• Korean journal of food and cookery science
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• v.26 no.5
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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.

• Journal of the East Asian Society of Dietary Life
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• v.10 no.5
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• pp.411-418
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• 2000

The purpose of this study was to investigate the sensory and mechanical characteristics of mayonnaise containing various levels of green tea powder The highest viscosity of mayonnaise was obtained at the green tea powder concentration of 0.5% The emulsion, stability was increased with the addition of green tea powder. In the sensory evaluation, overall acceptabilty appeared to be the highest when 0.1% of green tea powder was added. There was a significant difference between the samples (P<.05) In terms of change in color, the values of L, a, b, and ΔE decreased as the amount of green tea powder increased. In the measurement of the texture, the hardness of mayonnaise was highest in the control of green tea powder, and the springiness appeared to be higher in the mayonnaise with 0.1% of green tea powder. The odor acceptabilty in the sensory evaluation showed a negative correlation with the values of gumminess in the mechanical characteristics. The subjective parameters that affect overall quality on sensory evaluation were determined by, and they were odor acceptabilty, after taste, oily taste, sour odor. sweet taste. egg odor, color acceptabilty, and salty taste. These results showed that mayonnaise made with 0.1% green tea powder, salad oil 474.5ml. egg golk 85g, sugar l0g, salt 7g, and vinegar 23m1 with the addition of 0.6g green tea powder was the most effective compared with other treatments.

• Journal of the Korean Home Economics Association
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• v.34 no.3
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• pp.233-243
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• 1996

The purpose of this study was to investigate effect of the amounts of unpolished glutinous rice flour with green tea powder difference of adding method on the sensorty and objective characteristics of Heunmi-nokcha-injulmi which is KOREAN TRADITIONAL CAKE supplemented with green tea. The results were as follow: According to sensory evaluation of Heunmi-injulmi adding twice infused green tea powder, the acceptance was the bast in the hardness, moistness, chewiness, and overall quality when adding 6% green tea. The more the amount of two infused green tea power was increased, the more the hardness of Heunmi-injulmi was increased in the gextural profiles, whereas the cohesiveness, elasticity, and chewiness of those was decreased. The moisture content of Heunmi-injulmi adding infused green tea powder was ranged to 41-44%, and it was decreased as the amount of two infusedgreen tea powder be increased. The more the amount of adding green tea powder was increased, the more yellow and green color was changed darker and stronger. The Overall quality in the sensory measurement of Heunmi-injulmi adding two infused green tea powder had positive correlation with Adhesiveness in the measurement of food testing machine. Refer to this study with the advisable recipe for Heunmi-nokcha-injulmi as follow : Heunmi-nokcha-injulmi adding 282g(94%) unpolished glutinous rice flour and 18g (6%) two infused green tea powder.

• The Korean Journal of Food And Nutrition
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• v.17 no.3
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• pp.266-271
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• 2004

In this study, rice was cooked with 0%, 0.5%, 1.0% and 2.0% green tea powder content to improve functionality of cooked rice. The effects of green tea powder content on the physical, texture and sensory characteristics of cooked rice were examined. Moisture contents of cooked rice with green tea powder were decreased with increasing amounts of added green tea powder. Initial pasting temperature of rice powder was showed an increase with increasing amounts of added green tea powder, besides peak viscosity was decreased. The solubility and swelling power were decreased with increasing amounts of added green tea powder. The color of cooked rice was darkened gradually with the increasing amounts of added green tea powder, and showed the dark green. Sensory adhesiveness was gradually decreased with the increasing amounts of added green tea powder, and cohesiveness, gummness, chewiness and hardness were increased. Sensory glassiness, overcook, stickiness and hardness had lower score than control group, but sensory color, flavor and overall acceptability had higher score with addition of 1.0% and 2.0% green tea powder. Concludingly, in items of overall sensory, cooked rice with 1.0% green tea powder showed the best result.

