Abstract
Gamma irradiation$(1{\sim}5\;kGy)$ was applied to Korean beef to improve the hygienics and quality preservation. The effective dose of irradiation was 3 kGy for the sterilization of the initially contaminated microorganisms. After 8 weeks of storage at $5^{\circ}C$, no growth of the microorganisms were observed in the samples irradiated above 5 kGy. The pH was slightly increased as storage period increased. However, no significant change in pH was observed by gamma irradiation. The acid value of beef during storage at $5^{\circ}C$ was increased rapidly with the elapse of the storage period in both nonirradiated and irradiated samples, but that of the 3 kGy irradiated samples increased more slowly than the nonirradiated. VBN value increased more rapidly in nonirradiated sample than the irradiated during storage. Especially VBN value of the nonirradiated sample was four fold higher than that of the 3 kGy irradiated sample after 8 weeks of storage at $5^{\circ}C$. No significant differences in the components of fatty acid were observed by gamma irradiation. The amount of released free amino acid was increased during storage and was not significantly affected by gamma irradiation.
한우육의 위생화와 품질보존을 위해 $1{\sim}5\;kGy$의 감마선을 조사하였다. 초기 시료에 오염된 미생물의 살균을 위해서는 3 kGy의 선량이 요구되었다. 5 kGy 이상으로 조사된 시료는 $5^{\circ}C$ 8주후에도 미생물의 생육이 관찰되지 않았다. 저장중 pH변화의 경우 저장기간에 따라 다소 증가하는 경향을 보였으나, 감마선 조사에 의한 영향은 거의 없었다. 지질산가는 냉장저장시 감마선 조사 및 비조사 시료 모두 저장기간에 따라 증가하였으나, 3 kGy 조사시료는 비조사 시료보다 완만한 증가를 나타냈다. VBN함량의 경우 냉장저장시 큰 변화를 나타내었고, 비조사 시료는 저장기간이 경과됨에 따라 크게 증가하였다. 특히 냉장저장 8주후의 비조사 시료는 3 kGy조사 시료에 비해 약 4배의 증가를 나타내었다. 지방산 조성은 감마선조사에 의해 큰 영향이 없었으며, 유리 아미노산 함량은 감마선 조사보다는 저장기간에 의해 많은 변화를 나타냈다.
(Division of Life Science, Hallym University)