• Food Science and Biotechnology
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• v.18 no.6
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• pp.1398-1403
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• 2009

Present study deals with variations of physicochemicals including $\gamma$-aminobutyric acid (GABA), $\gamma$-oryzanol, free sugar, lipoxygenase activity, fat acidity, and germination rate from Korean brown rice cultivars. With increase of storage time and temperature, GABA, $\gamma$-oryzanol, lipoxygenase activity, and fat acidity increased, whereas free sugar and germination rate was reduced. Among cultivars, 'Gopumbyeo' exhibited the highest contents in GABA and $\gamma$-oryzanol during 12 weeks storage at $25^{\circ}C$ (GABA: $28.6{\pm}5.6{\rightarrow}170.4{\pm}4.6\;mg/100\;g$, $\gamma$-oryzanol: $6.1{\pm}0.7{\rightarrow}6.7{\pm}0.4\;mg/g$) and 'Ilpumbyeo' significantly decreased in free sugar during 12 weeks storage at $10^{\circ}C$ ($1,423.7{\rightarrow}1,058.4\;mg/100\;g$). Moreover, 'Taebongbyeo' exhibited the highest quality owing to low lipoxygenase activity, low fat acidity, and high germination rate. In free sugar compositions, sucrose exhibited the highest content (>70%), followed by fructose (>7%), raffinose (>5%), glucose (>3%), and maltose (>2%) during storage. Based on our results, changes of physicochemicals in stored brown rice may be important information in processing food and functional properties.

• Food Science and Preservation
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• v.3 no.1
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• pp.83-92
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• 1996

This study was conducted to estimate the shelf-life of 'Fuji' apples (Malus domestica Borkh) after CA storage. Apples stored In 1%O2+3%CO2, 2%O2+3%CO2 and 3%O2+3%CO2 at 2$^{\circ}C$ and 4$^{\circ}C$ for 8 months were stored in air at 10$^{\circ}C$, 80-85% RH for 16days. As a result of objective analysis, apples stored at 2$^{\circ}C$ wert mort effective in retarding the loss of weight flesh firmness, titratable acidity and peel color than those stored at 4$^{\circ}C$, but not the loss of soluble solid. Among storage atmospheres, 1%O2+3%CO2 at 2$^{\circ}C$ was more effective in retarding the loss of flesh firmness and green color than other atmospheres. Shelf-life of apples kept at 2$^{\circ}C$ estimated above 16 days. The contents of acetaldehyde and ethanol were not observed tn make large difference between storage conditions, but ethanol content of apples stored in 3%O2+3%CO2 at 4$^{\circ}C$ was Increased slightly for 16 days. According to sensory evaluations, apples stored at 2$^{\circ}C$ were significantly harder, juicier and more acid than chose stored at 4$^{\circ}C$. Particularly, high scores of apples stored in 1% and 2%O2+3%CO2 at 2$^{\circ}C$ Persisted for 16 days. Juiciness, hardness acidity and sweetness were related to the flesh firmness and titratable acidity. Overall acceptability was closely related to juiciness and hardness.

• Journal of the East Asian Society of Dietary Life
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• v.22 no.6
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• pp.886-894
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• 2012

For the development of Moru wine with enhanced sensory qualities, Moru (Vitis amurensis) wines were fermented with pine needles from Pinus densiflora Siebold et Zuccarini to make Moru-pine wine or medicinal herbs from Astragali Radix and Viscum album to make Moru-herb wine. Moru without pine needles or medicinal herbs was included as a control. Pine needles and Astragali Radix/Viscum album delayed the fermentation of Moru wine, but after 40 days of fermentation and aging, final ethanol contents, pH, acidity, and the sugar/organic acid content in these kinds of Moru wines had no differences. The final ethanol level and acidity of Moru wines were 11.5~12.9% and 1.1~1.2%, respectively, but any sugars (glucose, fructose and sucrose) were not detected in all Moru wines. These results are consistent with the general characteristics of Moru wines, which have a high acidity and low sugar contents. Relatively low browness and antocyanins were detected in Moru-herb wine decreasing its chromaticity in a sensory test. Overall, the supplements of Astragali Radix/Viscum album reduced the color of normal Moru wine, which might be applied toward the development of conventional Moru wines.

