• The Korean Journal of Food And Nutrition
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• v.10 no.4
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• pp.446-452
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• 1997

Sugars in Korean Kochuzang, saccharified and fermented red pepper paste, were studied by HPLC, TLC and NMR. The sugars in Kochuzang were extracted by heating in boiling water bath for 3 min. Commercial Kochuzang was found to contain 0.8~6.5% of limit dextrin, 0.3~7.3% of maltotriose, 5.3~16.5% of maltose, 8.6~29.4% of glucose and 0.3~3.4% of fructose, but did not found sucrose. The sugars in domestic Kochuzang were found to contain 2.3~1.5% of limit dextrin, 3.3~6.9% of maltotriose, 6.1~11.5% of maltose, 6.1~11.7% of glucose and 3.4~5.2% of fructose and 3.6~3.8% of sucrose. Limit dextrin in Kochuzang of maker 1 and 3 showed both signal of $\alpha$-1, 4- and $\alpha$-1, 6-glucosidic linkage with its estimation ratio of 5:1 and 9.1:1, respectively, by 1H-NMR analysis.

• Applied Biological Chemistry
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• v.27 no.3
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• pp.158-162
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• 1984

In order to estimate the basic data for the processing suitability of fruits, the contents of free sugars in citrus fruits(14 varieties) cultured in Jeju island, and peaches(4), grapes(4), pears(3) and apples(6) obtained from a local market were investigated by HPLC. The sucrose was the most abundant sugar in citrus fruits and peaches, and followed by fructose and glucose in order. The sugar contents in citru fruits was a wide difference according to the variety. In citrus fruit, the sucrose content was about 53 to 65% to total free sugars and the ratio of fructose to glucose was 1.0/0.8-1.1. The sugars present in grapes and pears were fructose of most abundance, glucose and sucrose in order. Jangshiprang pear showed 2 times higher fructose content than other variety. The free sugar in Taeyang and Hongok(Jonathan) apples were fructose, glucose and sucrose in order of abundance which fructose, sucrose and glucose in Golden Fuji and Mutsu.

• Korean Journal of Agricultural Science
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• v.41 no.2
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• pp.107-112
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• 2014

Coloring agents in food materials plays important roles in the development of attractive products as well as in the functionality of food such as antioxidant or vitamin supplementation. Carrot has been used as an orange coloring agent in the decoration of food but also a major source of vitamin A complex. Though orange has been considered a typical color of carrot, the Rainbow carrot has been developed recently, which exhibit the various colors such as red, pale yellow, purple, orange or their mixtures. After categorization onto 8 groups by their colors, vitamin A complex (${\beta}$-carotene, lycopene and lutein) and soluble sugars (glucose, fructose, and sucrose) have been analyzed in carrots. The ${\beta}$-carotene was abundant in the groups of orange (Group-O) or groups with the orange color (group-OP, and group-YOP). The content of lycopene content was exclusively high in the red color carrot (group-R). The highest lutein contents were observed from the yellow-purple (group-YP) group. Meanwhile, little amounts of lycopene and ${\beta}$-carotene were observed in yellow-purple (group-YP) nor yellow (group-Y) on yellow (group-Y). Among the reducing sugars in 'rainbow carrots', the amount of sucrose was two times higher than those of fructose and glucose. However, the content of glucose, fructose and sucrose as well as the total reducing sugars did not differ between color groups suggesting little variations on their tastes.

• Journal of the Korean Society of Tobacco Science
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• v.28 no.2
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• pp.75-82
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• 2006

