• Proceedings of the Korean Radioactive Waste Society Conference
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• 2004.11a
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• pp.57.2-57.2
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• 2004

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2004.05a
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• pp.330-333
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• 2004

본 연구는 ${\beta}$-cyclodextrin 처리를 이용하여 우유에서 cholesterol을 제거하여 호상요구르트를 제조하고 혈중 콜레스테롤 저하 물질인 달맞이꽃 종자유(EPO)의 양을 다르게 첨가하여 호상요구르트의 저장기간 중 이화학적 변화와 물성 및 관능적 특성을 살펴보았으며, 그 결과 pH는 저장기간 15일이 경과함에 따라 모든 군에서 pH의 저하가 일어났고, 각 실험군 간 유의적 차이는 없었다. 마찬가지로 산도도 저장기간 15일이 경과함에 따라 모든 실험군에서 계속적인 증가가 나타났으며, 실험군간 유의적 차이는 없었다. 지방산화도측정결과 TBA가(535nm)는 저장 0일에 0.045에서 저장 15일에 0.196까지 증가하였고, EPO 첨가 호상요구르트는 0.188까지 증가하였으나 실험군간 유의적 차이는 보이지 않았다. 점도는 ${\beta}$-CD를 처리하여 2% EPO를 첨가한 호상요구르트가 저장 0일에 3.7에서 저장 15일에 8.4로 가장 큰 점도 감소를 나타내었고, 저장 15일 동안 모든 군에서 점도감소가 나타났다. 관능검사결과 ${\beta}$-CD처리하여 EPO를 첨가한 호상요구르트의 산패취와 산패한 맛이 control보다 높았지만 저장기간이 지날수록 점차 낮아졌고, 신맛과 쓴맛은 control과 유사하게 나타났다. 결론적으로 EPO를 첨가한 호상요구르트는 이화학적 변화와 물성 및 관능적으로 긍정적인 결과로 나타나 산업화의 가능성을 보였다.

• Korean journal of food and cookery science
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• v.15 no.5
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• pp.539-544
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• 1999

This study attempted to determine the effect of storage temperature(5$^{\circ}C$ and 25$^{\circ}C$) and time(1, 24, 48 and 72 hours) on the sensory and textural properties of mungbean starch gels. The color value, syneresis, texture and sensory properties of mungbean starch gels were measured. As the storage time increased, the lightness(L) and whiteness(W) values of mungbean starch gel increased. This trend was more apparent at the storage temperature of 5$^{\circ}C$. The syneresis of gels also increased as the storage time increased and the storage temperature was lower. As the storage time increased, the hardness of the gel increased whereas the adhesiveness and cohesiveness of the gel decreased. These results showed that mungbean starch gel lost its typical viscoelasticity during storage. This trend was also more apparent at the storage temperature of 5$^{\circ}C$. Sensory characteristics of the gel were well correlated with the mechanical characteristics. Overall quality of the gel decreased markedly at the 2nd day storage at 5$^{\circ}C$ and at the 3rd day storage at 25$^{\circ}C$.

• Journal of Animal Science and Technology
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• v.46 no.4
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• pp.635-644
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• 2004

