الفهرس 
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Abstract
Ionizing radiation, such as gamma radiation, electron beams, and X-ray, is currently approved and used as a non-thermal process for assuring the safety and quality of food. The study objectives include examining of impact for three irradiation sources on the viability of some the food- borne pathogens namely E. coli, S. aureus, P. mirabilis, L. monocytogenes, and E. faecalis in meat products, as well as the microbiological quality of some meat products; and the impact of gamma and electron beam irradiation on selected pathogens inoculated in smoked turkey slices. According to the D10 -value, results showed that X-rays were the most effective form of radiation against tested pathogenic bacteria, followed by gamma radiation. The highest sensitivity of examined bacteria that responded to irradiation was E. coli and the most resistant bacteria was E. faecalis. Inject on of smoked turkey samples with a mixture of the above-mentioned bacteria in the presence of natural microflora, followed by exposing them to 2.0, 4.0, and 6.0 kGy of radiation, allowed assessing how radiation affects the bacterial growth. At a dose of 4.0 kGy (gamma or electron beam radiation), these bacteria were inhibited to undetectable levels (<1 log), and the total bacterial counts were significantly decreased, this may indicate that the used irradiation dose could be used to control some foodborne pathogenic bacteria of public health concern. To improve quality and extend the shelf life of smoked turkey slices, both gamma and electron beam irradiation were utilized. The outcome of this experiment demonstrated that gamma
irradiation was more efficient than electron beam irradiation in reducing
TBC, but both sources had the same impact on total mold and yeast, coliform, and all chosen pathogenic bacteria. The sensory qualities of the smoked turkey were not significantly different with non-irradiated sample while TBA slightly increased with irradiation. Twelve A. flavus isolates were also isolated from black pepper and onion powder in this study, the effect of three radiation sources were examined on only two species of A. flavus isolates that produced the highest aflatoxin amount. It was concluded that X-ray irradiation is more effective than gamma and electron beam irradiation (through their D10 -value). Gamma and electron beam irradiation as well were used to disinfect dried onions and black pepper. Also obtained results confirm that, in a dose-dependent manner, irradiation with either gamma or with electron beam considerably reduced the microbial load of black pepper and dried onions. Even after three months of storage, as indicated, the microbial load of all irradiated black peppers and dried onions were in the permissible range.