Radio-sensitivity of pathogens in inoculated prepared foods of animal origin

Abstract

The effectiveness of irradiation for inactivating Staphylococcus aureus, Listeria ivanovii, Salmonella Typhimurium, and Escherichia coli in the prepared foods of animal origin was investigated. Commercially available seasoned and cooked beef, fried egg, and ham were purchased, radiation-sterilized, and inoculated at 10(6)-10(7) CFU/g with each of the four pathogens and stored at three storage conditions at 10degreesC, 20degreesC, and 30degreesC. D-10-values of S. aureus, L. ivanovii, Salmonella Typhimurium, and E coli were 0.34+/-0.01, 0.24+/-0.02, 0.24+/-0.01, and 0.27+/-0.01 kGy, respectively. No viable cells were detected at 3 kGy of irradiation. Salmonella mutagenicity assay (Ames test) indicated that the 10 kGy irradiated samples were statistically similar to non-irradiated control samples in the Salmonella mutagenicity assay (Ames test). These studies demonstrate that irradiation can be used as an additional safety tool to produce micro biologically safe and wholesome prepared foods of animal origin. (C) 2004 Elsevier Ltd. All rights reserved.