• Korean Journal of Food Science and Technology
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• v.33 no.6
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• pp.693-699
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• 2001

ChlorophyII destruction by irradiation in linoleic acid in methanol system was studied. ChlorophyII b standard (3 ppm) was added into methanol solution containing 1% of linoleic acid, and the sample was irradiated up to 20 kGy with or without nitrogen gas-bubbling. The content of chlorophyII b was analyzed by HPLC, and Hunter color value and UV-visible spectra were analyzed during 6 hr of photooxidation. The content of chlorophyll was reduced by irradiation and completely destroyed at 2.517 kGy. The model system with nitrogen gas-bubbling did not develop the lipid oxidation after irradiation or photooxidation at 20 kGy UV-visible spectra showed decreasing values of optical density by increase of irradiation doses, supporting the destruction of chlorophyII b. The results indicate that irradiation technology can be applied to reduce or eliminate the residual chlorophyII and to prolong the shelf-life of oil products.

• Applied Biological Chemistry
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• v.38 no.5
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• pp.425-430
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• 1995

The effects of oxidation stability and flavor acceptability of soybean oil by roasting and refining treatment were investigated in this study. The peroxide values of crude oil from unroasted soybean(COUS) were more increased than those of crude oil from unroasted soybean(CORS) during storage under fluorescence light at $45^{\circ}C$. Induction time by the Rancimat Method was 44.9 and above 88.7 hours on COUS and CORS respectively. The order of oxidation stability of oil was crude>degummed>alkali-refining>deodorized>bleached oil in terms of peroxide value, while that of oxidation stability of oil was crude>degummed>deodorized>alkali-refining>bleached oil in regard to induction time by the Rancimat Method. The correlation coefficients between induction time and two charateristics(absorbance of browning reaction products and phosphorous contents) were highly significant, while that between induction time and tocopherol contents was not high during refining stages. The scores for the sensory evaluation of flavor on sesame oil and CORS was 9.269 and 8.269 respectively, but it was not significant between two oils.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.11
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• pp.1767-1775
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• 2013

The purpose of this study is to investigate the total polyphenol and antioxidant activities of radish buds (Raphanus sativus L.) based on sprouting periods and extraction solvents in order to present basic data that are needed for using the radish buds as functional food material. The antioxidant activities were assessed by using various antioxidant models (DPPH, TBARS, Rancimat method, POV). The total polyphenol contents according to the extraction solvents were 84.11 and 296.51 mg/g, and the ethanol extract on day 4 of showed the highest value as 296.51 mg/g. As for DPPH radical-scavenging activity, on the day 4 of sprouting, water extracts indicated the highest scavenging activity by 86.67%, and the acetone extracts indicated a rather low scavenging activity as 77.23%. As for TBARS measurement of the radish bud extracts on day 4 of sprouting the extract of 70% ethanol was highest (71.48%). On day 8 of sprouting the TBARS value was increased and the methanol extract was highest (78.99%). As for the oxidative induction period on day 4 of sprouting in Rancimat measurement, the methanol extract was highest (6.07 hours) on day 4 and the antioxidant index was 1.16. On day 12 of sprouting, the general oxidative induction period tended to be reduced to 5.25 to 5.91 hours. In the peroxide value measurement on day 4 of sprouting and beginning of the storage, the extracts showed no difference between 3.02 meq/kg oil and 4.12 meq/kg oil, and on the day 60 of storage, the water extract (43.83 meq/kg oil) and the methanol extract (45.42 meq/kg oil) were lowest with higher antioxidant effect. In conclusion, the radish bud extract with higher total polyphenol contents and antioxidant activities may serve as functional material for food additives, such as natural antioxidants and food preserving agents.

• Korean journal of food and cookery science
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• v.24 no.6
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• pp.811-817
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• 2008

The principal objective of this study was to evaluate the effects of baking method on the quality and shelf-life of Maejakgwa containing nuts and seeds. Four different types of nuts and seeds (almond, cashewnut, coconut, and sunflower seed) were added to flour, and baking method was applied to prepare the Maejakgwa, physicochemical properties of which were then evaluated. The proximate composition analysis demonstrated that crude protein, crude fat, and ash contents were higher in the Maejakgwa containing nuts and seeds than in the control group. The lightness (L) value of the control Maejakgwa was lower than that observed in the groups containing nuts and seeds. Maejakgwa made with cashewnut, coconut, and sunflower seed evidenced higher yellowness (b) values than were recorded in the control and coconut groups. The incorporation of cashewnut, coconut and sunflower seed into the Maejakgwa lowered the hardness values (p<0.05). Our consumer test demonstrated that Maejakgwa prepared with almond was the most highly preferred, and the control group was the least favored. After 30 days of storage at $60^{\circ}C$, the peroxide value of the Maejakgwa containing sunflower seed was substantially higher than in any other groups, thereby suggesting that the addition of sunflower seeds resulted in accelerated lipid oxidation. No noticeable changes in peroxide values were observed in the groups prepared with coconut and cashewnut during storage time. The acid value increased with increasing storage time, and the addition of sunflower seed evidenced the highest values as compared to other groups.

• Food Science and Preservation
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• v.11 no.1
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• pp.126-129
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• 2004

To elucidate the effect of various natural antioxidants on the safflower oil, rosemary extract, green tea extract, isoflavon, Phaffia rhodozyma extract, tocopherol, sesamol, and BRA as a control were added to the safflower oil and stored at 60$^{\circ}C$ for 4 weeks. During storage, its viscosity and antioxidative activity were determined. Viscosity of the oil increased with increasing storage period and was related with its antioxidative acvtivity. Antioxidative avtivity among antioxidants used in this study were in order of green tea extract>BHA>tocopherol>rosemary extract>isoflavon>sesamol>Phaffia rhodozyma extract. Green tea extract was the best in terms of antioxidative acvtivity. After 4 weeks, its peroxide value decreased up to 80.4％ of the control, and 42.1％ for acid value and 47.4％ for TBA value decreased.

