• Food Science and Preservation
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• v.10 no.4
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• pp.488-492
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• 2003

This study was analyzed to the components of leaf teas produced by manufature methods for which estimated food and nutritional values of Lindera obtusiloba loaves growed in Korea and had unique taste and aroma. There were identified to four kinds of free sugars in Lindera obtusiloba leaf teas and its content was the highest in the roasted tea among others. The contents of glutamic acid, aspartic acid, asparagine, and glycine were remarkably higher than other amino acids. The contentsof free amino acid in the leased tea and the androasted tea after steaming wase. 6 mg/100g had 101.5 mg/100g, respectively,had especially higher than in the others. Among the amino acid derivativer, phosphoserine, ${\alpha}$-aminobutyric acid, ${\beta}$-aminobutvic acid, and anserine contents were especially higher than others, but were not significantly difference by the manufacturing process. The volatile organic acids were composed acetic, propionic and butyric acid, and the nenvolatility organic acid were composed citric, oxalic, levulinic glutaric, lactic and pyroglutamic acid.

• Korean Journal of Food Science and Technology
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• v.27 no.1
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• pp.36-40
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• 1995

Yam(Dioscorea) tubers were used as one of the dietary starches in Korea, China and Japan because of its characteristic properties. Yam tubers were powdered after freeze drying the sliced tubers to investigate carbohydrates. Chemical properties such as proximate components and carbohydrates were studied using three varieties of Korean yams, namely. D. batatas, D. aimadoimo and D. japonica. The proximate components of yam tubers showed that the major components of Korean yam tubers were carbohydrates and moisture. The main components of free sugars in yams were identified as fructose, glucose, sucrose and maltose. In addition to these four sugars, there were two unidentifiable peaks whose areas are too big to ignore. These results were obviously different from other reported data of free sugars in yams. The main components of total sugars were mannose and glucose.

• Journal of Bio-Environment Control
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• v.10 no.4
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• pp.244-250
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• 2001

This study was conducted to determine the change in freezing tolerance of Chinese cabbage (Brassica campestris L. ssp. penkinensis). Four-week old seedlings grown in a greenhouse at $25^{\circ}C$$\pm$0.5 were transferred to 5, 10 or 15$^{\circ}C$ condition for acclimation for one day, and then transferred to a lethal temperature of -3$^{\circ}C$ condition. Optimal acclimation temperatures were 5$^{\circ}C$ and 1$0^{\circ}C$. Freezing tolerance of leaf tissues was investigated during a week-long cold stress. Development of freezing tolerance was shown by survival ratio, and amounts of total RNA, soluble protein and soluble sugar. LT$_{50}$ value increased from -3 to -4$^{\circ}C$ after 5 days acclimation at 5 or 1$0^{\circ}C$, and this was considered to be the first indication of enhanced freezing tolerance. Plants, cold acclimated for five days, reached to a survival ratio of 60%. This increase in freezing tolerance was found to be associated with the increased levels of total RNA, soluble sugar and soluble protein. These metabolic changes imply the association of adjustment of growth and cell metabolism with low temperatures at the beginning of cold acclimation in chinese cabbage.e.

• Food Science and Preservation
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• v.9 no.2
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• pp.205-211
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• 2002

In order to selection of the suitable soybean varieties, the quality characteristics of meju and doenjang on 4 domestic soybean cultivars(Daeweon, Sodam, Jinpeum and Hwangkeum) were evaluated. Crude protein and lipid content was 26.7∼30.5% and 16.89∼19.31%. The content of total free sugar among 4 soybean cultivars were 4.99∼5.26% and composed mainly stachyose(2.59∼3.51%), raffinose and sucrose. The content of total free sugar of meju were the highest in Jinpeum among 2.10∼2.66% and composed mainly glucose. The lightness of meju lump in Hwangkeum was larger decrease than the others, the redness were higher in Daeweon and Hwangkeum, the yellowness was the highest in Sodam. The lightness of meju powder was the highest in Sodam, the redness was the lowest in Sodam, the yellowness was the highest in Hwangkeum. The chemical composition of doenjang were that : was the highest in Jinpeum among the 7.90∼9.71% crude lipid, in Daeweon among 9.67∼13.50% crude protein, in Sodam among 2739∼3825 mg% Formol nitrogen and in Daeweon among 6.88∼8.36% crude saponin, respectively. The content of total free sugar of doenjang were the highest in Hwangkeum among 1.88∼2.22% and composed mainly fructose and glucose. The lightness and yellowness of doenjang was the highest in Sodam, the redness was the highest in Hwangkeum. Doenjang by Hwangkeum had good score for taste, texture and overall quality in sensory evaluation.

