• Korean Journal of Food Science and Technology
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• v.41 no.2
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• pp.162-166
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• 2009

In an effort to determine the effect of ingredients on the sensory characteristics of dongchimi, 10 different samples of dongchimi were prepared in various combinations of 4 ingredients most notably red pepper, garlic, ginger, and green onion and their physicochemical, microbiological, and sensory characteristics were assessed. Each ingredient utilized for the preparation of dongchimi did not affect changes in pH and titratable acidity, but exerted significant effects on sensory scores of overall acceptability, acid odor, salty, and hot taste. In cluster analysis using the 'Ward' method, dongchimi samples were classified into three groups. The first group was the samples prepared with a variety of ingredients including garlic, and the second group included samples prepared with the sole ingredient, except for red pepper. The third group had features similar to those of the sample prepared without other ingredients. It was determined that garlic played a crucial role in the sensory properties of dongchimi, and the addition of various ingredients enhanced hot taste and reduced acid odor, sourness, moldy odor, and carbonated taste by their interaction.

• Korean Journal of Food Science and Technology
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• v.30 no.4
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• pp.877-882
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• 1998

To establish optimum drying methods for Korean yam, freeze drying, cool air drying and hot air drying methods were compared by determining some quality criteria. The native color, odor, taste and viscosity of raw yam were preserved by only freeze drying at less than $40^{\circ}C$. The native white color of yam changed to brown and odor and taste of yam decreased largely by cool air drying and hot air drying. Especially cooked and roasted flavor was developed in hot air dried yam. The viscosity of cool and hot air dried yam was about half than that of freeze dried yam. Conclusively freeze drying method was shown optimum to preserve quality properties of yam such as viscosity, color, odor and taste. The physical properties of yam powder such as dispersiveness and solubility was the best in $40{\sim}60{\;}mesh$ particle size.

• Journal of Korean Society of Water and Wastewater
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• v.21 no.3
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• pp.341-348
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• 2007

The efficiency of powdered activated carbon (PAC) for removing taste and odor (T&O) in drinking water supplies is dependent on the contact time, quality of mixing, and the presence of competing compounds. All of these are strongly influenced by the stage in the treatment process at which the PAC is added. In conventional water treatment plants (WTPs), PAC is commonly added into the rapid mixing basin where chemicals such as coagulants, alkaline chemicals, and chlorine, are simultaneously applied. In order to prevent interference between PAC and other water treatment chemicals, alternative locations for addition of PAC, such as at transmission pipe in the water intake tower or into a separated PAC contactor, were investigated. Whatever the location, addition of PAC apart from other water treatment chemicals was more effective for geosmin removal than simultaneous addition. Among several combinations, the sequence 'chlorine-PAC-coagulant' produced the best result with respect to geosmin removal efficiency. Consequently, when PAC has to be applied to cope with T&O problems in conventional WTPs, it is very important to prevent interference with other water treatment chemicals, such as chlorine and coagulant. Adequate contact time should also be given for adsorption of the T&O compounds onto the PAC. To satisfy these conditions, installation of a separated PAC contactor would be the superior alternative if there is space available in the WTP. If necessary, PAC could be added at transmission pipe in the water intake tower and still provide some benefit for T&O treatment.

• Journal of Korean Society on Water Environment
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• v.27 no.1
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• pp.110-114
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• 2011

In this paper, in order to eliminate Limnoperna fortunei inhabiting the water conduction pipeline, prechlorination at the intake station was employed to improve the degradation of water quality due to the high pH of raw water taken at the downstream of Paldang Dam, algal growth, etc.. With the prechlorination concentration of 1.0mg/L at the intake station, the pH in the water well at the treatment plant decreased by 0.4, and with 1.5mg/L, by 0.6. Also, it eliminated Chlorophyll-a by about 95%, and the population of algae by about 49%. Such disinfection by-products (DBPs) as Trihalomathanes (THMs), Haloacetic Acids (HAAs), and Chloral Hydrate (CH) were under the quality standard for potable water, showing no change by the prechlorination, while raising the prechlorination rate from 1.0 up to 1.5mg/L, the DBPs in the water well increased by 1.5 to 3.1 times. As a consequence of testing Kyungan Stream, a branch stream flowing into Lake Paldang, the prechlorination (0.57mg/L, 1.14mg/L, 1.71mg/L) had no effect of eliminating the taste and odor compounds and total organic carbon (TOC) which is the DBPs precursor. As for the efficiency of Geosmin elimination by the rates of prechlorination and powder activated carbonation (PAC), it was found that the higher the concentration of PAC was (30ppm>20ppm>10ppm), the higher the efficiency was; the higher the rate of prechlorination was, the lower the efficiency by PAC was. Therefore, when taste and odor occur from raw water, suspending prechlorination at the intake or lowering the rate was proved to be more effective in eliminating the taste and odor compounds by PAC.

