• Journal of the Korean Society of Food Culture
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• v.36 no.3
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• pp.300-307
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• 2021

In this study, consumers' perception and consumption behavior of blended tea were investigated. Also, consumer perception of Siberian chrysanthemum, consumption behavior, and awareness of efficacy were investigated. As a result of the survey, it was confirmed that it was necessary to develop a blended tea with taste and flavor characteristics that consumers prefer, having the capability of relieving stress, and preventing cold or respiratory disease. In addition, the degree of recognition of Siberian chrysanthemum was very low, and the recognition of the efficacy appeared in the order of 'cold relief' and 'respiratory disease relief'. Factor analysis results, safety attributes, health attributes, product attributes, marketing attributes, and sensory attributes were factorized into five factors, and after analysis, it was concluded that the sensory attributes of taste and aftertaste were considered the most important. Consumers surveyed appeared to consume blended tea for 'relieving mood or stress relief', to enjoy the taste, and to prevent cold or respiratory diseases. Siberian chrysanthemum displays efficacy in cold relief and relief of respiratory diseases. Therefore, developing Siberian chrysanthemum as a blended tea could be a practical application that can expand the range of its use, making it more popular and increase its commercial applications.

• Proceedings of the Membrane Society of Korea Conference
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• 2004.05a
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• pp.199-202
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• 2004

Membrane technology is widely employed as a means of producing various qualities of water from surface water, well water, brackish water and seawater. This is also used in industrial wastewater treatment and its recycling process. A large volume of wastewater is generated by the steel industry. Presently, the treated wastewater from the steel industry cannot be recycled, because some of its components cause either direct or indirect problems.(omitted)

• Korean Journal of Food Science and Technology
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• v.40 no.5
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• pp.485-490
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• 2008

In this study, organic tea leaves were characterized with the aim of developing an organic beverage process. The green tea leaves grown using organic farming techniques were collected in Haenam, Korea. Catechins in green tea leaves were extracted by chloroform and ethyl acetate and these were then analyzed quantitatively and qualitatively by HPLC (high pressure liquid chromatography). The color and pH values of the green tea extracts were also measured. The catechin levels of April-harvested, May-harvested and June-harvested, semi-fermented leaves at 0.5% were 66.24, 29.19, 57.11, and 5.27 ${\mu}g/mL$, respectively. Among the detected catechins, the level of (-)-epigallocatechin gallate was the highest while that of (-)-epigallocatechin was not detected. The June-harvested leaves were selected as raw material for development of the green tea beverage, based on the levels of catechins, economic viability and yield of tea extract. As the level of extract increased, the levels of catechins of 0.1, 0.2, 0.5% also increased by 1.5, 11.78 and 41.01 times. From the results of the sensory evaluation of June-harvested leaf-extract, the sensory score of color was the highest in 0.1%, while the flavor and overall quality were the highest in 0.2%.

• Journal of Nutrition and Health
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• v.12 no.1
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• pp.69-75
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• 1979

Stevia rebaudiana Bertoni M. can be cultivated in Korea as a new sweetness resource. It seems possible that stevioside the sweet substance extracted from the leaves of Stevia rebaudiana Bertoni M. can be used instead of saccharin. In order to obtain the fundamental data due to natural sweetening materials used of as additives to food stuffs such as coffee and tea etc. It was investigated to reduce the calories from coffee and tea without reducing the conventional sweetness, drinks sweetened with mixtures of stevioside and sucrose were prepared. The results obtained are as follows: 1) Mixture of 50% stevioside 40 mg (0.04%) (A) and 1.5% sucrose, 95% stevioside 20 mg (0.02%) (B) and 2.0% sucrose, and 50% stevioside 60 mg (0.06%) (A) and 95% stevioside 40 mg (0. 04%) (B), the sweetness of which in coffee corresponded to that of 7% sucrose in the drink, was prepared. 2) Mixture of 50% stevioside 60 mg (0.06%) (A) and 1.5, 2.0, 2.5% sucrose, 95% stevioside 40 mg (0.04%) (B) and 1.5, 2.0% sucrose, and 50% 80 mg (0.08%), 95% 60 mg (0.06%) (A,B), respectively the sweetness of which in tea corresponded to that of 7% sucrose in the above drink, was prepared. 3) Sucrose saving of 21.42-28.57% compared to equally sweet sucrose-sweetened coffee and tea could be achieved without deterioration of other taste qualities.