• Korean Journal of Food Science and Technology
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• v.28 no.6
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• pp.1095-1103
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• 1996

In order to minimize the deterioration of dried apple quality, changes of free sugar content, organic acid and ascorbic and during osmotic dehydration with sucrose at various temperature, concentration and immersion time were investigated in this study, total sugar increased as the temperature, concentration and immersion time were increased. Sucrose showed the largest change in content while fructose and glucose showed no and small changes, respectively. Large amounts of malic and fumaric acids, and small amounts of oxalic, citric, maleic and succinic acids were detected. Organic acids were high at low temperature treatment, and became higher with increasing concentration. Loss of ascorbic acid was small at the low temperature and high concentration. Effect of immersion time was negligible. Changes of free sugar, and organic and ascorbic acid followed the first-order and second-order reaction rate equations, respectively. Arrhenius equation was applied to determine the effect of temperature on reaction rate constants with high $r^2$. To predict the changes of quality, a model was established by using the optimum functions of temperature, concentration and immersion time. The model had high $r^2$ value for the quality changes during drying.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.3
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• pp.267-275
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• 2003

To observe the effects of seed matriconditioning on the emergence, plumule growth, and seed physiological properties of normal and aged seeds of three corn(Zea mays L.) genotypes (dent, sugary, and shrunken-2), normal and artificially aged seeds were matriconditioned at 50, 75, 100, and 125% moisture contents of vermiculite at $25^{\circ}C$ for 24 hours and the germinability was examined at $25^{\circ}C$ and in cold test (7 days at 1$0^{\circ}C$followed by $25^{\circ}C$). Emergence rate, emergence speed, and plumule growth were smaller in the order of dent＞sugary＞shrunken-2. Matriconditioning did not affect the emergence rate of normal dent and sugary seeds, while it enhanced emergence speed and plumule growth. In contrast, the emergence rate, emergence speed, and plumule growth of normal shrunken-2 and aged seeds of all genotypes were enhanced as the moisture content of vermiculite increased up to 125% both at $25^{\circ}C$ and in cold test. Matriconditioning promoted $\alpha$-amylase activity and DNA and soluble protein contents, while it reduced the leakage of total sugars and electrolytes from the seeds when soaked in water.

• Analytical Science and Technology
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• v.10 no.5
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• pp.362-369
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• 1997

Chemometric technique was applied to the sugar composition in five honeys of known botanical or geographical origin following HPLC. Fructose and glucose were predominant carbohydrates in honeys, and small amount of sucrose was also detected in one sample. Sugar contents in honeys samples were compared by the geographical or botanical origin. Fructose/glucose ratio ranged from 0.99 to 1.55 was obtained and these results are in good agreement with the ratio of literature. The plot of principal components analysis(PCA) showed that different honey samples grouped into distinct cluster by the geographical or botanical origin. Increasing the first or second principal component score, higher amount of sugar or less fructose/glucose ratio was observed in PCA plot. Chemometric approach was very useful to provide pattern recognition of sugar profile or quality indices of honey sample and to detect adulteration.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.7
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• pp.879-885
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• 2008

This study was conducted to analyze 15 traditional Korean gruels for nutrient density using the Index of Nutrient Quality (INQ). The calorie of the gruels ranged from 148.8 (Daechujuk) to 294.1 kcal (Jatjuk) per serving size. The calorie in 'Jatjuk' was the highest, covering 33.3% of Dietary Reference Intakes for Koreans (KDRI) per meal. The carbohydrate content was between 23.0 g (Dakjuk) and 52.1 g (Patjuk) per serving size. The average content of carbohydrate in gruels was $34.7{\pm}9.1\;g per serving size which covers 24.4% of KDRI per meal. Among the 15 gruels, Patjuk contained the highest carbohydrate content (52.1 g per serving size, 36.7% of KDRI per meal). The highest nutrient density (INQ) of carbohydrate in gruels was Dachujuk (INQ 1.4). The protein content of the gruels was between 2.3 (Huinjuk) and 22.3 g (Dakjuk) per serving size. The average content of protein in gruels was 25.6% of KDRI per meal. Dakjuk contained the highest protein content ($8.2{\pm}4.9\;g$ per serving size) and followed by Dakjuk (INQ 2.5), Guljuk (INQ 1.5) and Kongjuk (INQ 1.3) in nutrient density (INQ) of protein. The fat content of the gruels were between 0.3 (Daechujuk) and 17.8 g (Jatjuk) per serving size. The average content of fat in gruels was $17.8{\pm}0.12\;g$ per serving size which showed 21.1% of KDRI per meal. Among the gruels, Jatjuk contained the highest fat ($17.8{\pm}0.12\;g$ per serving size, 77.4% of KDRI per meal). In order of the high nutrient density (INQ) of protein, Jatjuk (INQ 2.4) was followed by Heugimjajuk (INQ 1.5) and Kongjuk (INQ 1.5).

