• Korean Journal of Food Science and Technology
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• v.42 no.1
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• pp.56-62
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• 2010

Quality characteristics such as alcohol, acid, and sugar contents of takju brewing mashes prepared using several yeasts were investigated during 12-days of fermentation. Among the yeasts examined, S. cerevisiae led to the highest level of ethanol (10.2-13.4%) and total minor alcohols (0.729-0.831 mg/mL). Regardless of the yeasts used, the acidity showed drastic changes (pH from 3.4-4.2 down to 2.4-2.7) during the first 2 days, and displayed negligible changes from day 4. The total acid contents rapidly increased to the first 4 days of fermentation and leveled off from 4 to the end of fermentation period. The common organic acid components were lactic, succinic and acetic acids. The total and reducing sugar contents varied depending on the yeasts used, with mashes prepared using S. coreanus and S. rouxii producing the maximum total sugar contents (5.43-5.5%) at the end of fermentation. The reducing sugar showed its maximum (7.53-14.89%) at day 2, after which it decreased to its minimum levels (3.04-4.52%). The common free sugar components were glucose and fructose, while S. ellipsoideus led to a higher free sugar level (0.35-5.29%).

• Korean Journal of Fisheries and Aquatic Sciences
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• v.26 no.4
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• pp.340-345
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• 1993

In order to investigate the quality changes during the storage after curing were determined volatile basic nitrogen(VBN), amino nitrogen, total creatinine, total carotenoid, extents of browning, reducing sugar and glycogen. During the storage of $5{\pm}1^{\circ}C$ after fermented for 1 or 2 days at $25{\pm}1^{\circ}C$, amino nitrogen increased slowely. Whereas the total carotenoid and glycogen decreased. Browning did not occurred for 50 days. Total creatinine increased gradually until 20 days but reducing sugar increased continuously through 50 days of storage. The result of sensory evaluation during the storage of fermented ascidian added $0.1\%$ papain and protease-A with NaCl $10\%\;and\;15\%$ showed that original taste and flavor of ascidian for $30{\sim}40$ days of storage at $5{\pm}1^{\circ}C$.

• Korean Journal of Food Science and Technology
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• v.22 no.7
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• pp.828-832
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• 1990

Pileus and stipe extracts of shiitake mushroom were prepared with various ethanol concentration by different extraction time at $60^{\circ}C$. Yields, total reducing sugars, free amino acids and nucleotides in ultrafiltrated extracts were analyzed. Yields were higher in hot water extracts but there was no difference depending on changes of extraction time. Total reducing sugar contents got higher by hot water extraction than by solvent extraction. In hot water extracts of the pileus and stipe, reducing sugar content were in the range of $416.18{\sim}488.18\;mg%\;and\;435.37{\sim}452.12\;mg%$, respectively. Threonine+serine, glutamic acid, lysine and arginine were dominent in the free amino acids pool of raw material. The contents of free amino acids in hot water extracts of pileus and stipe were about 528.46mg% in 2 hr and 221.01 mg% in 3 hr. The proportion of bitter amino acids in extracts to total free amino acid contents was in the range of $16{\sim}29%,\;35{\sim}37%$ in pileus and stipe extracts, respectively. Nucleotides contents were higher in pileus than in the stipe. When the 25% ethanol solution was used for extraction solvent, nucleotides contents in pileus and stipe extracts was high.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.5
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• pp.775-783
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• 1997

Morphologically different 18 strains were isolated and examined for their abilities to inhibit ACE. Those strains were cultured in the medium containing 10% of soybean extract at 37$^{\circ}C$ for 48hr or fermented with boiled soybean at 3$0^{\circ}C$ for 60 days. The concentration of inhibitors to inhibit 50% of ACE activity, $IC_{50}$ was measured on the culture broth of each strain and also on the hot-water extract from 20, 40 and 60 day fermented Doenjang by each strain. As a result, SCB-3 which is isolated from Meju showed the highest ACE inhibitoryactivity on the cultured broth and 40 day matured Doenjang. Then, $IC_{50}$ of SCB-3 was 0.02 mg/ml and 0.26mg/ml respectively. SCB-3 was identified as a Bacillus subtilis based upon its morphological, biochemical and physiological properties. Changes in general components and ACE inhibitory activity of Doenjang fermented by SCB-3 were examined during 90 days. Total acidity of Doenjang was increased from 1.39% to 1.66% and pH was decreased from 6.02 to 5.79 after 90 days fermentation. Total sugar contents were decreased from 16.4% to 15.1% and reducing sugar contents was also decreased from 2.45% to 1.62%. Total nitrogen contents were nearly not changed, but amino nitrogen contents were drastically increased from 196mg% to 541mg%. The numbers of total microorganism were increased to 1.1$\times$$10^{8}$ cells/g after 45 days. Protease activity was increased to 622.1U/g after 75 days. The highest ACE inhibitory activity was shown in 60 day fermented Doenjang and $IC_{50}$ of the hot-water extract was 0.31mg/ml.

