Gamma Irradiation of Ready-to-Cook Bulgogi Improves Safety and Extends Shelf-Life without Compromising Organoleptic Qualities

  • Jo, Cheo-Run (Team for Radiation Food Science and Biotechnology, Korea Atomic Energy Research Institute) ;
  • Han, Chang-Duk (Team for Radiation Food Science and Biotechnology, Korea Atomic Energy Research Institute) ;
  • Chung, Kang-Hyun (Haema Foods Co., Ltd.) ;
  • Byun, Myung-Woo (Department of Food Science and Technology, Seoul National University of Technology)
  • Published : 2003.06.01


We investigated the effects of gamma irradiation on the microbiological, chemical and sensory qualities of bulgogi, a traditional Korean meat product. Gamma irradiation reduced the number of coliform bacteria and bacterial colonies counted in Salmonella-Shigella selective agar to a non-detectable level. Thermophillic microorganisms (mainly Bacillus spp.) in bolgogi refrigerated for 20 days were also significantly reduced by 3 log cycles by 2.5 to 7.5 kGy of irradiation, compared to the control. Electron donating ability and shear force of ready-to-cook bulgogi was not significantly affected by gamma irradiation. Irradiation increased the 2-thiobarbituric acid reactive substances (TBARS) value. The irradiated, raw, ready-to-cook bulgogi had significantly higher scores in color and appearance than those of non-irradiated controls from sensory evaluation. The overall acceptance of cooked bulgogi had higher scores in non-irradiated or 2.5 kGy-irradiated bulgogi than the 5.0- or 7.5-kGy irradiated counterparts. In conclusion, irradiation at 2.5 kGy is recommended as a method to improve shelf-life, safety, and to achieve acceptable quality of ready-to-cook bulgogi without any adverse changes in the sensory characteristics.


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