다랑어로부터 추출한 histidine 함유 저분자 peptide의 항산화능을 평가한 결과, histidine, 1-methylhistidine, carnosine과 anserine을 포함한 histidine 관련 화합물과 다랑어에서 추출한 histidine 함유 저분자 peptide는 DPPH 라디칼 소거능력을 지녔고, 농도가 증가함에 따라 효과 또한 증가하였다. 다랑어 추출물은 2차 이온교환 처리물이 carnosine 과 anserine의 dipeptide와 유사한 결과를 나타냈으며, 가열처리와 한외여과를 병행한 경우와 이온교환과 한외여과 처리를 한 동결물의 경우 ascorbic acid와 유사한 라디칼 소거능을 나타냈다. Histidine 함유 dipeptide 중에서 anserine이 가장 높은 환원력을 나타내었으며, carnosine은 두 번째로 강한 환원력을 나타내었다. Dipeptide와 비교하 여 황다랑어, 눈다랑어 추출물이 높은 환원력을 나타내었으며, 농도가 증가할수록 환원력이 증가하였다. 다랑어 추출물 원육에서의 SOD 유사활성은 약했으나, 가열처리와 한외여과를 병행하였을 때, 황다랑어 눈다랑어 추출물이 농도별로 4.0-19.4%, 5.7-20.6%로 나타났으며, 이온교환과 한외여과를 병행하였을 때, 8.3-27.9%, 5.4-25.0%, 2차 이온교환 처리를 하였을 때, 8.2-29.5%, 8.6-32.1%로 활성이 증가하였다. Linoleic acid를 기질로 하여 저장기간에 따른 자동산화의 중간생성물인 과산화물의 변화를 측정한 결과 CM-cellulose의 처리 동결건조물은 ascorbic와 유사하게 지질산화능이 높은 것으로 나타났다. 인체 내의 pH 변화를 고려하여 pH 1.2, pH 3.0, pH 4.2로 조절하여 아질산염의 소거능을 살펴보았을 때, 황다랑어 추출물의 경우 25.14%, 15.09%, 13.71%, 눈다랑어 추출물은 27.44%, 18,28% 18.09%로 pH 1.2, pH 3.0에서 carnosine과 anserine보다 낮지만 pH 4.2에서 histidine 보다 높은 소거능을 보였다.

To extend the shelf-life of chicken breast meat, samples were treated with gel-packs containing slow-released ClO2 gas at 7-15 ppm for 8 days at 4℃. And the changes in lipid oxidation and taste compounds of the samples were investigated. TBARS value of the chicken breast was slightly increased during storage. TBARS value of gas treatments was similar to the control during storage. There were 14 fatty acids in the chicken breast. And there was no change in the fatty acid composition during storage, and there was no significant difference between the control and gas treatments. The content of free amino acids was gradually increased during storage. The content of free amino acids were not significantly different between the control and gas treatments during storage. The content of GMP in the control and gas treatments were decreased during storage. However, gas treatments showed slightly higher content than that of control. AMP was not significantly different between the control and gas treatments. IMP gradually decreased during storage and the content of inosine and hypoxanthine was increased. IMP, inosine and hypoxanthine contents of gas treatment were similar to control, but the control tended to change more rapidly than those of gas treatments.

Even though chlorine dioxide (ClO2) is utilized in a pre-treatment due to its effective sterilizing activity for microorganisms and its safety for food, it has a limitation in maintaining freshness of the food product. In this study, a low-concentration ClO2 gas was produced in a packaging form of air-permeable gel pack so that it could be released continuously over several days. The amount of ClO2 gas emission and microbial inactivation effect against foodborne pathogens were measured during the release of ClO2 gas. As a result of measuring the change of color in order to confirm whether the chlorine dioxide gas was eluted in the form of a sustained release, the yellowness was significantly higher at higher gel pack concentration and higher value during storage periods. The slow-released ClO2 gel-pack showed clear inactivation effect against Escherichia coli and Staphylococcus aureus with 99.9% inactivation efficiency. As a result of measuring the sterilization effect of Listeria monocytogenes by the concentration of chlorine dioxide gas, the sterilization effect was increased as the concentration was increased. Therefore, the slow-released ClO2 gel-pack is feasible to apply for industry usages.

