• Title/Summary/Keyword: White tea

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Physicochemical Properties and Antioxidative Activities of White Radish Tea by Different Preparation Methods (가공 방법을 달리한 무차의 이화학적 품질 특성과 항산화 활성)

  • Kim, Min-Ji;Park, Jong-Dae;Sung, Jung-Min
    • Culinary science and hospitality research
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    • v.24 no.1
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    • pp.73-81
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    • 2018
  • The objective of this study was to investigate their physicochemical properties and antioxidant activities of white radish teas such as pH, color value, total polyphenol contents, total flavonoids, DPPH radical scavenging activity, reducing power and sensory evaluation. They were processed by drying(AD), drying and roasting(ADR), steaming and drying(SAD), and steaming, drying, and roasting(SADR). As a result, the pH of ADR, and SADR tended to be significantly lowered and SADR was the lowest at $5.48{\pm}0.14$(p<0.001). Additionally, ADR and SADR were significantly different in color and browning value, compared to AD and SAD. There was no significant difference in reducing sugar content depending on processing methods. The total polyphenol content and total flavonoid content of the teas were significantly increase after roasting. DPPH radical scavenging activity was significantly higher in ADR and SDAR than in AD or SAD by 1.1~1.5 times(p<0.05). Compared with ADR and SADR after roasting, the sensory characteristics of AD and SAD were significantly lower than those of roasted ADAD and SAD, respectively. From the above results, it was concluded that the roasting process is a major process that affects the physicochemical quality characteristics and antioxidant activities.

Properties of Extracts from Extruded Root and White Ginseng at Different Conditions (압출성형 공정변수에 따른 건조수삼과 백삼 압출성형물의 침출속도 및 침출물 특성)

  • Kim, Bong-Soo;Ryu, Gi-Hyung
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.34 no.2
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    • pp.306-310
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    • 2005
  • The comparison in release rate constant and properties of extracts from extruded raw ginseng and extruded white ginseng was conducted to apply extrusion process for manufacturing of released ginseng tea bag. Dry raw ginseng and white ginseng powder were extruded at 20∼30% moisture content and 200∼300 rpm by using an experimental twin-screw extruder. Browness and redness (both indicated the releasing of saponin and ginsenosides) were increased with the increase in the screw speed and the decrease of moisture content. Crude saponin and water solubility index (WSI) of both ginseng also share the same behaviour against the level of screw speed and moisture content, as well as browness and redness. The particle size effects of extruded raw ginseng at 20% and 28% moisture content on absorbance of released extract at 260 up to 560 nm, WSI, and water absorption index were determined. While particle size decreased from 800∼1000 nm to 200∼500 nm, absorbance and WSI are decreased. Absorbance and WSI shown increasing level while moisture content was decreased. In conclusion, the formation of pores by expansion and disruption of cell wall in extrusion cooking were obviously responsible to increase the amount of released extract of extruded ginseng and its WSI as well. The extrusion process turns out be the efficient process for manufacturing of commercial ginseng tea product than those of other thermal processes.

Milk and Beverage Preference of College Students (대학생들에 대한 우유와 음료수의 기호성)

  • Kim, Hyun-Dae;Kim, Dong-Soo;Kim, Song-Suk
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.23 no.3
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    • pp.420-428
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    • 1994
  • The purpose of this study was to determine relationship among the observed frequencies of 12 beverages selected by college men and women according to sex, age, race and academic classification and to estimate consumption of milk according to sex, age, race and academic classification. The instrument consisted of a check list and four questions. The sample of 282 subjects, 149 college men and 133 college women, was made by the accidental choice method. Observations occurred in the university center cafeteria at the dinner meal. The significant relationship s were sex and race in association with beverage selections by all subjects. The proportion of men in the distribution who selected regular , carbonated soft drinks and the proportion of white students who selected any of the carobnated soft drinks were the influencies. The result of the study indicated that carbonated soft drinks were the most preferred items followed by milk, water, iced tea, fruit juices, coffee, cocoa, and tea.

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The Effects of the Cutting Length of Paper Mulberry Bast Fiber on Pulping and Hanji Properties(I) - White bast of Korea grown paper mulberry - (닥나무 인피섬유의 절단장이 펄프화 및 한지의 물성에 미치는 영향(제1보) - 국산 닥 백피의 특성 -)

  • Lim, Gang-Hyouk;Choi, Tae-Ho
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.40 no.2
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    • pp.57-64
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    • 2008
  • In general, the entire of paper mulberry bark, which is not cut into pieces with an appropriate length, have been used in the pulping. This kind of pulping method couldn't accomplish the improvement of beating and sheet forming efficiency. For this reason, we investigated the effects of the cutting length of paper mulberry bast fiber on pulping and Hanji (Korean traditional paper) properties, in order to develop high quality Hanji manufacturing process. The cutting length variation of paper mulberry white bast did not great effects on pulp yields. The pulp yields based on pulping methods were sulfomethylated pulping av. 57.4%, alkali-hydrogen peroxide pulping av. 55.4%, and alkaline pulping av. 53.5% respectively. The optical properties such as brightness, opacity, scattering coefficient, and absorption coefficient were slightly improved by the increase of paper mulberry white bast cutting length. The increase of paper mulberry white bast cutting length resulted in poor sheet formation. Physical properties such as breaking length, TEA, tear index, burst index, and folding endurance were slightly improved by the increase of cutting length. The modified pulping processes, which used sulfomethylated method and alkali-hydrogen peroxide method, showed better pulp and sheet properties than conventional alkaline pulping.

