• Korean journal of food and cookery science
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• v.26 no.5
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• pp.655-664
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• 2010

This work aimed to investigate the physiochemical properties of commercial sugars (white sugar, dark brown sugar, organic sugar, and muscovado) and sugar beet. Percentages of crude protein, crude fat and crude fiber in sugar beet were 4.06, 6.36 and 0.02%, respectively, and the degrees of sugar of white sugar and sugar beet were $93^{\circ}$ Brix and $78^{\circ}$ Brix, respectively. L(lightness) value scores of white sugar were higher while the turbidity of sugar beet was higher. White sugar, dark brown sugar, and organic sugar were composed of only sucrose, whereas muscovad and sugar beet were composed of fructose, glucose, and sucrose. The highest organic acid content was observed in sugar beet. The contents of amino acids in sugar beet were in the following order: proline ($161.23\;{\mu}g$/100 g) > aspartic acid ($161.23\;{\mu}g$/100 g) > leucine ($36.93\;{\mu}g$/100 g) > alanine ($17.40\;{\mu}g$/100 g). There were 16 free amino acids in sugar beet. The highest mineral contest was observed in sugar beet in the order of K > Ca > Na > Mg. This result indicates that sugar beet can be prepared by considering the characteristics of natural sugar materials.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.8
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• pp.1353-1358
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• 2004

This study was conducted to increase crude protein and reducing sugar contents in pollen extracts by proteases. Four commercial neutral proteases (Alcalase 2.4L, Protamex, Flavozyme and Protease A) and two alkaline proteases (Protease S and Protease P) were used to prepare acorn and Darae pollen extracts. Contents of moisture, ash, crude protein and crude fat of acorn pollen were 5.2%, 2.7%, 6.2% and 22.3%, respectively, while those of Darae pollen were 5.4%, 2.8%, 1.8% and 27.8%, respectively. Contents of crude protein and reducing sugar in pollen extracts were increased by proteases. Alcalase 2.4L was the most effective in increasing protein contents while Protease A in increasing reducing sugar contents. It is suggested the use of proteases is one of the potential methods for increasing the contents of crude protein and reducing sugar in preparation of pollen extracts.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• v.2 no.1
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• pp.37-48
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• 1998

Effect of plant hormones on the leaf senescence of mung bean (Phaseolus radiatus) was investigated by measuring the changes of reducing sugar contents and invertase isozyme activities in detached leaves treated with NAA, $GA_3$ or BA. During dark-induced senescence, reducing sugar contents in the detached leaves increased temporarily at 4 d, thereafter decreased rapidly and reached minimum values within 7-14 d. The pattern of soluble acid invertase activity in the senescing leaves kept in the dark was similar to that of reducing sugar accumulation, whereas the activities of alkaline and extracellular invertases were not significantly changed during leaf senescence. Therefore, these results suggest that soluble acid invertase, but not alkaline and extracellular invertases, induces the accumulation of reducing sugar during leaf senescence of mung bean plants. Exogenous NAA application had little or no effect in the increase of soluble acid invertase activity during dark-induced senescence compared to the control. However, exogenous applications of $GA_3$ and BA led to the increase of soluble acid invertase activity in the senescing leaves. Particularly, BA application was very effective in enhancing the activity of soluble acid invertase as well as in delaying chlorophyll breakdown during dark-induced senescence. These results suggest, therefore, that BA regulates the activity of soluble acid invertase, which leads to the accumulation of reducing sugar, and the stability of photosynthetic apparatus to delay leaf senescence.

• Journal of Environmental Science International
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• v.2 no.1
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• pp.37-48
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• 1993

