Incorporation of natural polyphenols, obtained from blueberry by-products, as active agent for raspberry packaging applications

The study explores the extraction of polyphenols from blueberry by-products, using a green extraction method, and their incorporation into poly-butylene adipate terephthalate (PBAT) electrospun pads for potential use in active packaging. Different solvents were evaluated for their efficiency in extracting polyphenols. The extract obtained using ethanol as a solvent was used for pad production (TPC 370 mg/L). After solubilizing the active extract in the polymer, electrospinning technique was used for obtained the active mat. The resulting active pads were characterized to confirming the preservation of PBAT's structural integrity and thermal stability. Kinetic release tests demonstrated a rapid release of polyphenols compounds into a food simulant (acetic acid 3 % v/v), with nearly complete release observed within 5 h (maximum release 98 %). Raspberries shelf-life test has been applied to test the pads performances. A control packaging and an active packaging were compared over an 11day storage period that simulated a realistic fruit supply chain: four days of cold refrigeration at 4 degrees C followed by storage at 15 degrees C until day 11, simulating supermarket refrigerated display cases. The active pads significantly reduced the fruits incidence of disease and maintained total polyphenol content throughout storage, without negatively impacting weight loss parameters. Overall, the study highlights the potential of utilizing natural polyphenols from food waste in creating sustainable, bioactive packaging solutions that enhance the shelf life and quality of perishable fruits.