This experiment was earned out to investigate the effects of dietary vitamin C and E on lipid oxidation and stability of color in Hanwoo steer beef. Thirty seven Hanwoo steers were randomly assigned to one of four treatments. The four treatments were control(vitamin E 20IU/kg feed), vitamin C(vitamin C 0.l%/kg feed and vitamin E 20IU/kg feed), vitamin E(vitamin E 220IU/kg feed) and vitamin C plus E(vitamin C 0.l%/kg feed and vitamin E 20IU/kg feed). Hanwoo steers were fed the experimental diets for 3 months at the last finishing period and pH, color, TBARS, concentration of myoglobin, water holding capacity, reduction by heat, drip loss and purge loss of longissimus dorsi were analyzed at 1, 3, 5, 7 and 10th day of storage, respectively. pH value, Hue angle, metmyoglobin concentration, TBARS, drip loss and purge loss in longissimus dorsi were increased as the storage period elapsed. However, water holding capacity in longissimus dorsi was decreased as the storage period elapsed. The animals fed the vitamin C plus E diet were higher in pH value and oxymyoglobin concentration, and lower in metmyoglobin concentration than in those fed the other diets during the whole storage period and lowest in TBARS. TBARS and Hue angle in longissimus dorsi were 10wer(P<0.05) in the animals fed the vitamin-supplemented diets than in those fed the control diet. Reduction by heat in longissimus dorsi was higher(P<0.05) in the animals fed the diets supplemented with vitamin E or vitamin C plus E than in those fed the control diet or vitamin C-supplemented diet. According to these results, it may be concluded that feeding the diets containing 0.1% vitamin C or 220IU vitamin E per kg feed or the diet mixed 0.1% vitamin C with 220IU vitamin E to Hanwoo steers can retard lipid oxidation of longissimus dorsi and stabilize beef color.

• Journal of the Korean Wood Science and Technology
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• v.41 no.4
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• pp.310-317
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• 2013

This research has been carried out to evaluate the durability characterization of larch wood used for woody erosion control dam. Wood deterioration and strength properties were analyzed according to installed position and duration. Optical and scanning electron microscope were used for examining wood deterioration, and an universal testing machine was applied for compression and shearing strength. As a result, deposited wood in water was maintained almost similar anatomical and physical properties compare to normal wood, even though it was used for seven years. In non-deposited wood which was installed on the side of the dam, heartwood did not show any significant change during seven years, while sapwood was significantly deteriorated in five years. Also, strength properties of sapwood were significantly decreased according to installed duration whereas, degree of decrease in heartwood were relatively smaller than that in sapwood.

• Journal of Labour Economics
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• v.25 no.1
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• pp.47-74
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• 2002

Since the Economic Crisis at the end of 1997, unemployment rate soared up to the record-high 8.6% (February 1999) and, for youth aged 15~29, it was 14.6% (27.8% for aged 15~19). In spite of economic recovery after the crisis, new participants in labor market at the school-to-work transition have faced with difficulties in finding their first jobs and, even further, the ratio of youth at out-of the labor force but not in school has remained at a higher level. It is important to calibrate the negative effects of nonemployment in the short-run as well as in the long-run, but there has been few study on the school-to-work transition in Korea. This study focus on the nonemployment duration to first job after formal education and comparison of its pattern before and after the crisis. A proportional hazard model, considering job prenaration before graduation (21.4% of the sample), with the semi-parametric baseline hazard is applied to the sample from the Korean Labor and Income Panel Survey(1998~2000) and its Youth Supplemental survey(2000). Interview of the Survey is conducted, by the Korea Labor Institute, to the same 5,000 household and 13,738 individual sample, guaranteeing nationwide representativeness. The Supplemental Survey consists of 3,302 young individuals aged 15 to 29 at the time of survey and 1,615 of them who are not in school and provide appropriate information is used for the analysis. The empirical results show that there exists negative duration dependence at the first three or for months at the transition period and no duration dependence since a turning point of the baseline hazard rate and that unemployment rate reflecting labor demand conditions has a positive effect on exiting the nonemployment state, which is inconsistent with a theoretical conclusion. Estimation with samples separated by the date of graduation before and after the crisis shows that the effect of unemployment rate on the hazard was negative for the pre-crisis sample but positive for the post-crisis sample.

