73D-19 |
Effect of ozone (O3) gas on mechanical, thermal and barrier properties of plastic films used in food packaging |
B. F. OZEN1, J. D. Floros2, and P. E. Nelson1. (1) Dept. of Food Science, Purdue Univ., 1160 Food Science Bldg., West Lafayette, IN 47907-1160, (2) Dept. of Food Science, The Pennsylvania State Univ., 111 Borland Lab., University Park, PA 16802 Due to its oxidizing and disinfectant properties, O3 has recently received attention for the treatment of foods as well as the food processing equipment and packaging materials. Since it is a very strong oxidizing agent, O3 might cause changes in some of the properties of polymeric materials. The objective of this study was to investigate the effect of O3 exposure on the mechanical, thermal and barrier properties of several plastic films used in food packaging. Linear low density polyethylene (LLDPE), oriented polypropylene (OPP) and biaxially oriented nylon (BON) films were exposed to O3 gas (2.1-4.3 mg/L) for 2-24 h in a treatment chamber. After treatment, thermal properties of the films were determined by a MDSC, and an Instron analysis was used in the measurement of tensile strength (TS) and elongation. O2 permeability was measured by an O2 permeability system. Exposure to O3 gas caused changes in the mechanical properties of all the polymers tested. While TS of OPP decreased up to 75% with increasing treatment time, a slight increase of approximately 20% was observed in TS of BON. Melting temperature of OPP and BON decreased with increasing treatment time. Also, up to 50% decrease in O2 permeability of LLDPE and BON films was observed after the treatment. O3 exposure caused significant modifications in the properties of plastic films used in food packaging. Therefore, this study will be helpful for determining the suitability of plastic films for applications involving O3 exposure.
Session 73D, Food Packaging
|