Gamma irradiation at 20 kGy was applied to Kanjang (soy sauce), Doenjang (soybean paste), Kochujang (hot pepper paste) and Chungkukjang for their possible genotoxicity The genotoxicity of 20 kGy-irradiated samples was evaluated by Salmonella typhimurlum reversion assay. The Salmonella tester strains included TA98, TA100, TA1535 and TA1537 in the absence and presence of an exogenous metabolizing system (S9 mix). All samples were negative in the bacterial reversion assay with S. typhimurium TA98, TA100, TA1535 and TA1537. The results indicated that 20 kGy of gamma irradiation on water-soluble fraction of Kanjang, Doenjang, Kochujang and Chungkukjang were not shown mutagenicity.

Microbial populations of total aerobic bacteria -and coliforming bacteria, TBA, Hunter's color value, heme pigments, muscle protein solubility, cooking loss and shear force were investigated for evaluating the shelf life of chicken legs gamma-irradiated at doses of 1, 3, 5 and 10 kGy with air-contained and vacuum-packaged methods. The initial microbial populations decreased with gamma irradiation depending upon the dose, and microorganisms in the vacuum-packaged samples were inhibited more than those in the air-contained samples. TBA values were higher in the air-contained samples than in the vacuum-packaged samples. Hunter's L and a values of the surface and inside of the legs increased by gamma irradiation, showing a bright red color and the red color was maintained during the storage of both samples. The concentrations of oxymyoglobin among the heme pigments increased by gamma irradiation. Muscle protein solubility slightly increased by increasing the applied dose. There were no significant differences in the cooking loss and shear force values. In conclusion, the combination of gamma irradiation and vacuum-packaging could extend the shelf life of chilled chicken without deterioration of the quality.

This study was conducted to evaluate the changes in the quality of rice wine (Makgeolli) treated with UV-C and electron beam (EB) irradiation during its storage at 4℃ for 15 days. The EB irradiation was found to be more effective than the UV-C irradiation for microbiological control. The pH tended to be increased by UV-C, EB irradiation, and storage period. Acidity was significantly higher in rice wine treated with EB irradiation than those of control and UV-C irradiation during storage period. The L*-value of the samples treated with UV-C and EB irradiation tended to be proportionately higher than that of the control, but this was not consistent during storage period. The a*-value of the sample treated with EB was higher than that of the others, but this was not consistent during the storage period. The reducing sugar content was higher in the control at day 0, but it rapidly decreased compared with the control during the storage. The results indicate that EB irradiation was more effective than UV-C irradiation in controlling microorganisms of rice wine. However, a further study is needed to minimize the rice wine quality deterioration caused by UV-C or EB irradiation during storage.

The characteristics of the components related to the meat taste of the commercial broiler (CB) and the Korean native chicken (KNC) were compared. The breast meat from CB showed higher amounts of C16:1 and C18:2 but lower amounts of C16:0 and C22:6. The thigh meat from CB showed a higher amount of C18:1 but lower amounts of C16:0, C18:0, C20:4, and C22:6. The flavor- and taste-contributing amino acids, including aspartic acid, threonine, serine, glycine, alanine, tyrosine, lysine, histidine, and arginine, were significantly higher in the KNC breast meat, but the level of amino acids in the thigh meat were not different between the two breeds. The measurement of the volatile compounds revealed that CB contains much higher volatile compounds compared to KNC in their fresh breast and thigh meat. Both in the breast and thigh meat, however, the amount of flavor compounds increased significantly after cooking; as such, KNC turned out to have more flavor compounds than CB.

유백피의 천연항산화제로서의 이용성을 검토하기 위하여 각종 용매로 유백피 추출물을 제조하여 lard emulsion에 첨가하여 6에서 저장하면서 항산화 활성을 비교하고 항산화 활성이 우수한 추출물을 용매별로 분획하여 항산화 활성, 분획물의 첨가농도의 결정 및 기질특이성을 측정하였다. 또한 생체내에서도 분획물의 항산화 효과를 살펴보기 위하여 흰쥐 간 micmsome 을 사용하여 유도된 지질 과산화 반응에 대한 억제 효과를 측정하였다. 유백피의 추출물