• Environmental Mutagens and Carcinogens
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• v.25 no.2
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• pp.71-75
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• 2005

Green tea and their major constituents such as catechins are famous materials for their anti-oxidative and anti-carcinogenic activity, but many compounds with reducing power can promote the oxidation in their oxidized form or in the presence of metal ion. We investigated the pro-oxidative effect of the ethanol extract equivalent up to 30mg of dried weight of green tea leaves in four in vitro systems which could be used for detecting DNA damage. Although ethanol extract of green tea did not show significant mutagenicity in Salmonella typhimurium TA102, which is sensitive strain to oxidative stress, it degraded deoxyribose extensively in the presence of $FeCl_3-EDTA$ complex, promoted 8-oxoguanine formation in the live bacteria cell, Salmonella typhimurium TAI04, and cleaved super coiled DNA strand with the help of copper ion. It suggested that green tea, famous anti-oxidative material, can be pro-oxidant according to the condition of extraction or metal existence.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.7
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• pp.1021-1025
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• 2003

The study was to investigate the quality of wet noodle added with the powder green tea. The wet noodles were prepared to the ratio of 1, 2, 3, 5, 7.5 and 10% (w/w) of the powder green tea based on a flour weight. The initial pasting temperature in an amylograph was increased as the increase of the powder green tea, while peak and final viscosity as the increase decreased. The weight and volume of cooked noodles were decreased, and turbidity of soup was increased with the addition of the powder green tea. L and a values of wet noodles were decreased with the addition of the powder green tea, and b value was increased. Texture profile analysis of cooked noodle showed a increase of hardness, cohesiveness, springiness, chewiness up to 2% powder green tea, but decreased from 3% power green tea. However, adhesiveness decreased as the increase of the powder green tea. From the sensory evaluation, the wet noodles included 1% powder green tea were similarly evaluated as the noodle used whole wheat flour.

• Food Science and Preservation
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• v.16 no.3
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• pp.333-341
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• 2009

The antioxidant properties of green tea leaves and powder extracts were determined using several tests including estimation of reducing power, DPPH(1,1-diphenyl-2- picrylhydrazyl) radical-scavenging activity, and FRAP(Ferric reducing/antioxidant power) assay. All tests indicated that extracts of green tea powder had higher antioxidant activities than extracts of green tea leaves, and the activities were concentration-dependent. However, each test yielded somewhat different results with respect to storage conditions. The reducing power of green tea leaves was highest at $1,000{\mu}g/mL$, storage at $4^{\circ}C$, and an Aw(water activity) value of 0.23. However, the reducing power of green tea powder, assayed at $1,000{\mu}g/mL$, was high under all storage conditions(with variations in temperature and Aw), and was about 1.5.2-fold greater than that of green tea leaves. Radical-scavenging activity, as assessed by the DPPH assay, increased in a dose-dependent manner over the range $15{\sim}125{\mu}g/mL$. At higher concentrations, activities were $80{\sim}90%$ of maximal were attained. The FRAP activity of green tea extract also increased with rising concentration. Particularly in the case of green tea leaves, antioxidant activity was most greatest with storage at $-20^{\circ}C$ and Aw values of 0.69 and 0.23 when assayed at a concentration of $1,000{\mu}g/mL$. These results indicate that the most important factor during storage of green tea is not the Aw value but rather temperature, and that use of refrigeration($4^{\circ}C$) is preferable to increase or maintain the antioxidant activities of biological components in green tea.

• Korean Journal of Community Nutrition
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• v.13 no.2
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• pp.189-198
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• 2008

