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چکیده
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Nanocomposite LDPE films containing Ag and ZnO nanoparticles were prepared by melt mixing in a twin-screw extruder. Packages prepared from the films were then filled with fresh orange juice and stored at 4 °C. Microbial stability, ascorbic acid (AA) content, browning index, color value, and sensory attributes of them were evaluated after 7, 28, and 56 days of storage. Packages containing the nanomaterials, expect 1% nano-ZnO, kept the microbial load of fresh juice below the limit of microbial shelf life (6 log cfu/ml) up to 28 days The least degradation of AA (80.50 mg/100 g), development of brown pigments (OD = 0.23) and losing of color (∆E = 6.0) were observed in pouches containing 0.25% nano-ZnO, after the same time. Sensory attributes were also ranked highest for the juice thus packed in the recent packages after 28 days (p < 0.05). Packages containing nanosilver increased shelf life of fresh juice although part of its sensory attributes were lost.
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