• Korean Journal of Food Science and Technology
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• v.13 no.4
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• pp.267-272
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• 1981

The qualities of ginseng leaf teas prepared by six different processing methods were evaluated to develop the leaf tea. The leaf tea prepared by fermentation at $30^{\circ}C$ showed the highest in the ratio of 30 min water extracts to the total extractable matters. This ratio was followed in decreasing order by the heat dried tea and the one fermented at $25^{\circ}C$. The yellow, orange and red color intensities of water extracts were the highest in the tea prepared by toasting method followed by teas fermented at $30^{\circ}C\:and\:25^{\circ}C$. The amount of saponins extracted with boiling water was the highest in the tea fermented at $30^{\circ}C$ among teas investigated. This tea was also most acceptable in sensory evaluation by the flavour profile method.

• Korean Journal of Food Science and Technology
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• v.9 no.1
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• pp.24-30
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• 1977

The patterns of ginseng saponins in the commercial ginseng tea samples and each parts of ginseng plant were investigated by quantitative thin-layer chromatography. The quality of those sample teas were also evaluated. (1) White ginseng contained about $2.6{\sim}6.6$ times of Ra(o) than did other parts of ginseng. (2) Lateral roots, peelings and buds of ginseng were rich in $Rb_1$, $b_2$, c, which constituted about 50% of total saponin. (3) The ratio of Rb.c to Rg(f) in the leaves and stems of ginseng plant was 0.64 : 1. (White ginseng, 2 : 1 ; buds, 3 : 1 ; flower, 3.2 : 1 ; peelings, 5.8 : 1 ; lateral ginseng, 7 : 1) The relative content of Rg(f) in the white ginseng was about 3 times as much as the lateral ginseng. (4) The ratios of panaxadiol to panaxatriol in 13 kinds of commercial ginseng teas were in the range of $0.8{\sim}8\;:\;1$.

• Journal of Food Hygiene and Safety
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• v.31 no.2
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• pp.132-139
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• 2016

The purpose of this study was to investigate the contents of antioxidant compounds and antioxidant activities in teas. A total of 99 teas were tested for their antioxidant activities based on their ability to scavenge DPPH (1,1-diphenyl-2-picrylhydrazyl) free radical. Antioxidant activity was expressed as mg of ascorbic acid equivalents per 100 g tea sample (L-ascorbic acid equivalent antioxidant capacity, AEAC) and was expressed as mg per 1 serving size (free radical scavenging activity, $FSC_{50}$). The total polyphenol contents of the extracts was quantified using the Folin-Ciocalteu method and the total flavonoid contents of the extracts was determined using a modied method of Davis. Vitamin C was analyzed by HPLC method. According to the AEAC value, mate tea, green tea, black tea, oriental raisin tea, chamomile tea and burdock tea showed relatively high antioxidant activities. Polyphenolic compounds were the major naturally occurring antioxidant compounds found in teas and the high concentrations of total polyphenol compounds were observed in black tea, green tea and mate tea. The high concentrations of total flavonoid compounds were observed in mate tea, black tea and yam tea and the amount of vitamin C contents were found to be high in citron tea and green tea. As a result, steeping tea was much higher in antioxidant activity than either powdered tea or liquefied tea. According to the study, a high correlation was demonstrated between the total polyphenol contents and antioxidant activities in teas (r = 0.846) and correlations between the total flavonoid contents and antioxidant activities was statistically significant in teas (r = 0.625). It was found that also the proportional relationship established among the total polyphenol content and antioxidant activities. That is, antioxidant activity of teas has been confirmed to have been caused by the total polyphenol.

• Korean Journal of Food Science and Technology
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• v.31 no.5
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• pp.1144-1152
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• 1999

In order to investigate the content of preservative components occurred naturally in foods, the content of benzoic acid and sorbic acid in 48 kinds of plants which used as commercial teas or spices was determined according to the method of 'Korean Food Code' and analyzed with a gas chromatograph. The recoveries of the benzoic and sorbic acid were 82.5% and 94.5%, respectively. The naturally occurring benzoic acid was less than 50 ppm in most of the plants used as commercial teas. The content of benzoic arid in spices and the content of sorbic acid in teas or spices were less than 10 ppm. The average contents of benzoic acid and sorbic acid in edible part of each plant were as followed ; leaf 12.5 ppm and 8.1 ppm, root 16.8 ppm and 3.7 ppm, seed 9.8 ppm and 2.3 ppm, fruit 33.8 ppm and 1.2 ppm, fungus 18.3 ppm and 14.6 ppm, respectively. The contents of benzoic acid and sorbic acid in several plants used at teas or spices extended over a wide range.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.3
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• pp.645-653
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• 2011

