• The Korean Journal of Community Living Science
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• v.18 no.1
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• pp.107-129
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• 2007

The purpose of this research is to understand features of the present condition of green tea food by analyzing the data on tea foods presented in Korean literature after the 1990's (two articles from professional journals related to tea culture, and three books related to tea food). The main conclusions are as follows: 1. It is found from separating 354 different kinds of green tea foods into three categories - main dishes, side dishes and desserts - that there are 137 kinds of side dishes, 123 kinds of desserts, and 94 kinds of main dishes from green tea foods. Upon dividing these into smaller categories, there are 40 rice dishes, 27 noodle dishes, 18 gruel dishes and 9 dumpling dishes found among the main dishes; 26 pan fried dishes, 24 potherb/cooked potherbs dishes, 17 deep-fried dishes, 15 soup/broth dishes, 14 grilled dishes, 11 smothered dishes, 10 hard -boiled/fried dishes, 6 kimchi dishes, 4 dried food dishes, 4 jelly dishes, 4 stew dishes, and 2 raw fish dishes among the side dishes; and 37 snack dishes, 36 punch/drink dishes, 26 rice cake dishes, and 24 bread dishes are found among the desserts. 2. There are 201 kinds of green tea foods using powders, 107 kinds using wet tea leaves, 61 kinds using dry tea leaves, 57 kinds using water of drawn tea, and 17 kinds using wild tea leaves, according to analysis of teas used for green tea foods. There is more use of powder for snacks, punch and drinks, rice cakes, noodles, and breads, and more use of wet tea leaves for rice, pan fried food, and potherb/cooked potherb dishes. It is also shown that there is more use of water from drawn tea for rice, punch and drinks, noodles, and gruels, more use of dry tea leaves for snack, rice, breads, and more use of wild tea leaves for deep-fried and pan fried kinds of tea foods.

• The Korean Journal of Food And Nutrition
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• v.11 no.5
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• pp.521-527
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• 1998

Removabilities of heavy metals(Cd and Pb) by the tea materials (barley-tea, corn-tea, jasmin-tea, brown rice-green tea, black-tea, cassia tora-tea, persimmon peel-tea, and rice-tea) in the tea-water were studied in the various conditions ; particle size of tea (20, 40, 70 mesh), concentration of heavy metal (25, 50, 100 ppm) and extraction temperature(20, 30, 50, 100$^{\circ}C$). The removabilities by the tea solids were increased as the particle size decreased, concentration of heavy metal increased, and extracting temperature increased. Of the nine kinds of tea, Cd and Pb removability by jasmin-tea was highest. In addition, heavy metal removability by cassia tora tea was better than that of other tea as extraction temperature was increased.

• Journal of the East Asian Society of Dietary Life
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• v.9 no.3
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• pp.363-369
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• 1999

The heavy metal removability of four kinds of tea was investigated in the various conditions: particle size of tea(10, 35. 70, 100 mesh), concentration of heavy metal(25, 50, 100ppm) and extraction temperature(30. 50, 70. 10$0^{\circ}C$). The removabilities by the tea solids were increased as the particle size decreased, concentration of heavy metal increased, and extracting temperature increased. Of the four kinds of tea Pb, Cd and Cu removability by Eucommia ulmoides Oliv tea was the highest. In addition, heavy metal removability by Schizandra chinensis Baillon tea was better than that of other tea as extraction temperature was increased.

• Food Science and Preservation
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• v.12 no.1
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• pp.68-74
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• 2005

This study was carried out to analyze to the flavor components of Lindera obtusiloba BL leaf teas by different processing methods. 81 kinds of flavor components in the masted tea, 78 in the roasted tea after steaming, 88 in the withered tea, 86 in the fermented tea, 72 in the steamed tea, and 89 in the air dried tea ware by GC/MS. Hydrocarbones in Lindera obtusiloba BL leaf teas were 45 kinds of $\beta-piepne$, and 16 kinds of alcohols such as Linalool, n-octanoal, phenyl acetaldehyde, $(-)-\alpha-terpineol$, elemol, and cholest-5-en-3-ol. 11 kinds of ketones sachas 2-ethyl-2- propyl-cyclohexanone, and 8 kinds of aldehydes sach as phenyl acetaldehyde, tetradecanal, 10-undecanal, 4-Bromo-2-methylbutanal were found. Esters were methyl 9,12,15-octadecatrienate, didodecyl phthalace, 1,2-benzenediccarbaboxy acid-bis (2-ethylhexyl)ester and phenols was 2,6-bis(1,1-dimethylethyl)-4-methyl-phenol.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2003.10b
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• pp.33-33
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• 2003

