• 한국식품과학회지
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• 제31권1호
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• pp.252-256
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• 1999

한우육의 사태(M. Semitendinosus)를 대상으로 감마선 조사선량(0, 1, 3, 5, 10 kGy)에 따른 지질성분과 항산화 효소 활성도 및 ${\alpha}-tocopherol$ 함량의 변화를 측정하였다. 총 콜레스테롤, LDL-콜레스테롤, HDL-콜레스테롤 및 중성지질 함량에서는 비조사군과 조사군간에 유의적인 차이를 보이지 않았다(p>0.05). 항산화 효소의 활성에서 GST, catalase, SOD 역시 비조사군과 조사군간에 유의적인 차이를 보이지 않았다(p>0.05). 한편, 등심부위의 ${\alpha}-tocopherol$ 함량은 감마선 조사선량이 증가함에 따라 유의적으로 감소되었다(P<0.05).

• 한국식품조리과학회지
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• 제24권1호
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• pp.114-120
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• 2008

In this study, the effects of gamma irradiation on the microbial, physical characteristics, sensory qualities and antioxidant activity of Kongnamul Muchim(cooked soybean sprouts) were investigated. Gamma irradiation at 3 kGy inhibited microbial growth until 4 weeks of storange at $4^{\circ}C$ and until 5 days at and $25^{\circ}C$. The 3 kGy dose did not significantly affect the hardness of the sprouts; however Hunter's color values for lightness, redness and yellowness were changed. Low-dose gamma irradiation(up to 2 kGy) did not significantly affect the antioxidant activity of the Kongnamul Muchim. Also, based on a triangle sensory test, the gamma irradiated Kongnamul Muchim was not significantly different from the control. From these results, it is suggested that the applying gamma irradiation to cooked vegetables at doses lower than 3 kGy is recommended to extend shelf-life and maintain quality characteristics.

• Preventive Nutrition and Food Science
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• 제7권3호
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• pp.273-277
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• 2002

Physiological properties of root and stolen of Gamcho (Licorice, Glycyrrhiza uralensis Fischer) were compared following irradiation at 20 kGy. The root and stolen of Gamcho were extracted with 70 % ethanol, irradiated and stoved in a 4"C refrigerator. Irradiation induced color changes, electron donating ability (EDA), and tyro-sinase inhibition effect (TIE) were investigated. The color of the non-irradiated stolen extract was darker than the non-irradiated root extract (p<0.05), but irradiation eliminated color differences between stolen and root extracts. Generally, irradiation did not affect EDA and TIE of either of the extracts. However, EDA and TIE were higher in stolen extract than in root extract, when the higher dilution factor was considered. These results indicate that the stolen of Gamcho, which is mostly wasted, is a valuable source of phytochemicals with greater EDA and TIE activities than Gamcho root.root.

• Food Science and Biotechnology
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• 제14권1호
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• pp.1-5
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• 2005

Photostimulated luminescence (PSL), thermoluminescence (TL), electron spin resonance (ESR), and direct epiflourescent filter technique/aerobic plate count (DEFT/APC) were applied to detect dried green, black, and oolong teas irradiated between 0-10 kGy. Teas irradiated at 2.5 kGy and higher showed over 5000 photon counts/60 sec, while non-irradiated teas yielded 650-1000 photon counts/60 sec. TL glow curves for minerals separated from teas were detected at about $300^{\circ}C$ with low intensity in non-irradiated samples, whereas around $150^{\circ}C$ with high intensity in all irradiated samples. Ratio of $TL_1/TL_2$ based on re-irradiation step, showing lower than 0.1 and higher than 1.44 for non-irradiated and irradiated samples, respectively, enhanced reliability of TL results. ESR measurements for irradiated teas showed signals specific to irradiation. Log DEFT/APC ratio increased with irradiation dose; this result could be applied to identify irradiated tea samples.

• 한국수산과학회지
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• 제47권5호
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• pp.489-494
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• 2014

This study determined the effect of packaging and electron beam irradiation on the quality of dried Undaria pinnatifida. Samples were air or vacuum packaged and irradiated at 7 kGy. The dried Undaria pinnatifida had total viable cells and coliform counts of 5.51 and 4.40 log CFU/g in total, respectively, and counts of 5.56 and 4.19 log CFU/g in surface. These counts were reduced by 2-4 log cycles after irradiation. Irradiation increased the lightness and yellowness of the dried Undaria pinnatifida, but not the redness. In the sensory evaluation, there were no significant differences among samples. Therefore, electron beam irradiation improves the microbial safety and quality of dried Undaria pinnatifida.

• Preventive Nutrition and Food Science
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• 제11권1호
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• pp.73-77
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• 2006

Ground pork was irradiated with an electron beam (e-beam) at a dose of 0, 1.5, 3, 5 and 10 kGy and the changes in various functional and other associated properties of salt-soluble proteins extracted from the pork were evaluated. Irradiation did not affect turbidity and the disulfide content of pork salt-soluble protein, but the content of sulfhydryls and the hydrophobocity of salt-soluble protein increased. This indicates that protein degradation occurred when the pork was e-beam irradiated and that the sulfhydryls and hydrophobic moieties buried inside the proteins were exposed to the outside environment. However, these degraded protein molecules did not form large protein aggregates through disulfide bridges. The emulsifying capacity of the pork increased with irradiation, which could be the result from increased hydrophobicity of pork salt-soluble protein. Water holding capacity of pork was not affected bye-beam irradiation.

