• Fibers and Polymers
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• 제7권3호
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• pp.255-261
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• 2006

There is increasing interest in the many beneficial aspects of green tea to human such as anti-carcinogenic, anti-aggregant, anti-allergic, anti-bacterial, anti-mutagenic, and anti-oxidant activities. Besides these beneficial aspects, it has been reported that green tea ingredients, especially polyphenolic families (i.e., catechin), have some UV protection property both in vivo and in topical applications. In this study, green tea extract was used as a dyeing stock for cotton and the UV protection property of the dyed cotton fabric was examined. To increase the affinity of cotton fiber to the polyphenolic components in the green tea extract, a natural biopolymer, chitosan, was used as mordanting agent. The effects of chitosan concentration in mordanting on the dyeing characteristics and the UV protection property were examined. Chitosan mordanted green tea dyed cotton showed better dyeing characteristic and higher UV protection property compared with the unmordanted green tea dyed cotton. As the chitosan concentration in mordanting increased, the dyeing efficiency and the UV protection property also increased. Therefore, adapting chitosan mordanting in green tea dyeing can increase the UV protection property of cotton fabrics to some extent.

• 한국조리학회지
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• 제5권2호
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• pp.133-146
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• 1999

Green tea is popular as health food these days and has effects of anti-cancer and an-agering. A various Foreign countries produce green health cookie adding the first, the second and third classes green tea on a commercial. The cookie is produced by wheat flour adding 4% green tea. The changes of taste depending on the quality of green tea are examined through the five sense and the mechanical inspection. The results are as follow: First, as the quality of green tea is higher score is achieved. Second, as the quantity of green tea is increased, the goods are harder in the five sence inspection. Third, as the quality of green tea is higher, brightness is lower in the measurement of color. Therefore, this study indicates that it is desirable to use the good qualify of green tea in case of producing cookie on a commercial scale.

• Journal of Biosystems Engineering
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• 제41권2호
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• pp.85-92
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• 2016

Background: The same plant, Camellia sinensis, is used to produce all types of tea, and the differences among the various types arise from the different processing steps that are used. Based on the degree of fermentation, tea can be classified as black, green, white, or oolong tea. Of these, black tea is the most or fully fermented tea. The oxidized polyphenolic compounds such as theaflavins (TF) and thearubigins (TR) formed during fermentation are responsible for the color, taste, flavor, and aroma of black tea. Results: Research indicates that an optimum ratio of TF and TR (1:10) is required to ensure a quality cup of tea. The concentrations of TF and TR as well as desirable quality characteristics increase as fermentation time increases, reaching optimum levels and then degrading if the fermentation time is prolonged. It is also necessary to control the environment for oxidation. There are no established environment conditions that must be maintained during the fermentation of the ruptured tea leaves. However, in most cases, the process is performed at a temperature of $24-29^{\circ}C$ for 2-4 h or 55-110 min for orthodox tea or crush, tear, and curl (CTC) black tea, respectively, under a high relative humidity of 95-98% with an adequate amount of oxygen. Conclusion: The polyphenolic compounds in black tea such as TF and TR as well as un-oxidized catechins are responsible for the health benefits of tea consumption. Tea is rich in natural antioxidant activities and is reported to have great potential for the management of various types of cancers, oral health problems, heart disease and stroke, and diabetes and to have other health benefits such as the ability to detoxify, improve urine and blood flow, stimulate, and improve the immune system.

• Nutrition Research and Practice
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• 제5권1호
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• pp.20-27
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• 2011

We conducted this study to examine the effects of safflower seed granular tea containing physiologically active polyphenols on antioxidative activities and bone metabolism. Forty postmenopausal women ages 49 to 64-years were recruited from Daegu and Gyeongbuk and were randomly assigned to either a safflower tea supplement (Saf-tea) group (n=27) or a placebo group (n=13). The Saf-tea group received 20 g of safflower seed granule tea per day containing a 13% ethanol extract of defatted safflower seeds, whereas the placebo group received a similar type of tea that lacked the ethanol extract. No significant changes in nutrient intake for either the placebo or Saf-tea groups were observed before or after the study period, except vitamin A intake increased after 6 months in the Saf-tea group. Dietary phytoestrogen intakes were similar in the Saf-tea group (60.3 mg) and placebo group (52.5 mg). Significant increases in plasma genistein and enterolactone were observed in the Saf-tea group. After 6 months of supplementation, serum levels of antioxidant vitamins such as a-tocopherol and ascorbic acid increased significantly, and TBARS levels decreased in the Saf-tea group compared to the placebo group. Serum osteocalcin levels were reduced (P<0.05) in the Saf-tea group after 6 months, whereas serum osteocalcin did not change in the placebo group. Urinary deoxypyridinoline/creatinine excretion was not different between the two groups at baseline, and did not change in either group after 6 months. Bone mineral density decreased significantly in the placebo group (P<0.01) but not in the supplemented group. It was concluded that polyphenols (72 mg/day), including serotonin derivatives, in the Saf-tea had both antioxidant and potential bone protecting effects in postmenopausal women without liver toxicity.

• 한국식품영양과학회지
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• 제26권5호
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• pp.827-830
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• 1997

Sensory evaluation method was used to develop a type jujube tea the organoleptic properties were evaluated with regard to the optimum sugar content, clarity, drinking temperature and fruit pulp content of the jujube tea. Clarified jujube tea extracted from 25% by weight of dry jujube fruits and 75% water was preferred to those from 15%, 20% and 30% jujube fruites although those from 20% and 30% were not significantly different at 5%level. In spite of the average acceptability score of cloudy jujube tea with 5% of added fruit pulp was not significantly different from that of clarified one, the more fruit pulp in the tea products the worse its acceptability. Cold jujube tea was preferred to warm and hot ones, but these were not significantly different.

