• The Korean Journal of Food And Nutrition
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• 제5권2호
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• pp.69-76
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• 1992

Sogokju, an old Korean rice wine, was brewed in laboratory scale in February, 1978, and the changes in chemical component and microorganisms in wine mash were investigated during brewing. In the course of first-mash brewing, lactic acid bacteria became the most predominant microflora in 3 days of fermentation lowering the pH of mash to 4.2. But at 7 days, the most predominant microorganism was changed from lactic acid bacteria to least, pH reached 3.6, and the saccharogenic activity of mash was reduced from initial 10 to 3.6. During second-mash brewing, remarkable changes did not occurred in pH and acidity, maintaining 3.5∼3.7 of pH and 8.0∼8.8 of acidity. Ethanol fermentation was proceeded vigorously until 20 days of fermentation, but it reached stationary state with 18.5% ethanol after 40 days, leaving reducing sugar unfermented in mash. Even if saccharogenic activity continued all during fermentation, it was thought to be too weak. The final product of Sogokju filterate, fermented for 60 day, contained 18.8% ethanol, 5.0% reducing sugar,0.4:1 total acid, 0.057% volatile acid, 0.206% amino acid and 7.3% extract. In sensory test, Sogokju scored good marks with similar level to commercial Bupju or Chungju. It had pale yellow color, gentle Nuluk-flavor and acid taste just a little strong.

• Journal of Mushroom
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• 제10권4호
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• pp.216-223
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• 2012

Oyster mushroom is one of the popular mushrooms for Korean people and it is thus one of the mushrooms that were mostly cultivated in Korea in addition to winter and king oyster mushrooms. To promote the consumption in terms of its nutritional value and determine the absorption mechanism in its physiological and metabolic aspects, we investigated the sugar composition of its fruit bodies according to the amount of sugar component in the medium. As a result from the treatment of 4 different sugar components to the sawdust medium of oyster mushroom varieties (i.g., Suhan 1 ho, Yeorum, Chunchu 2 ho), we detected fructose, glucose, ribose, xylose as a monosaccharide with ${\alpha}$-lactose and trehalose as a disaccharide. The sugar alcohols were also detected including glycerol, mannitol, myo-inositol, and sorbitol. The sugar components that were detected in all treatments were trehalose, mannitol, ${\alpha}$-lactose, fructose, glucose, ribose, and myo-inositol and the rest of the components were found in some treatments with their different quantity included in the fruit bodies. The amount of monosaccharides included in fruit bodies is comparatively low and Suhan 1 ho contained them more than other varieties. There was no remarkable difference in the amount of sugar components in fruit bodies depending on treated sugars and their amounts in the treatment. With the increase of lactose treatment, the sugar components were markedly increased and the amount of trehalose in the fruit bodies was different according to the varieties. Therefore, it is not possible to detect the trend of sugar components according to the medium used in the cultivation. The sugar alcohols in the fruit bodies were comparatively contained more in Suhan 1 ho and Chunchu 1 ho. The amount of mannitol in the fruit bodies was not possible to be detected in terms of its trend according to the treatment. For myo-inositol, its quantity is gradually increasing in Suhan 1 ho and Chunchu 1 ho and it is not possible to detent the trend in Yeorum. In conclusion, we only detected ${\alpha}$-lactose as a sugar component that showed a correlation between the amount of treatment and the amount of the fruit bodies. Therefore, the sugar components detected in the fruit bodies were transformed rather than direct absorption into fruit bodies and further studies are needed to address this question.

• Korean Journal of Food Science and Technology
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• 제14권4호
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• pp.315-323
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• 1982

The measurement of cell constant in a diaphragm-cell method is the most important factor. In order to get the correct cell constant, the diffusion coefficients of potassium chloride were measured, at various concentration and temperature of potassium chloride solution, and at the stirring rate in the cell. The pseudo-binary diffusion coefficients of organic aroma component (benzaldehyde) in sugar solution has been measured at various concentration and temperature with the cell constant obtained above. Experimental results were compared and discussed with the semi-empirical epuations from literatures. And, especially, the diffusion coefficient of benzaldehyde, $D_{ba}$ for a small solute diffusing in a viscous solvent of larger molecules is proportional to the -0.82 power of the viscosity of aqueous sugar solution, ${\mu}$ at constant temperature, $D_{ba}{\mu}^{0.82}=constant$.