• Korean journal of food and cookery science
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• v.21 no.4 s.88
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• pp.536-544
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• 2005

In the results of sensory evaluation, beef steak was preferred with the highest overall acceptability while lamb steak was less preferred than pork in flavor and overall acceptability. Sensory tests were conducted to examine whether taste, aroma, or texture is the dominant contributor to people's ability to identify the animal species of meat. The meat samples used were beef, pork, and lamb. Panelists wearing eye masks ate cooked pieces, patties, and heated soups prepared from the meats of these 3 species with and without pinching their noses to regulate the aroma sensation. The results led us to the conclusion that aroma is the most important contributor to the identification of lamb meat, with texture being the 2nd most important contributor. The contribution of taste appeared much smaller than that of aroma and texture. A sensory evaluation of lamb steaks with added herbs or herbal vegetables showed that steak with ginger and rosemary was preferred as having the significantly highest overall acceptability. It was also more preferred au 3 kinds of steak with added garlic and mint, garlic and rosemary, and ginger and mint in appearance, taste and flavor, although there was no significant difference. In difference test, odor was least noticeable in lamb steak when ginger and rosemary were added. Its taste gained the highest preference level, although the difference was not significant. A sensory evaluation that measured the effect of herbs and herbal vegetables on lamb steaks showed that steak with ginger and rosemary had the significantly highest overall acceptability. The second most preferred was beef steak, which had most significantly preferred in taste, and which ranked lower than lamb in flavor with no significant differences. The difference test showed lamb steak with ginger and rosemary scored the least odor and the highest level of palatability.

• Journal of the Korean Society of Tobacco Science
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• v.29 no.2
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• pp.85-89
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• 2007

This study was conducted to evaluate the prediction of sensory characteristics of smoke from the leaf chemical compounds and characterize leaf chemical components for the best tobacco taste's leaves in oriental tobacco. For analytical and sensory evaluations, seventy two grades were used. Sensory evaluation of tobacco smoke for six attributes were scored on fifteen-point scale by $10{\sim}14$ expert panels trained to estimate smoking quality quantitatively. The major leaf chemical compounds to predict the sensory characteristics of smoke were ether extract for tobacco-like, nicotine for impact and total nitrogen/nicotine ratio for irritation, and total sugar for off taste & odor. Within ${\pm}20%$ range of difference, the predictable probabilities of sensory characteristics of smoke from the leaf chemical compounds were 87.5 % for off taste & odor and $94.4{\sim}98.6\;%$ for tobacco-like, impact and irritation. As a result of K-means cluster analysis on the basis of tobacco taste, the desirable leaf chemical compound contents were $5.9{\sim}8.3\;%$ in ether extract, $1.35{\sim}2.27\;%$ in nicotine and $1.17{\sim}2.24$ in total nitrogen/nicotine ratio. This study suggest that the some regression equations may be useful to predict the sensory characteristics of tobacco smoke with a few selected leaf chemical compounds in oriental tobacco and to select the oriental tobacco leaves by means of enhancing the tobacco taste of cigarette.

• Korean Journal of Food Science and Technology
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• v.32 no.1
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• pp.9-16
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• 2000

Aroma of various extracts of Agastache rugosa O. Kuntze was analyzed by electronic nose with 32 conducting polymer sensor arrays. The 57 extracts were prepared by extraction solvents (hot water, ethanol and NaCl solution), extraction temperatures $(100,\;80\;and\;60^{\circ}C)$, solvent mixture ratios of solvent (10 times 35 times) and parts of Agastache rugosa O. Kuntze(flower, leaf and stem). Aroma pattern of Agastache rugosa O. Kuntze extracts showed big difference in normalized pattern and odor intensity with extraction temperatures and parts, but showed no difference with extraction solvents. Especially in the case of ethanol extracts, because odor of ethanol itself was very strong, difference in aroma of extracts with extraction temperatures and parts did not show through the electronic nose. The organoleptic characteristics such as mint odor, grassy odor, mint taste, medicinal herb taste and sweetness for Agastache rugosa O. Kuntze extracts were determined by the profile test and the result of sensory evaluation by quantitative descriptive analysis was explained to QDA diagram. In correlation with the result of aroma analysis by electronic nose and the sensory evaluation, difference in aroma pattern among the extracts concretely brought to light definite characteristics such as mint odor and mint taste.

