thyroid epithelial and CCD 841 CoN colonic epithelial cells. Oregano-enriched films (OS3) showed greater water uptake and swelling than control and turmeric-enriched films. Blueberry responses depended on formulation and storage conditions. After 14 days at 4 °C, OS2- and OS3-packaged blueberries showed higher vitamin C contents than plastic controls, corresponding to approximately 20% lower vitamin C loss. TVC was primarily influenced by temperature, with no significant main effect of packaging type. Digestates did not significantly alter evaluated DNA-damage markers under short-term exposure conditions. Concentration-dependent cell-cycle changes occurred in Nthy-ori 3-1 cells after OS2 and OS3 exposure, whereas no significant changes were observed in CCD-841CoN cells.