• Journal of the Korean Society of Food Culture
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• 제10권5호
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• pp.443-448
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• 1995

Korean fresh elephant-foot (Amorphophalus konjak K. Koch) and its powder were analyzed and compared with foreign samples to investigate the physico-chemical characteristics of Korean konjak. The Korean fresh konjak contained 80.6% of moisture content and most of the solid component comprises much of sugar, protein and trace of fat and fibre. The mannan content of Korean konjak powder is far smaller than those of Japanese and Chinese konjak powder. The analysis of the Korean konjak revealed that glutamic acid, aspartic acid and arginine included 45% of total amount, and other amino acid was incresaed with the order of valine, serine, leucine and glycine. The Korean konjak contained a moderate amount of K component and other inorganic component was larger with the order of P, Na and Ca. The yield of refined powder obtained from dried chip of Konjak was 61.0% in Korean one and 57.5% in Chinese one. The degree of lightness of Chinese konjak powder was slightly higher than that of Korean product, but the difference could not be recognized by naked eye.

• Korean Journal of Microbiology
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• 제6권4호
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• pp.113-121
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• 1968

This study has been aimed to determine the ecological factors with relationship to the Jongkok production in view of fermentation technology by means of some strains, Asp. kawachii, which is now preserved by the author and the following factors are included during the study; inorganic salts, nitrogen, sugar, water contents and temperature. The results, are as follows: (a) Sugar among other above-mentioned factors is increasingly affecting the number of the short type of conidiophore on culture medium and the conidiophore is increased by direct ratio until glucose concentration of 50%, at which concentration is mostly effective for the short type of conidiophore, while other factors did not affect on it. (b) Until glucose concentration of 50% sugar component of culture medium is favorable for the spore formation of Asp. kawachii by direct ratio. And peptone or asparagine on nitrogen medium, calcium-phosphate among other inorganic salts, wheat bran and rice branare also favorable, but other factors rientioned earlier show no relationship with the spore formation. Sugar, however, also related with the spore color clearness of crimson and light brown, and spore color is mostly clear at the point of glucose concentration until 50%. And asparagine on nitrogen medium, calcium phosphate among other inorganic salts, rice bran did all affect on the color clearness, while other factors did not concern with color clearness. (c) Water, sugar and temperature have related with the acid formation which is promoted, by direct ratio at the point of water-saturated condition and glucose concentration of 50%, while temperature at $25^{\circ}C$favorably affected on the acid formation which is increased by inverse ratio at the temperature$25^{\circ}C$ to $45^{\circ}C$ And pH did not relate with the acid formation. (d) Cylindrical plate method devised by the author is mostly favorable for the preservation and isolation of culture, compared with the traditional slant medium method.

• The Korean Journal of Food And Nutrition
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• 제32권4호
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• pp.321-327
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• 2019

The objective of this study was to analyze the free sugar contents of ten kinds of fruits and fruit vegetables that were collected from many district in Korea. The analyzed results will be used as basic nutrition component reference to processing. The results were summarized as follows. The total free sugar contents among the ten kinds of fruit vegetables was highest in grape. The contents of glucose, fructose and sucrose were 6.39%, 6.27%, 0.28%, respectively. The average total sugar contents of four cultivar of apple was 11.42% and average fructose contents was 6.13%. The free sugar contents of thirteen samples of the same cultivar of apple were all differing with statistical significance. The average total free sugar contents of eight cultivar of peach was 8.66%. In case of tomato, glucose content was approximately 1.35~2.83% and fructose was 1.26~2.51%. The contents of glucose, fructose and sucrose in paprika were 2.19%, 2.06%, 0.1%, respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• 제37권1호
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• pp.48-52
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• 2008