• Korean Journal of Food Science and Technology
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• v.29 no.3
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• pp.407-411
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• 1997

Effects of heating time and storage temperature on the oxidative stability of heated palm oil were studied. Palm oil was heated at $150^{\circ}C$ for 0, 1, 10 or 20 min and stored at 4, 20 or $65^{\circ}C$. The oxidative stability of the sample was evaluated by determining peroxide value of the oil and measuring the volatiles in the headspace of the sample. Significant difference in the peroxide or volatile formation was observed (p<0.05) in heated palm oils between samples stored at 4 or $20^{\circ}C$ and those stored at $65^{\circ}C$. Pentane, hexanal, heptane and total volatiles increased with heating time, while storage temperature did not significantly affect their formation, indicating that heating time played more important role in volatile formation in the heated palm oil than storage temperature. However, adverse results were observed for the formation of peroxide. The interaction effect of heating time and storage temperature on the oxidative stability of heated palm oil was also observed.

• Proceedings of the Korean Society of Food and Cookery Science Conference
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• 2003.10a
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• pp.87-87
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• 2003

정향을 물, 메탄올, 에테르로 각각 추출하여 각 추출물별로 총페놀함량, 전자공여능(electron donating ability, EDA), 과산화물가와 에멀젼 시스템에서의 항산화효과를 비교, 검토하였다. Follin-Dennis법으로 구한 물, 메탄올 및 에테르 추출물의 총페놀 함량은 각각 2.34, 6.98, 5.83 mg/100g으로 메탄올 추출물에서 가장 큰 함량을 보였다. 정향의 물, 메탄올 및 에테르 추출물의 전자공여능은 각각 86%, 78%, 68%이었다. 리놀레인산 기질에서의 항산화효과는 메탄올 및 에테르 추출물에서 높게 나타난 반면, 에멀젼 시스템에서는 물 추출물이 가장 우수한 것으로 나타났다. (중략)

• Proceedings of the Korean Society of Veterinary Pathology Conference
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• 2001.09a
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• pp.24-24
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• 2001

양어용 사료로 사용되는 생어사료(고등어, 전어, 새우) 및 배합사료에 대한 방사선 조사(5 kGy) 후 조성분의 변화와, 사료의 방사선 조사에 의한 산패정도 및 BHA (200 ppm)의 효과를 저장온도 (2$0^{\circ}C$, 4$^{\circ}C$, -2$0^{\circ}C$) 및 저장기간 (0, 3, 7, 14일)에 따라 측정하였다. TBA가 및 과산화물가를 산패도 측정에 적용하였다. 5 kGy의 방사선 조사에서 사료의 조성분은 변화되지 않았다. 방사선 조사에 의한 초기 산패는 증가되었으며, BHA첨가에 따라 양어용 생어사료의 자연산패 및 방사선에 의한 초기산패는 억제되었으며 (p<0.05) 농림부에서 고시된 사료의 공정규격의 미량첨가 사료의 사용제한 범위 (300 ppm)내 에서도 충분한 산패억제 효과를 나타냈다.

• The Korean Journal of Malacology
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• v.14 no.2
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• pp.103-111
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• 1998

참굴에 다환성방향족탄화수소(PAHs)의 축적성과 이 물질들이 미치는 독성을 평가하기 위해 해양환경에서 빈번히 검출되는 PAHs 중의 하나인 fluoranthene을 사용한 모델연구를 수행하였다. Fluoranthene을 0.01-1ppm의 농도로 2주간 참굴에 노출시켰을 때 참굴 조직내의 fluoranthene의 농도는 노출기간 및 노출농도에 비례하여 최고 40-70배까지 증가하였다. 소화맹낭과 폐각근의 지질 과산화물가는 노출기간 및 노출농도에 관련하여 현저히 증가하였으며 수용성단백질의 함량은 노출기간이 길어짐에 따라 서서히 감소하였다. 그러나 glycogen 함량, nucleoside/nucleotide, DNA 및 RNA 함량은 변화하지 않았다. 이 결과로 fluoranthene은 굴의 조직내로 원활하게 축적함을 확인하였다. 또한 과산화지질의 함량은 fluoranthene에의 오염에 대해 신속히 반응하는 지표의 하나로 추정되며 수용성단백질의 감소도 비록 시간적으로 다소 둔감하기는 하나 또 다른 지표가 될 수 있을 것으로 사료된다.

• The Korean Journal of Malacology
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• v.14 no.2
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• pp.113-120
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• 1998

참굴에 다환성방향족탄화수소(PAHs)의 축적성과 이 물질들이 미치는 독성을 평가하기 위해 해양환경에서 빈번히 검출되는 PAHs 중의 하나인 anthracene을 사용한 모델연구를 수행하였다. Anthracene을 0.01-1ppm의 농도로 2주간 참굴에 노출시켰을 때 참굴 조직내의 anthracene의 농도는 노출기간 및 노출강도에 비례하여 최고 25-85배까지 증가하였다. 소화맹낭과 폐각근의 지질 과산화물가는 노출기간 및 노출농도에 관련하여 현저히 증가하였으나 수용성단백질, glycogen, nucleoside/nucleotide 및 핵산의 함량은 변화하지 않았다. 이 결과로 anthracene은 굴의 조직내로 원할하게 축적됨을 확인하였으며 과산화지질의 함량은 anthracene에의 오염에 대한 예민한 생화학적 지표가 될 수 있을 것으로 사료된다.