Effects of gamma irradiation on microbial load and quality characteristics of veal


1 Department of Food Hygiene, Faculty of Veterinary Medicine, Islamic Azad University of Shahr e kord, Shahr e kord, Iran

2 Department of Medical Radiation Engineering and Radiation Research Center, Shiraz University, Shiraz, Iran

3 Department of Medical Physics and Medical Engineering, Isfahan University of Medical Sciences, Isfahan, Iran

4 Department of Molecular Medicine and Reproductive Endocrinology Research Center, Shahid Beheshty University of Medical Sciences, Tehran, Iran

5 Department of Medical Radiation Engineering, Shahid Beheshty University, Tehran, Iran

6 Private Veterinarian, Isfahan, Iran


Background: Veal is a rich nutrient medium that provides a suitable environment for proliferation of veal spoiling microorganisms and common food-borne pathogens. In this study, the effects of irradiation on the veal microbiological quality and half life of minced beef during chilled storage was investigated. Materials and Methods: Twenty samples of minced veal were irradiated with doses of 2, 5, 7, and 10 kGy (Cobalt-60, gamma cell 220) and evaluated for their microbiological quality up to 10 days. Results: The results showed that gamma irradiation reduced the number of microorganisms in all the irradiated minced veal samples, with 2, 5, 7, and 10 kGy (P < 0.01). Moreover, the half life of the samples were increased considerably (P < 0.01). In addition, the results indicated that there was a significant difference in the number of coliformes between untreated and irradiated samples (P < 0.05). While, Staphylococcus aureus could not be detected in the irradiated samples with doses of 7 and 10 kGy. Conclusion: These results indicated that irradiation could be employed as an effective mean to inactivate common food-borne pathogens namely S. aureus and increases the half life of veal.


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