• Culinary science and hospitality research
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• v.21 no.6
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• pp.255-263
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• 2015

This study was conducted to test the fermenting of high quality vinegar using Wasabi japonica Matsum leaves. Alcohol fermentation with Wasabi japonica Matsum leaves resulted in the reduction of sugar and sugar alcohol content during fermentation, which decreased sharply over 3 days. The alcohol content was maximized (15.4%) after 8-days of alcohol fermentation at $27^{\circ}C$ by adjusting the initial sugar concentration to $27^{\circ}Brix$, and vinegar with an acidity of 5.1% was obtained after 21-days of acetic acid fermentation at $30^{\circ}C$. The pH was shown to be 3.5 after 21-days of acetic acid fermentation at $30^{\circ}C$. Regarding the color of Wasabi japonica Matsum leaves vinegar, the L and b values increased according to fermentation time, whereas a color values decreased. In conclusion, based on the above results, it is determined that the use of Wasabi japonica Matsum leaves allows for the production of high-quality vinegar.

• 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 Plant Resources
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• v.24 no.6
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• pp.688-695
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• 2011

The composition of free sugar, free amino acid, and fatty acid in tubers of the cultivars 'Superior', 'Sinnamjak', and 'Chubaek' were evaluated at the two sites with different altitude, Gangneung (20 m altitude) as lowland and Daekwallyeong (760 m altitude) as highland. The average reducing sugar content of the three potato cultivars harvested in Daekwallyeong and Gangneung was 1.1% and 2.3%, respectively, which showed two-fold difference between the two locations. Average total sugar content was also two-folds lower in potatoes harvested in Daekwallyeong (6.3%) than those harvested in Gangneung (12.2%). Average content of free amino acids of the three potato cultivars harvested in Daekwallyeong and Gangneung was 1,325 mg/100g and 1,051 mg/100g, respectively. The cultivar 'Chubaek' has the highest amino acid content among the three tested cultivars. Potatoes from Daekwallyeong have higher unsaturated fatty acid levels than those from Gangneung. During the tuber development, unsaturated fatty acids levels increased in tubers grown in Daekwallyeong, but decreased in those grown in Gangneung. These results indicate that the quality of potatoes from Daekwallyeong is from Gangneung for food processing purpose for human consumption.

• Journal of the Korean Society of Tobacco Science
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• v.4 no.2
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• pp.11-16
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• 1982

To investigate the effect of reciprocal grafting between Hyangchio (H) and L. A. Burley 21 (L.A), one a higher producer of nicotine and low yield, the other, a low producer of nicotine and high yield, growth of various parts of each variety and chemical constituents of these parts were evaluated. The results were as follows : The growth of H/H graft was depressed when compared to hyangchio and H/L. A. and L. A. Burley 21 showed most vigorous growth plants having L. A. Burley 21 top. The amount of total alkaloids were low in leaves and stems of plants having L. A. Burley 21 roots (L. A., L. A./L. A., H/L. A.). Plants having Hyangchio roots (H, L. A./H) were high in total alkaloids. The contents of reducing sugar were high in plant having Hyangchio top compared to L. A. Burley 21 tops, but there were not diffences in contents of ether extracts among all treatments.

• Journal of the Korean Society of Tobacco Science
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• v.21 no.2
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• pp.182-187
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• 1999

A bulk curing experiment was carried out to evaluate the effect of air flow reduction in the bulk barn from color fixing stage in the chemical properties of cured leaves, The air flow was controlled by reducing air velocity of a blower from 0.3m/sec to 0.2m/sec using a boltage regulator(Slidac). The bulk curing before color fixing stage was processed in the conventional curing method. Reduction of air circulation in bulk barn did not affected so much on change of the contents of the main chemical components in cured leaved, such as nicotine, total sugar, total nitrogen, petroleum ether extract, and organic acids. Only a slight increase in essential oil contents, such as solanone, damascenone, damascone, $\beta$-ionone, and megastigmatrienone isomer, could be observed in leaves cured in the reduced air flow.

• Journal of the Korean Society of Tobacco Science
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• v.11 no.2
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• pp.143-148
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• 1989

Field experiment was conducted to find out the chemical characteristics of 12 Korean local varities, Local varities were compared with oriental, flue-cured and burley tobacco. Among tested varities, Hyangcho and Matskawa were desirable in respect of flavor, leaf color and texture. Hyangcho and Matskawa were higher in the content of nicotine and petroleum ether extract. Gajacho, Byeolcho and Kukjuo were higher in the content of reducing sugar, but lower nicotine, total nitrogen and petroleum ether extract. The nicotine and total nitrogen content of Kwangcho, Daruma and Catterton were lower than that of Br. 21. In the content of volatile organic acid which were major characteristic component of oriental tobacco, the Korean local varities were lower in the content of 3-methyl butanoic and 3-methyl pentanoic acid, but hirities, Hyangcho, Matskawa and Daruma were higher in the content of volatile organic acid. Korean local varities, especially small leaf group, were higher in the content of benzyl alcohol and furfural than any other type tobacco.