• Journal of the East Asian Society of Dietary Life
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• v.26 no.6
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• pp.543-549
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• 2016

The objective of this study was to investigate quality properties of 'Cheonghyang' wine using different commercial yeast strains. Soluble solid content, pH level and total acidity of 'Cheonghyang' grape were $20^{\circ}Bx$, pH 3.5 and 0.66%, respectively. Total acidity ranged from 0.91~1.06% in the middle stage of fermentation and decreased to 0.77~0.82% when alcoholic fermentation finished. Alcohol content in wines ranged from 12.5% to 12.9% showing no significant difference in yeast strains. Wine fermented with Red Fruit had high volatile acid content (189.0 mg/L) whereas wine fermented with Fermivin indicated low volatile acid content (77.7 mg/L). Wines made with Montrachet, Fermivin and Aroma White had low brightness (L-value) compared to others. Results from sensory evaluation demonstrated that commercial wine yeasts, Montrachet and Fermivin, can be applied to improve sensory properties of 'Cheonghyang' wine such as aroma, acidity and transperency. On the other hand, preferences of wine fermented with EC-1118 strain containing lots of tannins and total polyphenols were significantly reduced.

• Food Science and Preservation
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• v.23 no.7
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• pp.967-976
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• 2016

The objective of the present study was to investigate differences in quality of kimchi products produced in Korea, Japan, and China. Kimchi products from kimchi-producing countries with high consumer consumption such as Japan and China along with local products from Korea, where exporting has not yet started, were collected. Product pH, acidity, salinity, package pressure, gas production were assessed, and microbiological analyses and sensory evaluations were performed on kimchi products that were stored at either $4^{\circ}C$ for 63 d or $15^{\circ}C$ for 20 d. The pH and acidity results showed that as Japanese and Chinese kimchi had higher pH and lower acidity than that of Korean kimchi, which was determined to be indicative of insufficient microbial fermentation following kimchi production. Japanese kimchi had different microbial properties than those of Korean kimchi, which is due to differences in their manufacturing processes. Overall preferences derived from sensory evaluations were: Korean kimchi>Chinese kimchi>Japanese kimchi. The results of this study demonstrate the sensory superiority of Korean kimchi and may be useful when predicting consumers' acceptance level of Korean kimchi exported to other countries.

• Korean Journal of Food Science and Technology
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• v.36 no.2
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• pp.365-367
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• 2004

Electrolyzed-acid water was used to prolong shelf life of salted Chinese cabbage during storage, Chinese cabbage was salted, washed twice with electrolyzed-acid water, packaged in high-density polyethylene film, and stored at $10^{\circ}C$. Titratable acidity, pH, color, and microbial loads of salted Chinese cabbage were measured. Treated sample showed lower pH, total microbial count, and lactic acid bacteria than those of control, whereas almost equal titratable acidity and color, Acidity of treated sample maintained lower pH value until 6 days, and remained constant thereafter, Sharp decrease in L value occured after 2 days for control, and was delayed 4-6 days for treated sample. Salted Chinese cabbage treated with electrolyzed-acid water showed lower total microbial load ($10^3\;CFU/mL$) and lactic acid bacteria ($10^1\;CFU/mL$) after washing, whereas similar loads, compared to control after 6 days. Treatment with electrolyzed-acid water maintained higher quality for salted Chinese cabbage, with limited shelf life extension.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2004.11a
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• pp.80-81
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• 2004

The results obtained are summarized as follows; (1) Boehmite produced in the high temperature and acid region showed a nano fibrous shape with several nm in diameter and several hundreds nm in length having high specific surface areas with a maximum value of $409m^2/g$. (2) In order to obtain nano fibrous boehmite with high surface areas from nano metal powder, the hydrolysis reaction should be done at a high temperature over $50^{\circ}C$, high acidity under pH 6, and terminated before a transition to the bayerite phase.