• Journal of Korean Society on Water Environment
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• v.27 no.1
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• pp.104-109
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• 2011

The removal efficiencies of 2-methylisoborneol (MIB) and geosmin were investigated to reveal removal characteristics of typical organic compounds causing disagreeable taste and odor at the conventional water treatment plant installed with pulsator clarifier patented by the French company $Degr{\acute{e}}mont$. The injection rate of Powdered Activated Carbon (PAC) into water was changed step wisely as we conducted jar tests in the laboratory and water treatment in the actual plant. 2-MIB concentration decreased linearly while geosmin did exponentially along with the injection rate of PAC at our jar tests. The removal efficiency of geosmin by PAC injection was considerably higher than that of 2-MIB. In the real pulsator clarifier, 2-MIB concentration started decreasing as the injection rate reached up to 10 mg/L of PAC. On the other hand, the concentration of geosmin in water decreased proportional to the injection rate of PAC. In the sand filtration, removal efficiencies of 2-MIB and geosmin on July were much higher than those on March. It was carefully suggested beforehand and found afterwards that general microorganisms notably existed in the sand filter with no chlorine in filter influent and backwash water and the sand filter biologically activated removed much more odor compounds. It was considered as the reason why the removal efficiency of 2-MIB and geosmin was increased. The microbial activity maybe increased in summer with water temperature rising and low filtration rate possibly increased contact time between odor compounds and general microorganisms.

• Journal of the Korean Society of Food Culture
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• v.25 no.5
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• pp.607-614
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• 2010

Changes in major volatile odor components (VOC) and sensory properties of kimchi during ripening for 4 days were investigated, and major VOCs of the raw materials of kimchi were also analyzed. Seven of eight major VOCs of kimchi originated mainly from garlic, while one originated from ginger. During 4 days of kimchi ripening, the amount of ethanol, which was substantially higher than that of other VOCs, increased continuously but decreased slightly on the fourth day. The amount of diallyl disulfide decreased during ripening, while that of allyl mercaptan decreased on the first day and increased slightly thereafter. The amount of methyl allyl sulfide, diallyl sulfide, and methyl trisulfide increased continuously during ripening, while that of dimethyl disulfide and methyl propyl disulfide increased until the second day and decreased thereafter. Scores of overall acceptability, taste, and odor for kimchi ripened for 2 days were significantly higher than those of other samples (p<0.05). The correlation between scores of overall acceptability and the amount of dimethyl disulfide or methyl propyl disulfide was higher than that of other VOCs.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.11
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• pp.5056-5062
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• 2011

This study was carried out to decrease intrinsic objectionable odor, bitter and fishy taste and change the biobeneficial components (gastrodin and p-hydroxybenzyl alcohol) of Gastrodia elate Blume. First of all, Gastrodia elata Blume. was dipped in the rice-washed water and rice-bran solution fermented with Lactobacillus brevis and Lactobacillus plantarum. The objectionable odor, bitter and fishy taste were decreased considerably with the treatments. Gastrodia elata Blume. was also dipped in organic acids (10 different varieties). The result showed that the most effective treatment to reduce objectionable odor, bitter and fishy taste of Gastrodia elata Blume. was treated with 1.0% lactic acid. Eleven different kinds of volatile components such as acetaldehyde, formic acid ethyl ester, acetic acid ethyl ester, 4-methylphenol and 3-hydroxy-2-butanone were separated from Gastrodia elata Blume when treated with or without 1.0% lactic acid. 4-Methylphenol, which is an objectionable odor in Gastrodia elata Blume, decreased with the treatment of lactic acid. While the contents of gastrodin and p-hydroxybenzyl alcohol in Gastrodia elata Blume. increased by 20% when dipped in 1.0% lactic acid solution for 24 hours and steamed at $98^{\circ}C$ for 4 hours.