Most of leaf teas, except flower tea, were considered as good materials with basic conditions for tea manufacture because water content was below 6 %, Crude protein was the greatest component in roasted young leaf tea, crude fats in roasted mature leaf tea and ashes in fermented young leaf tea. Caffein were present as the highest amount(5.18%) in steamed mature leaf tea, showing less amount than greenp teas. Catechin were contained as the highest amount in all kinds of teas, especially fermented young leaf tea. was the highest(9.57%). Tannin, which highly related with tea quality including astringent taste, color and perfume, were present as the highest amount in fermented young leaf tea.(중략)

• Journal of Korean Society of Environmental Engineers
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• v.37 no.9
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• pp.511-516
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• 2015

On this study, we investigated the removal characteristics of residual chlorine and DBPs in tap-water during boiling. Also we investigated the releasing characteristics of essential minerals in infusion tea. While recent studies focused on removal mechanisms of harmful heavy metals in infusion tea, this study tried to suggest the way to drink tap-water healthier and safer by examining releasing mechanisms of essential minerals in infusion tea. As a result, residual chlorine(initial conc. was 0.7 mg/L) was all removed in 20 minutes after heating and DBPs (the sum of THMs, HAAs and CH) were removed up to 65%. 6 kinds of essential minerals (Ca, K, Na, Mg, S, P) were released from 5 kinds of infusion tea (barley tea, corn tea, brown rice tea, cassia seed tea, solomon's seal tea) on the market. In cassia seed tea, the amount of essential minerals released from tea showed the highest values, 9.6 mg/g, and brown rice tea was the lowest, 1.6 mg/g. Particularly, the released amounts of potassium, playing a key role in human body in maintaining normal blood pressure, cell metabolism and enzyme action, showed relatively high. Through this study, we got to know that essential minerals can be obtained up to 40% of recommended nutritional intake for Korean by boiling tap-water with infusion tea.

• Korean Journal of Food Science and Technology
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• v.18 no.1
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• pp.16-23
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• 1986

Physico-chemical and sensory characteristics of 28 black tea samples prepared by oaring the mixing ratio of 1 kind of Korean and 9 kinds of foreign black tea were determined, and their relationship was statistically analysed. Korean black tea was found to be lower in bulk density, caffeine, theobromine, crude protein, theaflavin, thearubigin and soluble solids, and higher in Hunter L- and b- value, neutral detergent fiber, calcium and ratio of oxidized matter as compared with foreign black tea. The palatability for 8 kinds of foreign black tea was generally increased by mixing with Korean black tea. The number of black tea whose palatability were higher than that of Korean black tea was 12, which was mostly mixed black tea. Theaflavin. Hunter a-value, soluble solids of the tea infusion, and potassium of the manufactured tea were the major guiding characteristics as a result of stepwise multiple regression analysis, and about 67% of the total variations in the palatability of black tea could be explained by the regression equation formulated by the preceding 4 characteristics.

• Culinary science and hospitality research
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• v.12 no.4 s.31
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• pp.213-224
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• 2006