Developed Health Tea Using Flowers of Robinia Pseudoacacia L. (아까시나무 꽃을 이용한 건강 차 개발)

  • Park, N.B.;Chung, J.G.
    • Journal of Practical Agriculture & Fisheries Research
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    • v.20 no.1
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    • pp.67-74
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    • 2018
  • This experiment was conducted to develop a healthy tea by fumigation, low temperature drying, drying and instant immersion using flowers of Robinia pseudoacacia L. that bloom in May in all regions of Korea. The drying was drying after fumigation treatment, low temperature drying, drying and instant immersion. The color of the flowers, beverage color, the sugar content, and the taste of the beverage were measured after changing the weight of the flowers. The change in the weight of flower tea was 11% ~ 12.5% of the body weight. The change in the color of the flowers appeared to be the lightest brown in the treatment of drying, and the other treatment area became turbidity white. The color of the beverage was yellowish from the tea treated with drying and became pale yellow when fumigation, low temperature drying and instant immersion. Sugar content was highest at 2.9brix from the drying and 2.6-2.7brix at the other three treatments. The taste was the best in the drying treatment, and the instant taste dipped in the tastes.

Eye Irritation, Skin Irritation and Skin Sensitization tests for Aloewhite in Animals

  • Kim, Hyung-Sik;Kwack, Seung-Jun;Kim, Kyu-Bong;Lee, Seung-Ki;Park, Hyun-Sun;Hong, Che-Young;Ahn, Mi-Young;Jo, Tea-Hyung;Oh, Sun-Tack
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 1996.04a
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    • pp.250-250
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    • 1996
  • Eye irritation, primary skin irritation and skin sensitization tests for Aloewhite were tested in New Zealand White rabbits and Hartley guinea pig. In primary skin irritation test of male New Zealand White rabbits, body weights were not significantly changed and primary Irritation Index(PII) was 0.47, indicating Aloewhite as mildly irritating material, In ocular irritation test, any injury on iris, conjunctival membrane, and cornea in New Zealand White rabbits was not observed. No injuries of the ocular mucous membrane were also recorded. Skin sensitization was tested in guinea Peg after intradermal and epicutaneous induction and graded I with zero % sensitization rate. These results indicate that Aloewhite was not considered to be irritant in test organs of animals.

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Quality Characteristics of Nelumbo nucifera G. Tea White Bread with Hemicellulase (헤미셀룰라아제를 첨가한 백련차 식빵의 품질 특성)

  • Kim, Young-Sook;Kim, Mun-Yong;Chun, Soon-Sil
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.37 no.10
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    • pp.1294-1300
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    • 2008
  • Nelumbo nucifera G. tea white breads were prepared by the addition of 0.01, 0.02, 0.03, and 0.04% hemicellulase to flour of the basic formulation. The experiments and control were then compared in terms of quality characteristics, including pH, total titratable acidity, fermentation power of dough expansion, specific volume, baking loss, moisture content, color, textural characteristics, external and internal surface appearances, and sensory qualities in order to determine the optimal ratio of hemicellulase in the formulation. There were no significant differences in pH and total titratable acidity of dough among the experiments. Fermentation power of dough expansion were increased as incubation time increased. Baking loss was the highest at the 0.04% addition level, while the lowest at the 0.01% level. As hemicellulase content increased, pH, hardness, and fracturability of bread decreased, while total titratable acidity, specific volume, and resilience increased. Water content and lightness were the highest in the control bread samples, and yellowness was maximal in the 0.01% group. Bread made by the addition of hemicellulase had significantly higher greenness and flavor than the control group. Color, consistency, and springiness of crumb, density and uniformity of crumb pore, softness, chewiness, overall acceptability, lotus leaf flavor, delicious taste, astringency, bitterness, and off-flavor were not significantly different among the samples. The results indicate that adding 0.02$\sim$ 0.03% hemicellulase in N elumbo nucifera G. tea white bread is optimal for quality and provides a product with reasonably high overall acceptability.