Effect of plant hormones on the leaf senescence of mung bean (Phseoln radiatus) was investigated by measuring the changes of reducing sugar contents and invertase isozyme activities in detached leaves treated with NAA, $GA_3$ or BA. During dark-induced senescence, reducing sugar contents in the detached leaves increased temporarily at 4 6, thereafter decreased rapidly and reached minimum values within 7-14 6. The pattern of soluble acid invertase activity in the senescing leaves kept in the dark was similar to that of reducing sugar accumulation, whereas the activities of alkaline and extracellular invertases were not significantly changed during leaf senescence. Therefore, these results suggest that soluble acid invertase, but not alkaline and extracellular invertases, induces the accumulation of reducing sugar during leaf senescence of Rung bean plants. Exogenous NAA application had little or no effect In the increase of soluble acid invertase activity during dark-induced senescence compared to the control. However, exogenous applications of $GA_3$ and BA led to the increase of soluble acid invertase activity in the senescing leaves. Particularly, BA application was very effective In enhancing the activity of soluble acid invertase as well as in delaying chlorophyll breakdown during dark-induced senescence. These results suggest, therefore, that BA regulates the activity of soluble acid invertase, which leads to the accumulation of reducing sugar, and the stability of photosynthetic apparatus to delay leaf senescence.

• Journal of the Korean Society of Food Culture
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• v.12 no.1
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• pp.53-61
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• 1997

This study was carried out in order to investigate general characteristics, sugars and organic acids contents of Korean traditional soy sauce, and to find out possibility of high quality soy sauce production in a short period through high concentration soy sauce making. In this study, we prepared three different types of soy sauce, low concentration soy sauce (Chungjang), high concentration soy sauce and Kyupjang, high quality traditional Korean soy sauce. pH of soy sauce were $4.46{\sim}4.90$ and did not show difference among three samples. Titratable acidity, buffering power and total free acid content were the highest value in Kyupjang. Kyupjang showed the highest contents of salt and pure extract. As the ripening period increased, the salt content increased in Chungjang samples, but decreased in Kyupjang. Reducing sugar contents of Kyupjang, high concentration soy sauce and low concentration soy sauce were 1.13%, 0.76% and 0.53%, respectively. Free sugar in soy sauce were analyzed maltose, glucose, galactose and fructose. Total free sugar content was highest in high concentration soy sauce, however, contents of glucose and fructose were higher in Kyupjang than in Chungjang samples. Galactose was the main free sugar in Chungjang, but glucose was in Kyupjang. Among identified volatile organic acid, acetic acid was present in the highest concentration, and volatile organic acid content was highest in the high concentration soy sauce at 150 days. 20 nonvolatile organic acids were detected in Korean traditional soy sauce. Succinic acid, lactic acid and 2,5-pyridine dicarboxylic acid were the main nonvolatile organic acid in soy sauce.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.4
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• pp.575-581
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• 2000

Quality characteristics of kochujang prepared with appleand persimmon were investigated during 14 weeks of fermentation. The water activity decreased slightly during fermentation and was higher in kochujang (I) prepared with apple than in kochujang (II) prepared with presimmon. The reducing sugar contents increased from 10.95% in kochujang (I) and 10.30% in kochujang (II) to 16.68, 19.14% after 10 weeks of fermentation, respectively. The free sugar contents in kochujang (I) were maltose 10.55, glucose 8.47 and fructose, 3.02% after 12 weeks of fermentation. The free sugar content in kochujang (II) were maltose 10.55, glucose 21.65, glucose 8.71 and fructose 2.98 after 6 weeks of fermentation. The major free sugar in kochujang (I) and (II) was maltose. The organic acids detected in kochujangs were citric, malic, lactic and oxalic acids. The contents of citric acid and malic acid were higher than other acids in both kochujangs. The contents of total free amino acids were 187.59~420.94 mg% in kochujang (I) and 154.67~316.93 mg% in kochujang (II). The contents of aspartic acid, proline and glutamic acid were high in kochujang (I) and (II).

• KOREAN JOURNAL OF CROP SCIENCE
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• v.27 no.1
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• pp.87-93
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• 1982

Dihaploid lines derived from the another of the $F_1$ of single cross, SC72 $\times$ Hicks (Nicotiana tabacum L.) were estimated the variation, heritablities, genetic correlations and path-co-efficients on agronomic characters and chemical compositions. Dinaploids exhibited reduced vigor and growth when comparecd with the mid-parent value but had increased nicotine contents, and the range of dihaploids characters were deviated more than that of their parents. Heritabilities of days to flowering, leaves per plant, nicotine. contents, leaf size and plant height appeared high value, and the yield, value per kg. and reducing sugar contents were low. There were positive genetic correlations between yield, and value per kg., leaf width, leaves per plant and reducing sugar contents and negative genetic correlations appeared between nicotine contents and the other characters except for index of leaf shape. Path-coefficient analysis of genotypic correlation coefficients showed that leaves per plant and leaf width lave a high direct effect, and plant height and days to flowering have a high indirect effect on yield, respectively.