This study was to investigate the factors affecting drinking Korean traditional beverages and the drinking habits of college students in Seoul. The research was carried out by asking them to drink 10 kinds of traditional drinks. They were composed of 45.5% of boys and 54.5% of girls who were $18\sim21$ years old, studying food related science (63.9%), and mostly (86.6%) living in a nuclear family in collective residents (60.4%) like an apartment. The number of students whose family's monthly incomes were over 3 million won was the largest as 37.1%. Their mothers were housewives (58.4%) mostly aged $46\sim50$ as 47.0%. In the research on the preference of students for the traditional drinks, most of them, 78.7%, showed their liking for the drinks because of their good taste (61.%). The number of students who answered they got the drinks by homemaking was the largest as 39.6%. Most of them, 66.3%, preferred fruit drinks, 19.8% soda drinks, 11.4% traditional drinks and 2.5% functional drinks. 31.2% of the drinks mostly taken at home was green tea, followed by sweet rice drink, Shik-hae. Among the drinks coming into the market, sweet rice drink was preferred in general as 25.7%, and the next was green tea 16.8%, ume drink (Maesil tea) 14.9%, rice tea 13.9%, fruit punch (Sujeonggwa) 11.4%, black tea 7.9%, honey tea 4.5%, ginseng tea 2.5% and jujube tea 2.5%. In the research on 'whether the students had experience preparing the traditional drinks or not', many of them, 62.4%, answered "No". And in the questionnaire asking on 'whether they liked to receive a training on making traditional drinks or not', 87.6% of them showed their wish to get the training. In the question on the reason why the students did not like to take the training on traditional drinks, the number of students who answered that it was complicated and hard to prepare was the largest as 53.0%.

• The Korean Journal of Food And Nutrition
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• v.7 no.4
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• pp.253-258
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• 1994

This thesis is to analyze the ingredients of five-fruit tea depending on extraction time as a basic experiment for quality improvement and industrialization of traditional Korean beverage. According to extraction time, the acidity of the tea is 2.4% at 30 minutes, 2.3% at 50 minutes and 1.7% at 70 minutes, and soluble solid is 0.22 g, 0.31 g and 0.41 g. The pH of five-fruit tea, which is 4.70, 4.85 and 4.98 at each time, and total sugar is 54.01 m9, 108.82 m9 and 142.92 mg as extraction time increases. The total amount of free sugars is 1.14 mg, 1.36 mg and 2.17 mg, and glucose, surcose and fructose which are 98.2%, 92.6% and 92.6% of the whole percentage occupy the most part of free sugars. The total free amino acids content increases to 84.94 mg, 99.67 mg and 120.40 mg. The five kinds of amino acids like serine, glutamic acid, threonine, proline and alanine amount to 94.5%, 93.6% and 94.7% at all. she variation in the percentage of free amino acids content in accordance with extraction time is as follows : threonine, extracted for 50 minutes, is reduced considerably and glutamic acid decreases gradually as extraction time increases. When proline is extracted for 50 minutes, it's rate of increase Is most high.

• Journal of the East Asian Society of Dietary Life
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• v.23 no.5
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• pp.533-545
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• 2013

A type of Korean traditional cookies, yackwa is composed of ingredients which serve as good medicine to people. Further, it has a priceless value and possibility to be a healthy functional dessert. For this study, we developed variable yackwa, containing red-ginseng powder and green tea powder, in order to target the foreign market as well as to investigate the perception and preference of yackwa. The test sample for the control group, yackwa is made of flour, sugar, baking powder, sesame oil and alcohol. For the experimental group, yackwa contains red-ginseng and green tea powder (3, 6, 9, 12%). The investigation period was May 14th, 2013 and the total number of participants was 100. The investigation applied a consumer survey method by filling out a questionnaire while tasting 9 kinds of yackwa samples. They were used for frequency, one-way ANOVA and Pearson's correlation analysis with SPSS 19.0. In the yackwa perception survey, the result indicated that 52.0% of the customers replied 'Do not know well' and 'Do not know at all' which conveys that the perception of yackwa is very low. In contrast, the perception of the red-ginseng and green tea which are functional ingredients is high and the customers tend to prefer the taste and flavor of green tea than red-ginseng. And they prefer the yackwa containing 3% of red-ginseng and green tea powder compared to other ratio contents in the overall preference, color, taste, flavor, odor, degree of greasiness and texture. When people who have a higher perception of yackwa, they tended to prefer the color of red-ginseng yackwa and dislike the color of green tea yackwa. And the more people prefer the taste of green tea, the higher in overall preference, color, taste, flavor, and odor preference.