• Korean journal of food and cookery science
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• v.27 no.5
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• pp.567-575
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• 2011

This study was investigated the antioxidative and antimicrobial activities of a water extract (70$^{\circ}C$) of traditional Korean teas (rose, chrysanthemum, pine needles, mulberry, persimmon leaves, and green tea). Total phenol contents in rose, chrysanthemum, pine needles, mulberry, persimmon leaves, and green tea were 272.8, 74.6, 153.5, 73.5, 69.5, and 260.8 mg tannic acid/g extract, respectively, whereas total flavonoid contents were 75.1, 47.8, 26.8, 40.0, 27.9, and 99.5 mg quercetin/g extract, respectively. The order of electron donating abilities of Korean traditional tea water extracts (1 mg/mL) were : rose (96.8%) > green tea (95.3%) > pine needles (71.3%) > chrysanthemum (36.8%) > mulberry (28.9%) ${\qeq}$ persimmon (28.8%). The order of nitrite-scavenging abilities at pH 1.2 (2 mg/mL) was green tea > rose > pine needles > chrysanthemum ${\qeq}$ mulberry ${\qeq}$ persimmon. The order of hydroxyl radical scavenging activity (5 mg/g) was chrysanthemum > mulberry > rose > persimmon leaves > pine needles > green tea. Rose extracts showed antimicrobial activity against Micrococcus luteus, Bacillus cereus, Salmonella enteritidis, and E. coli, whereas green tea extracts showed strong antimicrobial activity aginst S. enteritidis.

• Journal of the East Asian Society of Dietary Life
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• v.17 no.3
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• pp.409-416
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• 2007

This study investigated changes in the catechin and alkaloid contents of Bosung green tea during different manufacturing processes and storage periods, using HPLC and UV-VIS spectrophotometer analysis. For changes in the catechin and alkaloid contents by roasting technique, we found that EGCG, CG and GCG decreased just slightly by processes performed before roasting, rather than after roasting. In addition, theobromine, caffeine, and ECG changed minimally throughout all the processes. For changes in the catechin and purine alkaloid contents of the green tea leaves during storage, EGCG, ECG, and CAF decreased considerably in the green tea stored at temperatures of $5^{\circ}C$ and $25^{\circ}C$, and they decreased by $20{\sim}30%$ after storage for 1 year. However, a quantitative difference was hardly observed in the catechin and alkaloid contents regardless of storage temperature.

• Food Industry And Nutrition
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• v.10 no.2
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• pp.50-59
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• 2005

• The Korean Ginseng Research and Industry
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• v.6 no.1
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• pp.14-24
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• 2012

• Korean Journal of Food Science and Technology
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• v.38 no.1
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• pp.5-9
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• 2006

Method for separation and quantification of methylxanthins, catechins, and theaflavins in Korean commercial teas (green, oolong, and black teas) was developed using reversed phase high-performance liquid chromatography (HPLC). After extraction with hot water, tea compounds were separated on Inertsil ODS-3v $(5\;{\mu}m)$ column, eluted with gradient of 7% acetonitrile and 93% of 20 mM phosphate buffer mixture for 7 min. Column effluent was monitored at 270 nm. This technique was effective for analyses of m methylxanthins, catechins, and theaflavins in teas and biological samples. In green and oolong teas, two kinds of methylxanthins and 7 of catechins were identified, whereas 4 theaflavins were only identified in black tea. Among seven catechins in green and oolong teas, EGCG showed highest amount, whereas ECG was highest in black tea. (theaflavins were found only in black teas) In all teas, theobromine content was lower than that of caffeine.

• Journal of Nutrition and Health
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• v.12 no.1
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• pp.77-82
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• 1979

The purpose of this study was to search for a mixture of stevioside and sucrose, the sweetness of which in soft drink such as cocoa and ginger tea were almost equal the sweetness of commomly used 7% sucrose in the drinks. Results obtained by the present experiment were as fellows: 1) Mixture of 50% stevioside 40mg (0.04%) (A) and 2.0% sucrose, 95% stevioside 40mg (0.04%) (B) and 1.0% sucrose, and 50% and 95% stevioside 60mg (0.06%) (A,B) respectively, the sweetness of which in ginger tea corresponded to that of reference in the drink. 2) Mixture of 50% stevioside 40mg (0.04%) (A) and 2.0% sucrose, 95% stevioside 20mg (0.02%) (B) and 2.0% sucrose, and 50% stevioside 40-60mg (0.04-0.06%) (A) and 95% stevioside 40-60mg (0.04-0.05%) (B), the sweetness of which in cocoa is equal to that of standard sucrose in the drink. 3) The mixture contains low energe, and also the after-taste of stevioside was not detected in the above drinks.