• Food Engineering Progress
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• v.13 no.4
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• pp.235-242
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• 2009

The purpose of this study is to establish fundamental research data for quality characteristics of Jochung by analyzing traditional manufacturing process. Two different processed rices (non-glutinous rices cooked by steaming and using an electronic rice cooker) were compared in terms of water solubility index (WSI), water absorption index (WAI), paste viscosity, reducing suger content, solid content, and dextrose equivalent over soaking time. Reducing sugar content increased for the soaked non-glutinous rice, steamed sample and microwaved sample. After 4 hr, the WSI decreased as the soaking time increased. However, there was no significant difference between WAI of the raw non-glutinous rice and the soaked non-glutinous rice. As soaking time increased, paste and breakdown viscosity increased significantly. Rice was prepared by soaking in water for 12 hr followed by the saccharification time (4, 8, or 12 h) for manufacturing Jochung. The solid content and reducing sugar content of the Jochung increased as the soaking time increased. Reducing sugar content and dextrose equivalent of Jochung from steamed rice (cooked hard) were higher than those from microwaved ones. The amount of reducing sugar and dextrose equivalent was highest in Jochung from steamed rice cooked hard (saccarification for 12 hr), with 59.40${\pm}$0.11% and 76.99${\pm}$1.78, respectively. In conclusion, the highest quality characteristics were obtained in Jochung manufactured with non-glutinous rice soaked for 12 hr followed by sacharification for 12 hr.

• Explosives and Blasting
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• v.18 no.3
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• pp.15-28
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• 2000

국내에서는 Heavy ANFO로 더 잘 알려져 있는 Emulsion Blends는 왁스 대신 오일을 사용 하여 상온에서 펌핑이 가능하도록 한 에멀젼과 ANFO(또는 초안)의 혼합물을 일컫는다. ANFO는 저렴하고 안전하며 장약이 쉽고 밀장전되는 장점이 있지만, 내수성이 거의 없고 폭발 속도가 느리며 장약 비중이 0.75∼0.90g/cc 정도로 낮아 폭약으로서 그 위력이 작은 단점을 갖고 있다. Blends는 수용성 ANFO 입자 사이의 빈 공간을 내수성 에멀젼이 태우고 있는 형태로서 에멀젼 함량 25%부터 내수성이 나타나기 시작하여 에멀젼 함량 40% 이상에서는 완전한 내수성을 갖게 되며, 에멀젼의 함량이 증가할수록 폭발속도는 카트리지 에멀젼 폭약에 근접하게 된다. 장약 비중은 에멀젼의 함량이 증가하여 45% 근처에서 1.25∼ 1.30g/cc의 최대 값을 갖지만, 그 이상의 에멀젼 함량에서는 기폭 감도 저하로 예감제를 사용하여 비중을 감소시키는 것이 바람직하다. Blends는 자체에 물을 함유하고 있으므로 열역학적으로 계산된 단위 중량당 반응열은 ANFO에 비해 매우 적지만, 폭발속도, detonation pressure(폭굉압), borehole pressure(폭발압력) 등이 ANFO에 비해 크므로 폭발압력에서부터 암석의 파괴가 가능한 압력가지의 단위 중량당 유효한 에너지의 양은 암석의 강도가 커질수록 ANFO에 비해 매우 적지만, 폭발속도, ANFO와 비슷해진다. 따라서 장약 비중이 ANFO의 130∼145%로 높은 Blends는 동일한 천공에 더 많이 장약할 수 있어 단위 천공당 암석 파괴에 이용되는 유효 에너지의 총 양이 커지게 되므로, 공간격과 저항선을 늘릴 수 있어 총 천공수를 감소시킬 수 있다. 결론적으로, Blends의 장점은 내수성과 함께 비장약량은 비슷하거나 약간 증가하는데 비해, 천공수는 크게 감소하여 전체적으로는 발파 현장의 경제성이 향상된다는데 있다.