This study investigated the influences of the beverage intake on food behavior and personality for 1295 adolescents. The results were as follows. The favorite beverage was 'fruit juice', and preference of 'coffee' was the lowest. 'Milk and dairy product' was highest and 'milkshake' was lowest in intake frequency of beverage. The preference correlated positively(r = 0.391) with the intake frequency of beverage, especially high in 'green tea and black tea'(r = 0.622), 'coffee'(r = 0.581), 'carbonated drink'(r = 0.538), and 'milk and dairy product'(r = 0.501). The explanation power(R2) of beverage preference on beverage intake was 0.153. The explanation power($R^2$) of beverage intake on food behavior was 0.127, and 'carbonated drink' and 'coffee' as well as 'milkshake' had a negative influence on food behavior: however, 'milk and dairy product', 'green tea and black tea', and 'fruit juice' had a positive influence on food behavior. The relationship of beverage intake and sociality was very low($R^2$= 0.013), and 'isotonic drink' and 'green tea and black tea' had a positive influence on sociality. The relationship between beverage intake and anger expression was also very low. 'Coffee' showed a positive relationship with anger-in. 'Carbonated drink' and 'milkshake' showed a positive result with anger-out. 'Milkshake' showed a negative relation with anger-control, but 'green tea and black tea' and 'milk and dairy product' showed a positive relation. From these results, it was necessary to develop the practical nutritioneducation program on proper beverage choice for adolescents leading to better metal and physical status.

• Korean Journal of Microbiology
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• v.53 no.2
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• pp.103-117
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• 2017

The aim of this study was to evaluate the effect of green tea extract on probiotic potential, physico-chemical and functional properties of yogurt fermented with Lactobacillus acidophilus D11 or Lactobacillus fermentum D37 strains isolated from Doenjang. Probiotic activities such as the resistance to artificial digestive juices and the ability to adhere to epithelial cells were slightly higher in yogurt supplemented with green tea extract than in plain yogurt, which may be attributed to the increase in the number of lactic acid bacteria (LAB) by green tea extract supplementation. Furthermore, the microbiological and physico-chemical properties such as the number of LAB, organic acid production and viscosity were significantly (P<0.05) increased in yogurt added green tea extract compared to plain yogurt fermented with L. acidophilus D11. However, the green tea extract did not significantly (P>0.05) affect these properties of yogurt fermented with L. fermentum D37 strain. Meanwhile, the antibacterial activities against Escherichia coli O157 ATCC 43889, Salmonella enteritidis ATCC 13076, and Salmonella typhimurium KCTC 2514 and antioxidant activities including total phenol content, radical scavenging ability, and ferric-reducing antioxidant power were significantly higher in plain yogurt fermented with L. fermentum D37 than with L. acidophilus D11. The antibacterial and antioxidant activities of the yogurt were significantly (P<0.05) increased in proportion to the concentration of green tea extract added to plain yogurt. Consequently, green tea yogurt fermented with L. acidophilus D11 or L. fermentum D37 was considered to be a useful functional food that can inhibit the growth of pathogenic bacteria and scavenge the free radicals from the body cells.

• Journal of Applied Biological Chemistry
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• v.55 no.1
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• pp.19-25
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• 2012

Green tea leaves were fermented for 15 and 30 days with Monascus pilosus which is known to produce functional statins (TMs), and the content of various biochemical constituents such as total polyphenol (TP), total flavonoid (TF), theaflavin, and thearubigin were analyzed and compared with that of non-fermented green tea (GT) and Pu-erh Chinese post-fermented tea (PU). In addition to the electron donating ability (EDA), ferric iron reducing power (FIRP), xanthine oxidase (XO) inhibitory activity, superoxide dismutase (SOD)-like activity, iron chelating activity (ICA) and hydrogen peroxide contents were also measured and compared with that of GT and PU. Content of TP and TF in the water and ethanol extracts in TMs were lower than those in GT and PU. Theaflavin and thearubigin contents of water and ethanol extracts in TMs were higher than those of GT. And, these components were increased depending on the period of fermentation. While, EDA and FIRP of TMs were lower than those of GT, XO inhibitory activity of TMs was higher than non-fermented tea. While, ICA of TMs was slightly higher than GT and PU, the content of hydrogen peroxide in TMs was markedly lower than GT. This results suggested that the green tea fermented by M. pilosus was valuable for oxidative stress-induced diseases by decreasing hydrogen peroxide, and forming theaflavins and thearubigins with functionality of genus Monascus.