• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.11
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• pp.1575-1581
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• 2011

Rapeseed cake, which is the organic waste remaining after rapeseed oil production, is readily available and considered an ecologically-friendly resource with very low cost and high dietary fiber content. This research was carried out for two reasons. First, it was done to analyze the liberated reducing sugar content of rapeseed cake. Second, it was done to investigate the effects on the sugar yield of the various concentrations of acidic and alkaline catalysts used for the hydrolysis of rapeseed cake and the concentrations of rapeseed cake in each catalyst. Several amounts of ground rapeseed cake, 0.5 g, 1 g, and 2 g, were put into 100 mL of catalysts such as sulfuric acid (0.5~2%), hydrochloric acid (0.5~2%), and sodium hydroxide (0.5~2%). Then they were hydrolyzed for 5 min at 121$^{\circ}C$. After hydrolysis, HPLC equipped with an RI detector was used to analyze liberated reducing sugars such as sucrose, glucose, galactose, fructose, and arabinose separated from rapeseed cake. The degradation rate of rapeseed cake was the highest in hydrochloric acid. As the catalyst concentrations used for hydrolysis of rapeseed cake increased, the degradation rate of rapeseed cake also significantly increased. Total reducing sugar content was the highest in hydrochloric acid, and it increased with the increase of catalyst concentrations. However, as the amount of rapeseed cake increased, the total reducing sugar content decreased, exceptionally sucrose in the case of sodium hydroxide.

• Applied Biological Chemistry
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• v.49 no.3
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• pp.209-214
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• 2006

Various varieties of mulberry fruit and wines were investigated to determine their chemical properties and fermentation characteristics. Mulberry wines were manufactured with 'Cheongnosang', 'Cheonhyunosang', 'Deokcheonsang', 'Hwachosipmunja', 'Hwanyoupdaeyoup', 'Jasan', 'Mansaengbaeckpinosang', 'Palcheongsipyung', 'Sabangso' and 'Susungppong'. The factors for wine fermentation and quality such as soluble solids, polyphenol and organic acids were analyzed. The contents of soluble solid, reducing sugar and polyphenol, which were affected significantly by each other, were higher for 'Hwanyoupdaeyoup', 'Jasan' and 'Palcheongsipyung' mulberry than other varieties. Organic acids such as citric, malic, succinic and acetic acid were detected in the mulberry fruits. 'Palcheongsipyung' mulberry fruit had a higher content of souble solids $(14.6^{\circ}Brix)$ and polyphenol compounds (2.15 mg/ml). After fermentation, 'Palcheongsipyung' mulberry wine showed the lowest acetic acid in 3.23 mg/ml and the highest citric acid in 12.3 mg/ml. From these results, 'Palcheongsipyung' mulberry fruit was the most suitable for the fermentation of mulberry wine.

• Horticultural Science & Technology
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• v.18 no.6
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• pp.808-810
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• 2000

The chemical components of xylem sap collected from kiwifruit (Actinidia chinensis Planch cv. Hayward) trees were analyzed and processing of xylem sap drink were accomplished to increase utilization of xylem sap as a drink. Water content, soluble solids, viscosity, and pH of the xylem sap were 99.60%, 0.90%, 1.01, and 6.50, respectively. In the xylem sap, fructose was the highest among free sugars followed by glucose, sucrose, galactose, and mannitol. The major inorganic components in the sap were calcium, potassium, and magnesium, and calcium was the dominant among them. Ten kinds of amino acids in the xylem sap were detected by amino acid analyzer, and the major amino acids were glutamic acid, lysine, and isoleucine. Glutamic acid was the most dominant amino acid in the xylem sap. Major compositions of xylem sap drink were 74.5% xylem sap, 15% kiwifruit puree and 10% high fructose. Nutritional facts in drink (252 mL) processed by using the xylem sap were 21.8 g sugar, 23.1 mg calcium, 14.1 mg potassium, 554.5 mg amino acid, and 15.6 mg ascorbic acid.

• 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.