Development of antioxidant active films containing tocopherols to extend the shelf life of fish

With the purpose of develop active films for fish, five natural products with antioxidant properties containing tocopherols were selected and their antioxidant activity in vitro was tested using the DPPH method. In addition these antioxidants were also tested directly on the salmon muscle using the TBARS method. Besides, thermal degradation and differential scanning calorimetry tests allow us to select the products for incorporation into the polymer matrix. Then, two natural products have been selected and incorporated in low density polyethylene films. Film 2 and Film 3, which contain product C at 1 and 5% respectively, presented a reduction in lipid oxidation up to 30% for Film 2 and to 40% for Film 3. Film 4, which contains 5% of product D, reduced lipid oxidation during storage around 30-35 %. The results showed that Film 3 was the most effective to salmon conservation at long-term storage. These films could be used as future active packaging by the food industry for the salmon conservation to extend its shelf life. (C) 2012 Elsevier Ltd. All rights reserved.