The effects of packaging materials, low-dose irradiation, and subsequent storage on inactivation of pathogen were studied. UV-sterilized meat surfaces were inoculated with approximately 5 to 6 log10 CFU/cm2 E. coli O157:H7 or approximately 6 to 7 log10 CFU/cm2 Salmonella Typhimurium, wrapped in plastic sheets of polyethylene, polylactic acid (PLA), polynylon, polypropylene, or low-density polyethylene (LDPE), sealed and vacuum packaged, and subjected to irradiation doses ranging from 0.5 to 2.0 kGy in a60 Co irradiator. Samples were analyzed for remaining bacterial populations immediately after irradiation and after 7 days of refrigerated storage (4°C). For S. Typhimurium, both the effect of packaging material and storage period were significant as compared to untreated samples (p < 0.05). Higher log10 reductions were observed following irradiation at all doses after refrigerated storage period than for day O samples. In general, irradiation resulted in higher log10 reduction of E. coli O157:H7 than S. Typhimurium at the same dose. The following conditions demonstrated maximum log10 reductions in this study: 2.0 kGy irradiation dose, 7-day refrigerated storage at 4°C, LDPE plastic for E. coli O157.H7, and PLA plastic for S. Typhimurium. However, there were no significant differences between the mechanical strength of irradiated and unirradiated plastics (p > 0.05).
|Original language||English (US)|
|Number of pages||9|
|Journal||Transactions of the American Society of Agricultural Engineers|
|State||Published - Jul 1 2004|
All Science Journal Classification (ASJC) codes
- Agricultural and Biological Sciences (miscellaneous)