title: Combined Effect of Irradiation and Ageing Condition on Physicochemical and Microbial Quality of Hanwoo Eye of Round.
abstract: The combined effects of electron-beam irradiation and ageing of beef were examined. The irradiated samples at dose of 0 or 2 kGy were kept and analyzed for the microbial growth, shear values, meat color, and nucleotide-related flavor compounds at different ageing temperatures (2, 10, or 25℃) for 8 d. The irradiation effect on inactivation of foodborne pathogens was also investigated. The population of Listeria monocytogenes and E. coli O157:H7 inoculated in beef samples decreased in proportion to the irradiation dose, showing D10 values of 0.66 and 0.65 kGy respectively. The irradiated beef eye of round had lower number of total aerobic bacteria (TAB) than non-irradiated one during the storage, but the TAB increased with higher ageing temperature (p<0.05). Especially, TAB increased sharply in non-irradiated samples aged at 25℃ after 4 d (p<0.05). With increasing ageing temperature and ageing time, shear force values decreased (p<0.05). The color a* values of the irradiated beef were lower than those of the non-irradiated throughout the ageing period (p<0.05). As ageing time and temperature increased, the amounts of inosine monophosphate decreased and the hypoxanthine increased (p<0.05). Relatively high ageing temperature could be used at irradiated beef eye of round to shorten the ageing time.
authors.affiliation: Department of Health Administration and Food Hygiene, Jinju Health College, Jinju 660-757, Korea.
authors.forename: Dong-Gyun
authors.initials: DG
authors.lastname: Yim
authors.affiliation: Department of Agricultural Biotechnology, Center for Food and Bioconvergence, and Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 151-921, Korea.
authors.forename: Cheorun
authors.initials: C
authors.lastname: Jo
authors.affiliation: Department of Agricultural Biotechnology, Center for Food and Bioconvergence, and Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 151-921, Korea.
authors.forename: Hyun-Joo
authors.initials: HJ
authors.lastname: Kim
authors.affiliation: Department of Animal Science and Technology, Sunchon National University, Suncheon 540-950, Korea.
authors.forename: Ju-Su
authors.initials: JS
authors.lastname: Cha
authors.affiliation: Department of Animal Science and Technology, Sunchon National University, Suncheon 540-950, Korea.
authors.forename: Hyun Cheol
authors.initials: HC
authors.lastname: Kim
authors.affiliation: Department of Animal Science and Technology, Sunchon National University, Suncheon 540-950, Korea.
authors.forename: Ki-Chang
authors.initials: KC
authors.lastname: Nam
keywords: ageing temperature; beef; irradiation; meat quality; pathogens