• Food Science and Preservation
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• v.10 no.4
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• pp.454-458
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• 2003

This study was conducted to enhance the quality and peach (Yumyung) by ozone treatment. The ozone concentration and treatment time in soaking of peach were 0.1, 0.3 and 0.5 ppm and 30 min respectively. Fruit brix degree, titratable acidity, hardness, colors values, and rotten rate were determined in ripening grade Yumyung peach and when fruits were placed at ambient temperuture(25$^{\circ}C$) during 20 days. No great difference occured between control group and all ozone treatment samples in the changes of brix degree, titratable acidity, hardness and color values at my sampling period. However, the rotten rate of ozone-treated peach stored at 25$^{\circ}C$ was lower than that of control sample. The orders of rotten rate in peaches stored for 15 days at 25$^{\circ}C$ were control products > 0.1ppm ozone-treated > 0.3ppm ozone-treated) 0.5ppm ozone-treated. Therefore, optimal renditions of Yumyung peach stored by ozone treatment at ambient temperature during 20 days were ozone concentration of 0.5ppm, treatment time of 30min, and ozone treatment frequency of four times.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.59 no.4
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• pp.413-426
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• 2014

This study was conducted to investigate changes of physicochemical properties and fatty acid compositions of rough rice stored at different storage temperatures and periods. So we analyzed texture, alkali digestion value (ADV), toyo glossiness value, pasting properties, fat acidity and fatty acid compositions of five rice varieties every 4 month on the condition of which rough rice had been stored at different temperatures (ambient and low temperature condition at $15^{\circ}C$) for 2 years. Hardness of cooked rice was increased by storage periods and cohesiveness of cooked rice was not considerably different among varieties according to storage temperatures and periods. ADV was significantly different among varieties and storage periods but not different with storage temperatures. Toyo glossiness value of cooked rice was continuously decreased from 4 months after storage regardless to storage temperature. The pasting properties were considerably affected by storage temperatures and periods of rough rice. Increase in peak viscosity, final viscosity and breakdown was observed but setback was decreased by storage periods. Fat acidity of brown rice was much higher than that of milled rice during storage of rough rice and tend to increase by storage period. Oleic acid among fatty acids of brown rice except Sindongin and Hitomebore tended to be decreased by storage periods and linoleic acid among fatty acids of brown rice of Hopum was decreased by storage periods. The contents of linoleinic acid and stearic acid among fatty acids of milled rice were comparatively decreased from 4 months after storage, whereas the content of palmitic acid tended to be increased by storage periods.

• Korean Journal of Food Science and Technology
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• v.28 no.2
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• pp.220-225
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• 1996

Quarri green peppers were stored at $3^{\circ}C$ and $25^{\circ}C$, and capsaicin, ascorbic acid, chlorophyll, free sugars and surface color of the peppers were measured for 35 days of storage. Capsaicin and dihydrocapsaicin of quarri green peppers decreased during storage. The changes were bigger at $25^{\circ}C$ storage than at $3^{\circ}C$. Weight loss and decaying rate of the peppers were affected most by the increasing storage period and temperature. Ascorbic acid diminished remarkably at the beginning of storage period. Free sugars and chlorophyll decreased gradually during storage. Browning of quarri green peppers progressed slowly during storage not in pericarps but in seeds.

• Journal of Bio-Environment Control
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• v.19 no.4
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• pp.377-381
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• 2010

This study was carried out to access the stauts of pyruvic acid and sugars in onion bulbs during storage at room temperature. Pyruvic acid content remained in a steady state until 3 months of storage. However the pyruvic acid content gradually increased as the onions started to root, and rapidly increased after sprouting. There was no difference in dry matter contents during storage.e. Sucrose content increased as storage duration extended, and then gradually decreased right after the onions started to sprout. Fructose content gradually decreased after 45 days of storage, and remained in a steady state after sprouting. Glucose content had a tendency to increase as storage duration extended. Pyruvic acid/total sugar (PA/TS) ratio decreased after 1 month of storage, and then increased after 135 days, and was 83% higher at 150 days of storage than at harvest. Sweetness gradually decreased until 1 month of storage, but thereafter remained steady. Therefore it is desirable that pyruvic acid analysis for sweet onion selection should be conducted before breaking the dormancy.