• Korean journal of food and cookery science
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• v.18 no.2
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• pp.129-135
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• 2002

The effects of adding green tea powder on the quality and storage characteristics of tofu were studied. As the addition of green tea powder increased, the moisture content of tofu was decreased but those of crude protein and the crude ash were increased. The addition of green tea powder increased the production of whey and consequently decreased the yield of tofu. At the beginning of storage, the pH of the tofu with green tea powder was increased, but decreased rapidly at the eighth day of storage. The pH of tofu-soaking solution was decreased during the storage period. The L and b values showed no significant changes but a value was increased during storage. Textural characteristics of tofu added with green tea powder also did not show significant changes during storage. Although the total plate counts and absorbances of soaking solution of tofu were increased during storage, the samples with 1.0% green tea powder had the lowest TPC (3.0$\times$10$\^$6/ CFU/ml) and the lowest absorbance (0.175) at the eighth day of storage.

• Journal of Nutrition and Health
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• v.41 no.7
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• pp.602-611
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• 2008

We compared antiobese, hypocholesterolemic, antiplatelet and antioxidant effect of 10% green tea powder and 3% green tea extract in rats pair fed 5% cholesterol diets. The final body weight was decreased significantly compared with the control (p < 0.05). Plasma and liver total cholesterol were lower in group of green tea powder or extract, but not statistically different. HDL cholesterol was increased significantly in group of green tea powder compared with the control or green tea extract (p < 0.05). Plasma triglyceride was significantly decreased in group of green tea extract compared with green tea powder, and green tea powder compared with the control respectively (p < 0.05). Liver triglyceride was significantly decreased in group of green tea powder or green tea extract compared with the control (p < 0.01). Platelet aggregations in the maximum and initial slope were not different among groups. Hemolysis was significantly lower in group of green tea powder compared with the control (p < 0.05). Plasma TBARS production was decreased in group of green tea extract compared with the control (p < 0.05). Na passive leak in intact cells was not different, but Na leak in AAPH treated cell was significantly decreased in group of green tea powder than the control (p < 0.05). The leak increase (${\Delta}Na$ Leak) after AAPH treatment was significantly decreased in groups of green tea powder and extract compared with the control (p < 0.05). Isotope excretion after $^{14}C$-cholesterol ingestion was significantly increased in group of green tea extract compared with the control or the green tea powder (p < 0.05). Consumption of green tea in powder or extract may give beneficial effects in weight control and plasma lipid profiles, impeding metabolic syndrome. More studies are needed to clarify what component of green tea and what mechanism are involved in antiobese and hypolipedemic actions of green tea.

• Journal of the Korean Society of Food Culture
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• v.22 no.5
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• pp.609-614
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• 2007

Quality characteristics of dasik were studied with varied the levels of rice grain particle size and green tea powder and compared them with commercially sold dasik. Among the samples with the same number of grinding times, the sample groups with the higher amount of green tea showed significantly the less mosture content(p<0.05). Hardness was higher in the samples containing higher amount of green tea among the ones with the same grain size (p<0.05). The M13G0.5 was evaluated to have the highest savory aroma with significance (p<0.05), and C1 to have the highest sweetness by sensory analysis. The developed dasik samples with lower rice grain particle size had significantly lower adhesiveness, chewiness, gumminess, and cohesiveness compared to those of commercial sample groups. In sensory tests, the compared groups showed significantly the higher savory aroma and flavor and very lower hardness when compared to those of commercial sample groups. With the results above, dasik with with varied the levels of rice grain particle size and green tea powder were developed with improved qualities compared to those of commercially sold dasik.

• Journal of the East Asian Society of Dietary Life
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• v.23 no.6
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• pp.713-722
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• 2013

The purpose of this study was to examine the effects of dietary green tea powder supplementation on bone metabolism in streptozotocin-induced diabetic rats. Thirty-two male Sprague-Dawley rats (body weight $210{\pm}3g$) were divided into two groups, diabetic and non-diabetic groups. Each group was randomly divided into two subgroups which were fed with the control and 1% green tea powder diets. The serum and urine concentrations of calcium and phosphorus were determined. Serum osteocalcin and ALP and urinary DPD crosslinks value were measured in order to monitor bone formation and resorption. Bone mineral density (BMD) and bone mineral content (BMC) were estimated using PIXImus in the spine and femur. Body weight gain and FER were lower in the diabetic group than in the non-diabetic group regardless of diets. The serum concentration of calcium and phosphorus were not changed among all groups. Urinary calcium and phosphorus excretion were higher in the diabetic group than in the non-diabetic group regardless of diets; however, they were not significantly different by green tea powder intake. Serum alkaline phosphatase (ALP) was increased in the diabetic group than in thenon-diabetic group. Further, there were no significant differences in serum osteocalcin and urinary deoxypyridinoline crosslinks value among all groups. The levels of spine and femur bone mineral density of the diabetic group were significantly lower than that of the non-diabetic group. Within the diabetic group, spine BMD was significantly higher in rats fed with the green tea powder diet than in rats fed the control diet. Therefore, this study suggests that green tea powder has a beneficial effect on bone health, although it is not directly applicable to humans.

• 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.