• Bulletin of the Korean Chemical Society
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• v.27 no.6
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• pp.821-829
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• 2006

A series of catalysts, $NiO/La_2O_3-ZrO_2/WO_3$, for acid catalysis was prepared by the precipitation and impregnation methods. For the $NiO/La_2O_3-ZrO_2/WO_3$ samples, no diffraction lines of nickel oxide were observed, indicating good dispersion of nickel oxide on the catalyst surface. The catalyst was amorphous to X-ray diffraction up to 300 ${^{\circ}C}$ of calcination temperature, but the tetragonal phase of $ZrO_2$ and monoclinic phase of $WO_3$ by the calcination temperatures from 400 ${^{\circ}C}$ to 700 ${^{\circ}C}$ were observed. The role of $La_2O_3$ in the catalyst was to form a thermally stable solid solution with zirconia and consequently to give high surface area and acidity. The high acid strength and high acidity were responsible for the W=O bond nature of complex formed by the modification of $ZrO_2$ with $WO_3$. For 2-propanol dehydration the catalyst calcined at 400 ${^{\circ}C}$ exhibited the highest catalytic activity, while for cumene dealkylation the catalyst calcined at 600 ${^{\circ}C}$ showed the highest catalytic activity. 25-$NiO/5-La_2O_3-ZrO_2/15-WO_3$ exhibited maximum catalytic activities for two reactions due to the effects of $WO_3$ modifying and $La_2O_3$ doping.

• Culinary science and hospitality research
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• v.11 no.2
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• pp.91-109
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• 2005

The purpose of this study was to investigate the changes of vitamin C and lactic acid bacteria count in Dongchimi used different kinds of water (distilled water, purified water, Cho Jung Carbonated Natural water). Dongchimi used different kinds of water was fermented at $10^{\circ}C$ for 46 days. The changes of pH on Dongchimi used different kinds of water decreased in all samples during fermentation period, and then showed a slow decrease after 12 days of fermentation. The total acidity of Dongchimi used Cho Jung Carbonated Natural water arrived slowly at best tasting condition(0.3~0.4 point) compared with other conditions. The changes of salt content were ranked high one by one , Cho Jung Carbonated Natural water>purified water>distilled water during fermentation period. At early stage of fermentation, the changes of turbidity of Dongchimi used Cho Jung Carbonated Natural water showed highly as compared with other test conditions for 12 days of fermentation. Vitamin C content was measured high in Dongchimi used Cho Jung Carbonated Natural water during the fermentation period. Because calcium content was high in carbonated natural water, carbonated natural water had the highest calcium content during the fermentation period. The changes of lactic acid bacteria count showed the highest price at all experimental groups in 15 days of fermentation, but those of Dongchimi used Cho Jung Carbonated Natural water showed the highest price in 19 days of fermentation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.15 no.1
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• pp.39-44
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• 1986

Kacdugi fermented in the subatomospheric pressure(350mmHg) and polyethylene film package to improve the quality and to investigate the effect of fermentative control at $25^{\circ}C$. Brix degree, acidity, vitamin C content and number of total microbe and Lactobacilli was determined and also, the edible period of kacdugi was checked up by sensory assessment. The increasing rate of brix degree during kacdugi fermentation was high in the subatomospheric pressure, but decreased at the last period of fermentation as same tendency to the control, and it was preferably increased at the last period of fermentation in the polyethylene film package. However, the acidity was higher in the control than sbuatomospheric pressure but it was low in the polyethylene film package. Vitamin C content was high in the control at beginning and middle period of fermentation but high in sbuatomospheric pressure, and was low in the polyethylene film package at the last period of fermentation. The number of Lactobacilli was more in the subatomospheric pressure and polyethylene film package than the control, but it was suddenly incressed for the total microbe in the polyethylene film package at last period of fermentation. The edible periods of kacdugi by the sensory assessment of sour flavor, hardness and complex flavor was second days in the control. third days in the polyethylene film package, and fifth days in the subatomospheric pressure after soaking.