This study was carried out to investigate the changes of free sugars, non-volatile organic and fatty acids in flue-cured leaf tobacco during aging. The threshed leaf tobacco(B1O and C1L) produced in 2002 crop year was aged for 21 month in warehouse of Oc-Cheon Leaf Tobacco Processing Factory. The leaf tobacco were sampled at three month intervals for analysis of free sugars, non-volatile organic and fatty acids. The major free sugars of flue-cured were glucose and fructose regardless of tobacco grades. After aging period of 21 months, the contents of glucose and fructose showed a tendency to slightly decrease, and there was no appreciable change in the contents of sucrose in B1O and C1L grades. The major compound of non-volatile organic acid and fatty acid were malic, oxalic and citric, linolenic, linoleic and palmitic acid regardless of tobacco grade. After aging period of 21 months, the contents of malic, malonic, oxalic and fumaric acid showed a tendency to slightly decrease, whereas succinic acid was slightly increased, and maleic acid was not changed in B1O and C1L grades. The decreases in fatty acid contents in B1O and C1L grade tobacco loaves after 21 month aging were 16.5% and 9.8%, respectively. The decreases in linolenic acid contents in two grades were the highest, showing 22.1% and 12.0% reduction after 21 month aging.

• The Korean Journal of Food And Nutrition
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• v.31 no.4
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• pp.559-564
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• 2018

Rehmannia glutinosa root (R. root) has been used as an traditional medicine, and is important resource for natural medicines and functional foods. However, R. root contains catalpol which is bitter, and undigested sugars, including stachyose and raffinose, which can cause diarrhea. Therefore, this study was performed to identify the changes in reducing sugar from undigested sugars and in catalpol contents in R. root slurry induced by aging treatments. R. root slurry was treated at $10{\sim}70^{\circ}C$ for up to 72 hr; and extracted with a 50% ethanol solution. The catalpol content was analyzed using HPLC-UVD. Reducing sugar content generated from undigested sugars was measured by the Nelson-Somogyi methods, and the reaction rates were calculated from their variation according to aging time and temperature. During the aging treatment, reducing sugar increased and catalpol decreased. Their formation and degradation rates were highest at $50^{\circ}C$ and $30{\sim}40^{\circ}C$, and their rates were $2.05mg/g{\cdot}hr$ and 23.09 to 23.33%/hr, respectively. These results indicated that aging treatment can positively affect the sweetness and digestibility of R. root slurry. Therefore, an aging treatment could be considered for improving the taste and digestibility of R. root.

• Korean Journal of Food Science and Technology
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• v.41 no.3
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• pp.345-349
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• 2009

This study measured the amounts of uronic acid, total sugars, non-cellulosic neutral sugars, phenolic compounds as well as antioxidants activity in cell wall materials (CWM) derived from different parts of deodeok (Codonopsis lanceolata). The values of the uronic acid (UA): neutral sugars (NS) ratio in polymers extracted from the CWM of the flesh and skin were 4 and 6, respectively. The total sugar contents of the flesh and skin were 788.6 and 824.9 ${mu}g/mg$ of CWM, respectively. Galactose and arabinose were the main noncellulosic neutral sugars. The chemical structure of five phenolic compounds from the CWM were analyzed and identified as vanillic acid, p-OH-benzaldehyde, vanillin, ferulic acid, and 8-O-4' diferulic acid by HPLC spectral data. Among them, p-OH-benzaldehyde, vanillin, and 8-O-4' diferulic acid were the first compounds identified from the deodeok. The content of 8-O-4' diferulic acid in the skin CWM was 56.1 ${mu}g/g$ AIR (alcohol insoluble residue). The ethanol-NaOH fractions from CWM had the highest oxygen radical absorbance capacity (ORAC) activities, followed by the AIR fractions and ethanol fractions.

• Molecules and Cells
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• v.40 no.10
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• pp.731-736
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• 2017

Taste sensitivity to sugars plays an essential role in the initiation of feeding behavior. In Drosophila melanogaster, recent studies have identified several gustatory receptor (Gr) genes required for sensing sweet compounds. However, it is as yet undetermined how these GRs function as taste receptors tuned to a wide range of sugars. Among sugars, fructose has been suggested to be detected by a distinct receptor from other sugars. While GR43A has been reported to sense fructose in the brain, it is not expressed in labellar gustatory receptor neurons that show taste response to fructose. In contrast, the Gr64a-Gr64f gene cluster was recently shown to be associated with fructose sensitivity. Here we sought to decipher the genes required for fructose response among Gr64a-Gr64f genes. Unexpectedly, the qPCR analyses for these genes show that labellar expression levels of Gr64d and Gr64e are higher in fructose low-sensitivity flies than in high-sensitivity flies. Moreover, gustatory nerve responses to fructose in labellar sensilla are higher in Gr64d and Gr64f mutant lines than in mutant flies of the other Gr64a-Gr64f genes. These data suggest the possibility that deletion of GR64D or GR64F may indirectly induce enhanced fructose sensitivity in the labellum. Finally, we conclude that response to fructose cannot be explained by a single one of the Gr64a-Gr64f genes.