The manufacturing characteristics and physicochemical component analysis of Bokbunja jam made with different additions of materials (Bokbunja, Bokbunja extract, sugar, and pectin) were investigated. There were no changes in the pH, total acidity, and sugar content of all Bokbunja jams that were prepared with different amounts of materials. L-value of color in the jam from the Bokbunja extract was the highest. a-value increased, but b-value decreased with the addition of pectin in jam. Spreadmeter value decreased while hardness increased in the jam added by pectin. The highest overall acceptability values in the sensory test for color, sweetness, adhesiveness, and overall favorite were 4.07, 5.33, 4.33, and 6.00, respectively, with the addition of 0.5% pectin.

• Journal of the Korean Society of Food Culture
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• 제3권4호
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• pp.385-390
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• 1988

This study was conducted to determine the interconversion of sugars in persimmon during the drying process and the textural properties of raw and dried persimmons using the changes of some chemical constituents, the analysis of sugar component, and the measurement of texture. Five varieties of persimmons were used in this experimment. As the drying proceeded, content of acetaldehyde and alcohol increased while soluble tannin content rapidly decreased. The rapid changes of these component obserbed in kyongsan Bansi and Hiratanenashi. Soluble sugars detected in raw persimmons were mainly glucose, fructose and sucrose. The content of sucrose was rapidly decreased in early stage of drying, while glucose and fructose were rapidly increased. The nearly same amount of glucose and fructose presented in the dried persimmon although there were some differences among varieties tested. The major component of white powder developed on the surface of dried persimmon was almost glucose. The texture profile analysis of the raw and dried persimmons was made with texturemeter and the quality of the dried persimmons was sensory evaluation method. Hiratanenashi and Sagoksi were determined as the suitable varieties in the processing of dried persimmons, but the varieties of Changdungyee and Namyang Susi were not suitable.

• KOREAN JOURNAL OF CROP SCIENCE
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• 제43권2호
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• pp.95-100
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• 1998

Seedling establishment of soybean [Glycine mar (L.) Mer-rill] is an important factor for soybean production in the field. The objective of this study was to determine the distribution of chemical composition in the emerging organs during seedling development in soybeans. Three soybean cultivars (Hill, Paldalkong, and Jangyeobkong) were planted at the Research Farm of College of Natural Resources, Korea University, on May 26, June 5, and June 14. Protein, oil, sugar, and starch contents were measured in each organ at each developing stage. Mean dry weight of three soybean cultivars decreased until VE stage and increased after this stage. Protein content of whole seedling did not change significantly during the seedling growth stage, but the amount in cotyledons markedly decreased with each growth stage increment. About 88% of the cotyledon protein was translocated to the other parts of the seedling at the V2 stage. Oil content of cotyledons sharply decreased until the V1 stage. Sugar content of the seedling was not detected at VE stage and starch content of seedlings increased slightly at VE and VC stages. For the changes of each metabolic component, the amount for whole plants decreased until the V1 stage and started to increase after this stage. The results of this study provide evidence for the breakdown of carbohydrates and oil at the initial stage of seedling growth.

• International Journal of Ocean System Engineering
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• 제1권1호
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• pp.32-36
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• 2011

EG/AD/S type model ice was originally selected as the primary model ice material for the MOERI ice tank in Korea. The existence of a sugar component in the EG/AD/S mixture may cause a serious maintenance problem. In order to understand the influence of sugar in the original model ice, a series of tests with EG/AD/S and EG/AD model ices were performed, and their material properties compared. Because the target strength of model ice in the full-scale MOERI ice tank is expensive and difficult to control, tests were performed under cold room conditions using a miniature ice tank. This paper describes the material properties of EG/AD/S and EG/AD model ices, such as flexural strength, compressive strength and elastic modulus. In order to obtain the desired strength and stiffness levels for the model ice, a warm-up process was introduced.