To prolong the shelf-life of chicken breast meat, samples were treated with gel packs containing slow-released chlorine dioxide (ClO2) gas at 7~15 ppm for eight days at 4℃. The microbial, physicochemical properties and sensory evaluation of the treated samples were investigated. The total number of bacteria in the control increased during storage and showed 6.78 log CFU/g on the 8th day of storage, but ClO2 gas treatments showed 6.24~6.58 log CFU/g at the same time. The initial pH of chicken breast meat was 6.00 and gradually increased during storage. And ClO2 gas treatments did not show any significant difference from the control during storage period, but maintained a generally lower pH than that of the control. The lightness, redness, and yellowness during storage were not significantly different between the control and the 7~10 ppm ClO2 gas treatments. However, as the storage period was increased, the redness of 15 ppm ClO2 gas treatment was reduced. The cooking loss and shear force were not different between the control and ClO2 gas treatments during the storage period. Volatile basic nitrogen (VBN) increased in the control from the 6th day of storage and 23.80 mg% in the 8th day of storage. However, VBN of ClO2 treatments showed lower than that of the control. In the change of sensory evaluation during storage, 10 ppm ClO2 treatment showed the highest preference in odor, appearance and overall acceptance during storage period.

To increase the shelf-life of strawberry, samples were treated with two gel packs containing slow-released chlorine dioxide (ClO2) gas at 3~5 ppm for 6 days at room temperature and the changes in the major chemical components (ascorbic acid, polyphenols, flavonoids and anthocyanin) contents and antioxidative activities (DPPH, ABTS radical scavenging and metal chelating activity) were investigated. The content of ascorbic acid of control was 40.38 mg% and contained 35.67~44.75 mg% during 6 days. There was no tendency to increase or decrease during storage period. The contents of ascorbic acid of control and 3~5 ppm ClO2 gas treated samples were not significantly different during storage period. The content of polyphenol compounds of initial stage was 111.23 mg% and contained 117.78~132.40 mg% during 6 days. The contents of polyphenol compounds of 3~5 ppm ClO2 gas treated samples were 103.51~130.25 mg%. There were no significant different between them during storage. The flavonoids and anthocyanin contents were not different from the control during storage period regardless of 3~5 ppm ClO2 gas treatment. Furthermore, antioxidative activities were not different among the control and ClO2 gas treatments during storage.

To prolong the shelf-life of strawberry, samples were treated with gel packs containing slow-released chlorine dioxide(ClO2) gas at 3~7 ppm for 6 days at room temperature. The weight loss and decay ratio as well as changes in pH, color and texture properties of the treated samples were investigated. The weight of the control and ClO2 gas treated samples decreased slightly, but the weight of the control changed faster than those of the ClO2 gas treated samples during the storage period. The decay ratio of control was higher than those of the ClO2 gas treatments since 4 days of storage. The pH and acidity in the control and in the ClO2 gas treated samples were no differences during storage period. The lightness of strawberry decreased during storage, but there was no difference in lightness among the treatments even when storage time was extended. The redness and yellowness of the control showed higher change than those of the ClO2 gas treatments during 6 days. The firmness of the control changed more rapidly than those of the ClO2 gas treatments during 6 days. Especially, the samples treated 3 and 5 ppm ClO2 gas were the least changed. And the scores for appearance, firmness and overall acceptance control and 7 ppm ClO2 gas treatment decreased more rapidly than those of 3 and 5 ppm treatment.

To improve the shelf-life of mushrooms, Lentinula edodes GNA01 mushrooms were treated with gel packs containing slow-released chlorine dioxide (ClO2) gas at 5~10 ppm for 5 days at 20℃ and the weight loss rate as well as the changes in pH, color and texture properties of the treated samples were investigated. The weight of the control and ClO2 gas treated samples were decreased slightly, and there were no differences during the storage period. However, the weight of the control changed faster than those of the ClO2 gas treated samples during storage period. The pH in the control and in the ClO2 gas treated samples were decreased during storage period, but the samples treated with 5 and 7 ppm ClO2 gas were the least changed. On the other hand, the samples treated with 10 ppm ClO2 gas showed no difference from the other treatments during 4 days, but the pH was lower than that of the control on the fifth day. The lightness of inside and outside in mushroom were decreased whereas redness and yellowness were increased during storage period. However, color changes in the ClO2 gas treated samples were lower than those of the control. Especially, the samples treated with 5 and 7 ppm ClO2 gas were the least changed. The texture of the mushroom were decreased consistently during storage period. The texture of the control changed faster than those of the ClO2 gas treatments during 5 days. Especially, the samples treated 5 ppm ClO2 gas were the least changed.