Design of new natural antioxidant active packaging: Screening flowsheet from pure essential oils and vegetable oils to ex vivo testing in meat samples

Two essential oils and seven vegetable oils were tested in an in situ generator of hydroxyl radicals for determining their antioxidant capacity. Then twenty-two different active LDPE films were prepared by incorporating both the essential oils and vegetable oils. The antioxidant capacity, heat-sealing properties and aroma of developed films were determined. The films with the best antioxidant properties, containing flaxseed oil, ginger essential oil, grape seed essential oil and rose oil, were selected and applied as active packaging for fresh meat and tested at industrial scale. The optimum packaging corresponded to 50 μm LDPE film with flaxseed oil which was able to extend by 22% the shelf-life of fresh meat. It was proven that the concentration of flaxseed oil was crucial for antioxidant capabilities of film. Finally, derivatisation was applied to evaluate stability of flaxseed oil packaging. Stability assays suggest that active films should be kept in closed aluminium bags to prevent flaxseed oil oxidation by air and light.