• Food Science and Preservation
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• v.22 no.3
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• pp.314-321
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• 2015

This study was conducted to investigate the quality and characteristics of semi-dried persimmons soaked in different concentrations of sugar solution and stored at $7^{\circ}C$ for 20 days. The L value and chroma value were significantly higher in S5 and S10 compared to the other concentrations of sugar solution. The ${\Delta}E$ and browning degree were increased according to the increase in concentration of sugar solution. Total sugar, reducing sugar, and sugar free contents were higher in the control (semi-dried persimmon) than those in S0, but they increased according to the increase in concentration of sugar solution. Polyphenol oxidase and peroxidase activities were decreased according to the increase in sugar solution concentration, which were highest in S0 among other semi-dried persimmons soaked in sugar solutions. Total ascorbic acid content was highest in S10 (12.29 mg/g), followed by S0 (2.54 mg/g), S5 (7.76 mg/g), S15 (6.05 mg/g), and S20 (5.05 mg/g). Total polyphenols, flavonoids and proanthocyanidins contents were the highest in S10 compared to other semi-dried persimmons soaked in sugar solutions. Furthermore, the same tendency was observed with DPPH radical scavenging ability. These results showed that 10% sugar solution could be applied to semi-dried persimmons in order to achieve high quality, nutritional value, and browning inhibition.

• Journal of Life Science
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• v.11 no.1
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• pp.14-21
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• 2001

To investigate the changes of carbohydrate metabolism in the senescing leaves of Zea mays during dark-induced senescence, the changes in the contents of reducing sugar, sucrose and starch as well as the activities of sucrose synthase, three isozymes of invertase, and ${\alpha}$-amylase were measured. In the senescing leaves, the content of reducing sugars temporarily increased at 4 d and rapidly decreased thereafter, whereas sucrose contents gradually decreased thereafter, whereas sucrose contents gradually decreased until 3 d of senscence and significantly decreased thereafter. The activities of intracellular invertases such as soluble acid and alkaline formed gradually enhanced until 4 d of leaf senescence and significantly declined thereafter. The extracellular invertase activity showed no significant changes during leaf senescence. The deactivation of sucrose synthase was observed within 3 d of leaf senscence. On the other hand, the starch contents gradually declined during 2 d of leaf senescence, and showed a temporary increase at 3 d, which is similar to the pattern of sucrose synthase activity., These results imply that sucrose in the senescing leaves. The major enzymes which correlated to the breakdown of sucrose during dark-induced senescence were soluble acid and alkaline invertases, not sucrose and ABA accelerated leaf senescence by inducing the accumulation of reducing sugar. These result, therefore, that leaf senescence may be mediated by the temporary quantitative changes of reducing sugar induced by the activation of intracellualr inveertases.

• Food Science and Preservation
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• v.3 no.1
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• pp.23-32
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• 1996

Total carotenoid contents, color values and spectrum characterization in the range of UV of fruit juice and organic acid and free sugar contents determined by HPLC were investigated on 10 varieties of Cheju citrus fruits. Carotenoid contents of juice were 0.47-9.20$\mu\textrm{g}$/ml which showed higher with Dangyooja while showed lowest content with Meiwa Kumquat. Lightness (L) of juice was highest in Meiwa Kumquat, and in the order of Sankyool, Navel orange and Hungjin. Redness(a) and yellowness(b) were in the order of Dangyooja, Natsudaidai, Sambokam and Kinkoji. The maximum absorption wavelengths if citrus Juices were variable at 269.5-285.5nm according to varieties and it was observed that were changed by mixing with Juices of other varieties. Major organic acids of citrus juice were citric and malic acid, and citric acid was 64.4-95.1% of total organic acids. Ascorbic acid was high in Navel orange, Sudachi and Dangyooja, and low in Meiwa Kumquat and Hungjin. Major free sugars were sucrose, glucose and fructose. Sucrose was 49.2-75.2% of total free sugars, and high in Sankyool and Meiwa Kumquat. Glucose and fructose were high in Meiwa Kumquat and Navel Orange.