• 한국식생활문화학회지
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• 제20권6호
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• pp.675-682
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• 2005

This study was aimed to determine microbiological quality by adding green tea extracts to chicken meat salad. For this study, Chicken meat salad were prepared with two production method. (method 1: addition of green tea extracts to boiling phase, method 2: addition of green tea extracts to salad dressing) Microbiological effects of green tea extracts were assessed during production process by measuring process time, temperature, pH and Aw and determining total plate counts and coliforms. Effects of green tea extracts on total plate counts and coliforms were observed during holding at 3, 10, $25{\pm}1^{\circ}C$ for 12 hours. Green tea extracts improved the microbiological quality and showed antibacterial properties when they are added to chicken meat salad.

• 한국전통조경학회지
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• 제38권3호
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• pp.64-74
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• 2020

고품질의 차 생산과 풍요로운 생물다양성의 보전으로 환경과 공생하는 보성 차농업 시스템의 가치를 인정받아 2018년 국가중요농업유산으로 지정받았으나 농업인구의 고령화로 농업시스템의 보전과 전승이 위협받고 있는 실정이다. 이에 본 연구에서는 보성 차농업시스템의 보전과 차세대 전승 방안의 하나로 세계중요농업유산시스템의 등재를 제안하고자 한다. 본 연구는 세계중요농업유산과 국가중요농업유산, 보성 차농업 시스템을 검토하고, 2020년 3월에서 5월까지 석 달간 전라남도 보성군 차 재배 농민을 대상으로 방문과 전화 인터뷰를 통한 실태조사와 심층면접조사를 통하여 보성 차 농업인구의 초고령화 실태를 확인하였다. 조사 결과, 보성 차농업인의 평균연령은 69.4세였으며, 2세대 이상 전승 가구는 36%(54명)에 불과하였고, 79.4%(119명)의 농가의 차 수입 의존도가 90% 이상인 것으로 나타났다. 심층면접 결과, 보성 차 재배농업인의 고령화에 대해 우려를 나타냈으며, 세계중요농업유산 등재는 보성 차에 대한 신뢰도와 인지도 향상으로 이어져 보성 차농업시스템의 보전과 전승에 도움이 될 것이라고 응답하였다. 세계중요농업유산 등재는 보성 차 농업시스템의 농업가치를 전 세계와 공유하고 미래에 전승할 수 있다는 점에서 더없이 훌륭한 자산이 될 것이다.

• 한국식품과학회지
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• 제54권2호
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• pp.228-234
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• 2022

Various types of tea have been cultivated to obtain different flavors and enhance their functional properties. The objective of this study was to investigate the physicochemical properties of γ-aminobutyric acid (GABA) teas produced from commercial Korean green, white, and black teas. The concentration of total minerals was reduced in GABA green tea and GABA white tea but was improved in GABA black tea. The essential, non-essential, and total free amino acid contents were remarkably increased in the GABA teas. The amino acid GABA content was increased by 561.00 and 294.20 times in GABA white tea and GABA black tea, respectively. The antioxidant potential was not reduced, although the total polyphenol and total flavonoid contents decreased in GABA green tea and GABA black tea. The results indicated that the overall nutritional value of commercial green, white, and black teas could be improved by processing them into GABA teas.

• 한국식품조리과학회지
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• 제26권5호
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• pp.567-574
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• 2010

Pork patties were formulated with either steam-dried green tea power or freeze-dried raw tea leaf powder, and the quality characteristics of these products were monitored. Proximate analysis of tea powder contained 17.80~19.85%, 4.70~5.73%, and 5.60~5.77% (as is) crude protein, crude fat, and crude ash, respectively. There were no significance differences in pH among the samples. Chromaticity tended to decrease brightness ($L^*$) and redness ($a^*$), and there were significant differences in yellowness ($b^*$) as the added amount of tea power was increased. For texture, hardness increased as more green tea powder was added. Thiobarbituric acid reactive substances (TBARS) and volatile basic nitrogen (VBN) values increased after storage for 12 days, whereas samples formulated with green tea powder showed lower TBARS and VBN values compared to control groups. Sensory panelists showed preference for samples with green tea powder added compared to the control group.

• 한국식품조리과학회지
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• 제17권3호
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• pp.246-254
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• 2001

Effects of added green tea powder and Angelica keiskei powder on the quality characteristics of Yukwa were examined for the purpose of improving functioanality and variety of Yukwa, and usage of green tea Powder and Angelica keiskei. Dietary fiber contents of green tea powder were 5.2% soluble dietary fiber, 22% insoluble dietary fiber, while Angelica keiskei contained 28.9% soluble dietary fiber, 29.6% insoluble dietary fiber. Expansion rate of yukwa was 3,675% for control and the rates were slightly decreased as the addition level increased. Although Yukwas added 6% green tea and angelica keiskei powder were harder than the others when determined by rheometer, sensory evaluation results showed that hardness and mouthfeel were soft without any significant difference among the control and experimental samples. And internal structure of 4 and 6% green tea powder and those added angelica keiskei at three levels were evaluated by sensory panel as moderately compact. Overall acceptability of yukwa added 2% green tea Powder was the best of all while yukwas added angelica keiskei at three levels were evaluated as good. The results of peroxide value and TBA value showed that green tea powder had stronger antioxidative property than angelica keiskei. In conclusion addition of green tea powder by 2% level and angelica keiskei powder up to 4% would give us beneficial effects in the aspects of functionality and storage life of yukwa without any detrimental effects on the quality characteristics of it.