• Journal of Nutrition and Health
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• v.34 no.5
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• pp.525-531
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• 2001

The present study investigated the protective effects of green tea against acute ethanol-induced lipid peroxidation and the change of antioxidative enzyme activities in various regions of rat brain : cortex, cerebellum, striatum and hippocampus. The following parameters were examined : malondialdehyde(MDA) levels and activities of superoxide dismutase(SOD), catalase and glutathione peroxidase(GSH-Px). Male Sprague-Dawley rats were given the experimental containing 1% green tea powder or control diet for 4 weeks, and at the end of feeding diet group received acute ethanol(5g/kg body weight) or equicaloric sucrose solution intragastrically. Green tea powder significantly decreased MDA levels in the striatum compared to control-non alcohol treated group to 1% green tea-non alcohol treated group without altering the antioxidative enzyme activities. Green tea resulted in a significant increase in GSH-Px activities in the hippocampus compared to either control-non alcohol treated group(0.043units/mg protein) or 1% green tea-non alcohol treated group(0.071units/mg protein). In conclusion, these results suggest that moderate consumption of green tea leaves can exert protective effects against ethanol-induced oxidative stress in brain regions, by reducing MDA concentrations in the striatum and enhancing GSH-Px activities in the hippocampus. (Korean J Nutrition 34(5) : 525∼531, 2001)

• Food Science of Animal Resources
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• v.25 no.4
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• pp.500-506
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• 2005

This study was carried out to obtain knowledges on the survival of Streptococcus mutans in the yoghurt added with green tea powder. The growth inhibition of green tea powder on the food borne pathogens and oral bacteria was measured by total microbial count, Among the tested food borne pathogens, the growth of Staphylococcus aureus and Salmonella enteritidis were not significantly affected by the addition of green tea powder, but green tea powder showed the growth inhibition effect on Escherichia coli O157:H7. The number of surviving Streptococcus mutans cell was decreased by $0.56\~0.99log$ cycle after 24 hem incubation by the addition of $0.5\~2.5\%$ green tea powder in the medium. And also the viable cell count of surviving Streptococcus mutans cells (initial inoculum $3.4\times10^7CFU/mL$) were decreased to $1.4\times10^4\~7.2\times10^4 CFU/mL$ after 48 hours incubation when $0.5\~2.5\%$ green tea powder were added to the drinkable yoghurt, Growth of Streptococcus mutans was strongly inhibited by the addition and incubation of green tea powder for 48 hum in the yoghurt.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.2
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• pp.230-235
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• 2002

The purpose of this study was to investigate the characteristics of beef jerky adding of many kinds of saccharides and three levels of green tea powder. Color and hardness were increased with the addition of green tea powder while tenderness was decreased. Moistureness Gf beef jerky added honey was higher than that of sugar, oligo saccharide. In color, the lightness was decreased with increasing concentrations of green tea Powder. Redness and yellowness values were increased. In measurement of texture, hardness were increased with the addition of green tea powder. The hardness of beef jerky by adding of honey appeared to be higher than that of sugar, oligo saccharide. Gumminess and brittleness were increased with the addition of green tea powder while springness was decreased. Springness in addition of 3% green tea powder was higher than control. The beef jerky added with 3% green tea powder and sugar had good overall perference.

• The Korean Journal of Food And Nutrition
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• v.18 no.4
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• pp.325-333
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• 2005

This experiment was carried out to investigate the effect of green tea powder on the growth and acid production of lactic culture in reconstituted skim milk. The supplementation level of green tea powder to reconstituted skim milk was $0.5\%,\;1.0\%,\;1.5\%,\;2.0\%\;and\;2.5\%$. Reconstituted skim milk containing green tea powder was fermented by single or mixed culture of Streptococcus thermophilus, Lactobacillus acidophilus and Lactobacillus casei. Supplementation of green tea powder did not significantly stimulate growth and acid production of Streptococcus thermophilus and Lactobacillus casei. But the growth and acid production of Lactobacillus acidophilus were slightly enhanced by the addition of green tea powder. When green tea powder was added to reconstituted skim milk at the level of $0.5\%\;or\;1.0\%$, all mixed cultures oi lactic acid bacteria showed high number of viable cell count and the acid production than 3 kinds of single cultures. Therefore, it was suggested to manufacture the yoghurt with the addition of $0.5\~1.0\%$ green tea powder and the inoculation of mixed cultures of lactic acid bacteria for on the stimulation of growth of the lactic culture.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.6
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• pp.920-924
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• 2007

Two experiments were carried out on a laboratory scale. The first involved a study of the effect of green tea on characteristics of fermented juice of epiphytic lactic acid bacteria (FJLB). FJLB was treated with 50 g/L of green tea products as follows: new shoot powder (FJLB+N), leaf powder (FJLB+L), commercial powder (FJLB+P), sterilized new shoot powder (FJLB+SN), sterilized leaf powder (FJLB+SL) or sterilized commercial powder (FJLB+SP). FJLB without any additive was also prepared (Untreated FJLB). After incubation, the number of microorganisms in FJLB were studied. Subsequently, these FJLB were applied at 10 ml/kg to chopped rhodesgrass to study their effects on fermentation. Compared with untreated FJLB, the addition of green tea increased (p<0.05) lactic acid bacteria (LAB) and also aerobic bacteria counts in FJLB. At 60 d of ensiling, all the FJLB treated silages were well preserved, pH and butyric acid content were lower (p<0.001) and lactic acid was higher (p<0.001) than that of the control. Lactic acid content was significantly higher (p<0.001) with treated FJLB than with untreated FJLB. FJLB treated with sterilized green tea decreased (p<0.001) the pH and the lactic acid content was higher (p<0.001) than that in the unsterilized green tea silages.