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The objectives of this study are to study the growth of salmonellae in irradiated and non-irradiated beef, and generate computer models of the growth. These models will be used to determine if the reduced natural microflora in irradiated meat affects growth. The primary growth characteristics which are relevant to the growth of these bacteria in foods are the lag phase duration and the generation time.
One of the frequently voiced concerns of consumer groups is that irradiation of meat will create a more favorable environment for the growth of pathogenic bacteria which contaminate the product after irradiation, by eliminating the natural spoilage microflora. The concern is that without the normal levels of spoilage microorganisms which are found in non-irradiated meats, the pathogenic bacteria might be at a competitive advantage to grow at a faster rate or to potentially higher numbers in the irradiated product. A recent hypothesis that has been presented is that our current food supply is too "clean". and that this has in part been responsible for the emergence of some more recent food borne diseases.If correct, this hypothesis would also support the concern that irradiated foods would be more amenable to the growth of food borne pathogens, if the food were contaminated after irradiation.The effect of food irradiation on potential bacterial pathogens in meats has been well documented. Relatively low irradiation doses will effectively eliminate most of the vegetative cells of food borne pathogens at the levels which they are found in meats.