effect of rosemay extract coated polymeric film (ldpe) for inhibition of butter oxidation

antioxidant active packaging is one of the active packaging that prevents of lipid oxidation by releasing antioxidant during storage of food. in recent years the use of natural antioxidant instead of the synthetic variety in these packaging has been considered. the aim of this study was evaluating the performance of polymeric film coated with natural antioxidant (rosemary extract) to prevent lipid oxidation in butter. with three different concentrations (0.1%, 0.15%, 0.2%), the ethanolic extract of rosemary was sprayed on the surface of low density polyethylene films (ldpe). films without extract was used as control. phenolic compounds migration from the surface of film to 95% ethanol (fatty food stimulant) was measured at 4ºc during 10 hours. with increasing time and extract concentration, migration to ethanol increased (p<0.05). oxidative stability of pasteurized butter components packaged with polyethylene film containing extract and without extract was evaluated in freezing (-18°c) and refrigeration (4°c) temperatures during 4 months and 45 days respectively. the index value of peroxide, free fatty acids (ffa) and sensory characteristics of the samples were investigated during storage. in both temperature, coating of extract on the surface of polyethylene film resulted in reduction of peroxide value and free fatty acids in butter samples (p<0.05). in both temperatures, increasing the extract concentration caused flavor changing of butter and consequently decreasing in public acceptability (p<0.05). film coated with an extract concentration of 0.1% produced most desirable oxidative stability and sensory characteristics at both temperatures.