• Korean Journal of Food Science and Technology
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• v.20 no.4
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• pp.459-462
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• 1988

Compositions of free-sugars and sugar-alcohols in three cultivated mushrooms, Pleurotus ostreatus, Lentinus edodes and Agaricus bisporus were analyzed by gas-liquid chromatography and compositional differences of these components depending on species, sizes of fruiting body and portions(pileus and stipe) were investigated. Glucose, fructose, trehalose, glycerol, arabitol and mannitol were identified in each of the three mushrooms. The major components were mannitol and arabitol in Lentinus edodes, mannitol in Agaricus bisporus, trehalose and mannitol in Pleurotus ostreatus. The total free-sugars and sugar-alcohols content were in the range of 12.7-18.9% in Lentinus edodes, 9.2-16.1% in Agaricus bisporus and 8.2-10.6% in Pleurotus ostreatus. Total contents of these components in Pleurotus ostreatus and Agaricus bisporus were higher in pileus than those in stipe and it was decreased as pileus size development in all of three edible mushrooms.

• Journal of the Korean Society of Food Science and Nutrition
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• v.13 no.1
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• pp.64-70
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• 1984

In this experiment, the changes in the components of carbohydrate and their enzyme activities were investigated to study the conversion of sugars in tomato under sub-atmospheric pressure storage .The results obtained are as follows: The soluble sugars in tomato fruits were, for the most part, fructose and glucose together with small quantity of sucrose and maltose. The content of fructose increased throughout the storage, while that of glucose increased at an early stage but decreased at the latter part, and that of sucrose decreased drastically with progress of storage. The activity of ${\alpha}-amylase$ and invertase playing important roles in conversion of sugars showed a rapid increase at onset of respiration climacteric, resulting that the content of total soluble sugar showed a tendency to decrease strikingly, whereas those of starch and sucrose to decrease rapidly. Thus, the effect of temperature was more pronounced than that of pressure.

• Journal of the East Asian Society of Dietary Life
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• v.14 no.6
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• pp.598-607
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• 2004

This study was conducted to examine the sensory characteristics and the contents of proximate composition and the free sugars of the Demi-glace with varying quantity of Omija extracts added. First, the qualities of Demi-glace sauces with varying quantity of Omija extracts added are as follows: (1) Proximate composition: The moisture content was 66.10～73.50%, and crude ash content was 1.59～1.89%. As the Omija extracts added increased, moisture content increased, whereas crude ash content decreased. The crude protein content was 6.12～7.95%. Among them, the one with the 2% Omija added showed the highest level of the crude protein. (2) Free sugars contents: In terms of total sugar contents, the control showed 1.32% and Omija sauces showed 1.44～1.55%. Major free sugars analyzed in the order of fructose, oligosaccharide, glucose and sucrose. Second, the results of sensory evaluation of Demi-glace sauces with the different levels of Omija added are as follows: (1) The preference of Demi-glace sauces according to occupation: Students and Cooks liked the one with the 2% Omija added in terms of color, flavor, taste, texture and overall acceptability. Cooks showed higher preference than students. (2) The preference of 5 tastes: It was found that Demi-glace sauce with the 2% Omija added was the best. The one with the 2% Omija added was suitable in terms of sweet taste and bitter taste and the one with the 3% Omija added was desirable for hot taste and saline taste. In terms of sour taste, the one with 1% Omija added was regarded as the most desirable one. (3) The preference for authentic tastes for Demi-glace sauce: In terms of simple taste, females showed higher preference than males. Demi-glace sauce with the 2% Omija added was found to be the best for savory taste, flavor enhancer taste, simple taste, after taste and overall acceptability. The one with the 1 % Omija added was regarded as the best for soft taste.