• 한국축산식품학회지
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• 제29권5호
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• pp.573-578
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• 2009

This study examined the effect of gamma irradiation on shelf-life extension and sensory characteristics of dak-galbi. Commercial dak-galbi sauce was gamma-irradiated at 0, 5, 10, 15, 20, 25, and 30 kGy. The dak-galbi sauce (200 g) was then added to diced chicken (800 g) for cooking, and the cooked dak-galbi samples in vacuum bags were stored at $35^{\circ}C$ for 5 d. Dak-galbi samples were analyzed on d 0, 1, 2, 3, 4, and 5 for microbial analysis (plate count agar), thiobarbituric acid (TBARS) and volatile basic nitrogen (VBN) measurements, and on d 0 for sensory evaluation. On d 0, total bacterial populations were below detection limit after dak-galbi marinated with the gamma-irradiated (${\geq}15\;kGy$) sauces were cooked, and the samples marinated with higher dose irradiated dak-galbi sauce had lower (p<0.05) bacterial populations during storage. TBARS values of the dak-galbi samples marinated with non-irradiated sauce were not different ($p{\geq}0.05$) with those marinated with irradiated sauces on d 0, and the TBARS values increased (p<0.05) during storage at $35^{\circ}C$, regardless of irradiation dose. In the VBN analysis, there was no difference ($p{\geq}0.05$) in VBN values among irradiation doses on d 0, but VBN values decreased (p<0.05) as irradiation dose increased during storage. Moreover, there were no significant differences ($p{\geq}0.05$) in sensory characteristics among irradiation doses. These results indicate that use of gamma irradiation on dak-galbi sauce may be useful in shelf-life extension without compromising the sensory characteristics of dak-galbi.

• 한국축산식품학회지
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• 제30권4호
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• pp.603-608
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• 2010

This study investigated the effects of electron beam irradiation on pathogens, quality, and functional properties of shell eggs during storage. A 1st grade 1-d-old egg was subjected to electron beam irradiation at 0, 1, 2, and 3 kGy, after which the number of total aerobic bacteria, reduction of inoculated Escherichia coli and Salmonella Typhimurium, egg quality, and functional properties were measured. Electron beam irradiation at 2 kGy reduced the number of E. coli and S. Typhimurium cells to a level below the detection limit (<$10^2$ CFU/g) after 7 and 14 d of storage. Egg freshness as measured by albumen height and the number of Haugh units was significantly reduced by 1-kGy irradiation. The viscosity of irradiated egg white was also significantly decreased by increased irradiation, whereas its foaming ability was increased. Electron beam irradiation also increased lipid oxidation in egg yolks. These results suggest that electron beam irradiation reduces the freshness of shell eggs while increasing the oxidation of egg yolk and improving important functional properties such as foaming capacity. Electron beam irradiation can also be applied to the egg breaking process since the irradiation reduces the viscosity of egg white, which can allow egg whites and yolks to be separated with greater efficiency.

• 한국식품과학회지
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• 제31권1호
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• pp.7-12
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• 1999

우지에 항산화제로 ascorbyl palmitate (AP), ${\alpha}-tocopherol\;({\alpha}-Toc)$, BHA 및 ascorbyl $palmitate+{\alpha}-tocopherol\;(AP+{\alpha}-Toc)$을 첨가하여 $0{\sim}10\;kGy$의 선량으로 감마선을 조사하였고, 감마선 조사된 시료는 조사직후와 $50^{\circ}C$에서 저장하면서 저장기간에 따른 과산화물 형성 억제능을 측정하였다. 감마선 조사직후의 과산화물가는 감마선 조사선량의 높아짐에 따라 증가하였다. 그러나 우지에 항산화제를 첨가한 경우에는 감마선 조사에 의한 과산화물 형성을 억제하였고, 억제 활성은 $AP>BHA>AP+{\alpha}-Toc>{\alpha}-Toc$로 AP가 초기산화 억제능을 가진 천연항산화제로 나타났다. 저장기간에 따른 과산화물가는 감마선 조사에 의해 자동산화를 상당히 촉진시키지만 항산화제를 첨가한 경우에는 과산화물 형성을 유의적으로 억제하였으며, 이때의 항산화능은 $BHA>AP+{\alpha}-Toc>{\alpha}-Toc>AP$의 순으로 나타났다. 특히 저장말기까지도 효과가 높았던 천연 항산화제 혼합물인 $AP+{\alpha}-Toc$은 BHA와 유의차가 인정되지 않았다(p>0.05).

• Preventive Nutrition and Food Science
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• 제1권1호
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• pp.16-22
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• 1996

Amino acids and ribonucleotides were measured for boiled-dried anchovy to determine the effect of 5 kGy γ-irradiation on its quality stability during storage at ambient and cooling (5∼10℃) temperatures for 12 months in a laminated-film package(Polyethylene 10㎛). The anchovy samples contained about 55%(d.b) of total amino acids and about 1%(d.b) of free amino acids. Although there found a significant change(p<0.01) in the content of leucine and lysine immediately sfter irradiation, the overall content of toral amino acids was little changed in stored anchovy even six months after irradiation at cooling conditions. γ-Irradiation caused a significant reduction(p<0.01) in the total content of free amino acids, showing a similar tendency by storage conditions. However, the ribonucleotides. which were 12.00mg/g(d.b) in inosine-5'-monophosphate and 0.38mg/g(d.b) in guanosine-5'-monophospate, were resistant to 5kGy-irradiation. With the lapse of storage time, it was also shown that storage temperature was more influential than irradiation on the contents of amino acids and taste compounds of dried anchovy.