Evaluation of nanocomposite packaging containing Ag and ZnO on shelf life of fresh orange juice

Abstract

article i nfo 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 (ΔE=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 (pb0.05). Packages containing nanosilver increased shelf life of fresh juice although part of its sensory attributes were lost. Industrial relevance: Compared with pure packaging materials, antimicrobial nanocomposite packages containing Ag and ZnO as an alternative non-thermal technology can extend the shelf life of fresh orange juice up to 28 days. However, a certain concentration of nano-ZnO in the packages showed less adverse effects on sensory characteristics. © 2010 Published by Elsevier Ltd.