EFFECT OF NANOCOMPOSITE PACKAGING CONTAINING AG AND ZNO ON REDUCING PASTEURIZATION TEMPERATURE OF ORANGE JUICE

Abstract

Nanocomposite low-density polyethylene (LDPE) films containing Ag and ZnO nanoparticles were prepared by melt mixing process through the twin-screw extruder. Packages prepared from nanocomposite films were then filled with fresh orange juice, pasteurized (at 55 and 65C for 16 s) and then stored at 4C. Microbial stability, ascorbic acid (AA) content, browning index and color value of the juice were evaluated after 7, 28, 56, 84 and 112 days of being stored. The two-way interaction between heat treatment and packaging type on the characteristics of the orange juice was investigated. Consequently, application of LDPE nanocomposite packaging containing Ag markedly decreased the pasteurization temperature (65C) of orange juice by 10C. Moreover, the reduced degradation of AA was observed in orange juice, which was filled in nanocomposite packaging containing nano-ZnO. PRACTICAL APPLICATIONS Development of the novel technologies that offer reduced energy consumption and increased quality of fruit juice are of the interest in the food industry. Compared with pure packaging, antimicrobial nanocomposite packages containing Ag and ZnO as an alternative nonthermal-processing technology can reduce the temperature of orange juice light pasteurization while produce juice with higher quality.