Antithrombotic Activities of Cheongkookjang and Cheongkookjang Fermented with Green Tea or Mugwort (청국장 및 녹차, 쑥이 첨가된 청국장의 항혈전 활성)

  • Lee, Kyung-Ae;Jang, Jeong-Oak;Yoon, Hye-Kyung;Kim, Moo-Sung
    • Korean Journal of Microbiology
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    • v.43 no.4
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    • pp.298-303
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    • 2007
  • Antithrombotic activities of water extract of cheongkookjang and cheongkookjang fermented with green tea or mugwort were evaluated on some antithrombosis related activities in vitro and thrombotic death inhibition in vivo. Cheongkookjang made of white soybean (Glycine max) or black small soybean (Rhynchosia nulubilis) showed potent antioxidative activities. Addition of green tea or mugwort during cheongkookjang fermentation increased the antioxidative activity, cheongkookjang with green tea showed more drastic increase compared with cheongkookjang with mugwort. Nitrite scavenging effects of the cheongkookjang extracts were prominent but the addition of green tea or mugwort seldom increased the scavenging effects. All the cheongkookjang extracts showed strong inhibitory activities on platelet aggregation. The inhibitory activities of cheongkookjang were increased considerably by addition of green tea or mugwort even with low concentration. Plasmin unit as fibrinolytic activity was not affected considerably by addition of green tea. Addition of mugwort decreased the activity transiently at low concentration ($0.3{\sim}1.0%$) but increased again slowly at higher concentration ($1{\sim}3%$). In vitro thrombotic death inhibition test, the antithrombotic activity of cheongkookjang made of black small bean with green tea was higher by about 1.5 times compared to that without green tea. As results, cheongkookjang might inhibit antithrombosis not only by fibrinolytic action but also by inhibition of platelet aggregation and antioxidative action. The addition of functional materials such as green tea or mugwort could increase the antithrombotic function, even at low concentration.

Rheological Properties of Korean Wheat Composite Flour and Dough with Nelumbo nucifera G. Tea Powder (백련차 분말을 대체한 우리밀 혼합분과 반죽의 특성)

  • Kim, Young-Sook;Jung, Seung-Tai;Kim, Mun-Yong;Chun, Soon-Sil
    • Korean journal of food and cookery science
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    • v.24 no.6
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    • pp.757-762
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    • 2008
  • In this study, korean wheat composite flour and dough were prepared with 1.5, 3.0, 4.5, and 6% Nelumbo nucifera G. tea powder(NNTP). The samples and a control were then compared qualitatively in terms of moisture, protein, ash, and wet gluten content. The farinogram, amylogram, and extensogram characteristics of the dough were also examined, in order to determine the optimal ratio of NNTP for the formulation. According to our results, the moisture content of the flour decreased with increasing NSPP content, whereas its protein and ash content, resistance, and R/E ratio at 135 min of extensogram increased. The NNTP samples had a significantly higher water absorption and weakness of farinogram and maximum resistance at 45, 90, and 135 min. Additionally, samples had an R/E ratio at 45 min of extensogram, 90 min less than the control group. However, stability of the farinogram, temperature of maximum and maximum viscosity of the amylogram, and extensibility of the extensogram showed the reverse effect. The control and NNTP samples showed significant differences in gelatinization beginning temperature of the amylogram, while development time of the farinogram was not significantly different. With regard to the extensogram characteristics of the dough, the area of the control and 1.5% NNTP increased with increasing testing time, whereas at 3.0, 4.5 and 6.0% NNTP, extensibility, and resistance, maximum resistance, and R/E ratio of control and NNTP samples decreased. An area of 3.0, 4.5 and 6.0% NNTP and extensibility of 1.5% NNTP were not significantly different among the testing times. In conclusion, these results show that 1.5% NNTP may prove very useful as a substitute for korean wheat flour where the production of korean wheat white bread is concerned. It may also provide good nutritional and functional properties.

Studies on the Extraction of Korean Ginseng Component -Part 1. Differences of Saponins in Korean Ginseng by Cultivation Area and Processing- (인삼성분(人蔘成分)의 추출(抽出)에 관한 연구 -제1보 인삼(人蔘)의 지역별(地域別) 및 가공중(加工中) Saponin구성성분(構成成分)의 변화-)

  • Yu, Ju-Hyun;Kim, Hai-Jung;Pyun, Yu-Ryang;Nam, Sung-Hi
    • Korean Journal of Food Science and Technology
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    • v.9 no.4
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    • pp.313-316
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    • 1977
  • The patterns of saponins of lateral gingengs cultivated different areas and various ginseng products were investigated by quantitative thin-layer chromatography. In the case of ginseng cultivated in the Kum San and Gang Hwa area, some parts of the panaxatriol series of the saponins (peak 6 and 7.8.9) were higher in concentration than in ginseng grown in other areas while the other ingredients were almost the same. In the process of heat treatment the quantity of peak 2 was generally decreased. However, in the case of red and white ginseng, one part of the panaxatriol saponins, peak 6 was increased. This tendency was also found in honeyed ginseng and ginseng tea which were not exposed to sunlight, but the increase was much less. The change in the red and white ginseng which were exposed to sunlight was very substantial. Therefore we can assume that the increase of peak 6 comes about due to the combination of heat treatment and exposure to sunlight, especially due to exposure to sunlight.

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