• Food Science and Preservation
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• v.14 no.6
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• pp.624-632
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• 2007

Changes in proximate composition, amino acid, free sugar, reducing sugar and vitamin contents of Curcuma longa L. (autumn woolgeom in Korean) and Curcuma atomatica Salib (spring woolgeom) were investigated according to picking time. Moisture, crude ash, crude protein and crude lipid were increased and non nitrogen substances was decreased by extending the picking time. Contents and ratio of total amino acid to essential amino acids was increased by extending the picking time. Free amino acid was increased by extending the picking time. Ratio of essential amino acids to total amino acids was decreased. Fructose was gradually increased, and then glucose, sucrose and total free sugars were decreased by extending the picking time. Amino acid and sugar contents of Curcuma longa. L. were higher than those of Curcuma atomatica Salib. In contents of vitamin C and $B_1$, Curcuma longa L. was decreased and Curcuma atomatica Salib was increased by extending the picking time.

• 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.

• Korean Journal of Food Science and Technology
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• v.13 no.2
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• pp.107-113
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• 1981

Free sugars were isolated from ginseng root and its products and analyzed by using high performance liquid chromatogrphy. To isolate free sugars from aqueous sample solution fat-soluble components, crude saponin and protein were removed from the solution by extracting with benzene, water-saturated butanol and 80% ethanol, respectively. Free sugars found from both ginseng root and its products were fructose, glucose, sucrose and maltose, and the only sugar detected from red ginseng root and its products was rhamnose. Major sugar detected from fresh ginseng and white ginseng roots was sucrose, while sucrose and maltose were major sugars of red ginseng root.

• Korean Journal of Food Science and Technology
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• v.21 no.5
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• pp.633-638
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• 1989

The changes of free sugars in Kimchi during fermentation were analyzed by GC. The major sugars in Kimchi were mannose, fructose, glucose, and galactose and they were reduced gradually with fermentation, whereas mannitol appeared in the middle stage of fermentation and reduced slowly. The presence of mannitol in Kimchi was identified by GC and GC/MS for the first time. Most of free sugars were stemmed from chinese cabbage and radish, and reduced with fermentation. These patterns of change of free sugars were almost the same in Kimchi. It could be concluded that regardless of kinds of Kimchi the fermentation mechanism of Kimchi was very similar on the basis of the changes of free sugars.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 1998.04a
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• pp.38-38
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• 1998

• Food Science and Preservation
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• v.13 no.5
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• pp.581-588
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• 2006

Dynamic changes of free sugar and amino acid in the mixture of red bean paste sediment by corn syrup concentration and heating conditions were monitored. Glucose and fructose contents of red bean paste increased with an increasing blown color intensity. Amino acid content was affected by the heating temperature, increased with an increase in browning color intensify. Browning color intensity of each samples increased up to $95^{\circ}C$, but decreased above $95^{\circ}C$. This result was the same tend as changes of glucose and amino acid. The result of correlation coefficients among free sugar amino acid and browning color intensity show that increase in browning color intensity was not correlated directly with changes of free sugar and amino acid content. It seems that the contents of free sugar and amino acid resolved from saccharides and protein were much mote than contents nea for browning reaction.

• 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.

• Journal of the Korean Society of Food Science and Nutrition
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• v.16 no.4
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• pp.323-327
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• 1987

The sugar contents of Dolwoe, which were prepared in the laboratory and marketed Korean products of Dolwoe, Japanese product of Dolwoe and Korean-roasted products of Dolwoe were analyzed and compared. The contents of total sugar and reducing sugar of stem in prepared Dolwoe tea were 2 times higher than those of leaf. The sugar content of Korean product was similar to that of Japanese, but the contents of total sugar and reducing sugar in Korean-roasted sample decreased to 17.2% and 40.9%, respectively. It was confirmed that free sugar in Dolwoe tea was composed of rhamnose, fructose, glucose and sucrose. The ratio of free sugar content was quite different between Dolwoe-leaf tea and Dolwoe-stem tea. Comparing the free sugar content in prepared Dolwoe tea, glucose was the highest followed by fructose, sucrose and rhamnose. On the other hand, in marketed Dolwoe tea, glucose was the highest substance and followed by fructose, rhamnose and sucrose. It was found that rhamnose content in Japanese product was approximately 6 times more than that of Korean.

• Korean Journal of Food Science and Technology
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• v.16 no.1
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• pp.7-10
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• 1984

The three kinds of Kochujang were prepared with liquid koji equivalent to 30%, 50% and 70% of brewing water and the contents of free amino acids and free sugars during aging at $25^{\circ}C$ for 3 months were compared with those of the control group which was made from solid koji. All tested Kochujang were higher in glutamic acid, lysine and aspartic acid while lower in methionine, histidine and tryptophan. The content of total free amino acids was high in the order of control group, 70%, 50%, and 30% liquid koji group. Fructose and rhamnose were found in all groups, but glucose in only the control group and 70% liquid koji group. Fructose content was the highest of the free sugars and total free sugar content was higher in the control group and 70% liquid koji group than other groups.

• Korean Journal of Food Science and Technology
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• v.17 no.6
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• pp.442-446
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• 1985

The changes of nitrogen utilization ratio (NUR), Protein solution ratio (PSR) and free sugar contents during the amino acid soysauce manufacturing process by a low hydrochloric acid, temperature were investigated. On hydrolysis by 6%-HCI (3 liquor rate of defatted soybean weight, 3LR) at $85^{\circ}C$, NUR and PSR were 74.51%, 56.49% at 65 hours. At the same time free sugars were detected glucose, galactose, arabinose, fructose, xylose. on hydrolysis at $95^{\circ}C$, NUR and PSR were 77.72%, 64.04% at 50 hours, and 5 free sugars of the above statement were detected at 5 hours. Remarkable decreases in the levels of free sugars, only glucose were observed after 80 hours of the hydrolysis. On hydrolysis by 12%-HCI(3LR) at $95^{\circ}C$, NUR and IRA were 88.41%, 69.47% at 50 hours, free sugar were nearly disappeared after 20-35hours. On hydrolysis, galactose's disappearence rate was faster than glucose's.