The aim of this study was to develop a Pulsed Magnetic Fields(PMFs) system which can produce effects locally and simulate muscular tissues equally. To evaluate the PMFs system we caused DOMS(Delayed Onset Muscle Soreness) to subjects in biceps of the arm. Then, we stimulated acupoint HT2 using PMFs(20 minutes) and TEAS(20 minutes) for 2 days. The other subjects did not stimulate. Then we checked body surface temperature in biceps of the arm. All subjects had an asymmetrical body surface temperature in biceps after exercise(Non-stimulation group=$2.00{\pm}1.16^{\circ}C$, TEAS group=$1.73{\pm}0.52^{\circ}C$, PMFs group=$1.48{\pm}0.51^{\circ}C$). After 1st stimulation all subjects had decreased temperature differences(Non-stimulation group=$1.37{\pm}0.71^{\circ}C$, TEAS group=$1.08{\pm}0.43^{\circ}C$, PMFs group=$1.23{\pm}0.15^{\circ}C$). PMFs group had a symmetry body surface temperature after 24 hours($0.05{\pm}0.06^{\circ}C$) and TEAS group had that after 48 hours($0.1{\pm}0.08^{\circ}C$). Non-stimulation group did not recovery after 48 hours($0.37{\pm}0.06^{\circ}C$). Therefore, PMFs on acupoint had an therapeutic effect in DOMS.

• Journal of the Korean Applied Science and Technology
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• v.36 no.1
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• pp.1-12
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• 2019

After making tea by steaming the Artichoke(Hellanthus tuberosus) nine times and drying them nine times, the ingredients and functions of the Artichoke tea were compared to those of M. It had 342.27kcal/100g in its own deloped Artichoke tea, 73.87g/100g of carbohydrates, 6.80g/100g of crude ash and 8.21g/100g of crude protein. The total of free sugars were 32.66mg/100, among them, fructose 17.40, sucrose 9.03 and glucose 6.05 mg/100g. The total mineral contents of the developed tea was 2,785.67mg/100g. It was 2,563.93mg/100g of potassium, 97.52mg/100g of calcium and 88.78mg/100g of magnesium. The saturated fat of Artichoke tea was 30.34mg/100g and unsaturated fat was 69.66mg/100g, among which the linoleic acid was 47.0mg/100%, palmitic acid was 25.31mg/100% and linolenic acid was 8.61mg/100g. DPPH radical scavenging was 34.2% of teas that were developed, 5.2% of M's for comparison, and 44.0% of index materials. ABTS radical scavenging was 93.0% of teas developed, 61.9% of M's tea and 47.6% of index materials, and SOD like activity was 2.7% of teas developed and 1.6% of M's tea. The flavonoid content was 2.8 fold of the tea developed, 2.0 fold of M's tea and 1.7 fold of index material. The polyphenol content was 38.2 fold, 8.92 fold of M's tea and 14.0 fold of index material. The inhibition rate for ${\alpha}$-glucosidase was 9.83% teas developed and 8.92% of M's. The sensory evaluation compares to the one time extract and the five time extract. Based on the one-time extract, color of tea developed was 83.7%, the M's tea was 50.0%, the flavor was 78%, M's tea was 42.5%, the delicate taste was 66.7% of teas developed and M's tea was 37.5% and the overall acceptability was 73.3% of teas developed, M's tea was 47.5%. The comparison of M's tea showed that the extract decreased as we made it, and the overall symbol level decreased to 46.3% after five time-extyracts, while that of the developed tea decreased to 73.3%. The Artichoke tea developed this way is believed to have greater antioxidant function, higher effective substance content, and a higher affinity than M's tea an index material for comparison purposes.

• Current Research on Agriculture and Life Sciences
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• v.28
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• pp.1-7
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• 2010

The antioxidant activities and flavonoid contents of the mulberry leaves and the ginko leaves teas were investigated. The antioxidant activities were examined by FRAP and DPPH radical scavenging assays, and total phenolic content and the flavonoid contents by HPLC were also determined. The ginko leaves tea showed the highest antioxidant activities and antioxidant contents, while the wild mulberry leaves tea showed the lowest. The antioxidant activities of the mixture tea of wild mulberry leaves and ginko leaves were increased more than the wild mulberry leaves tea. The flavonoid contents of the leaves(ginko, wild mulberry and mixture) powders were higher than those of infusion teas. Compared with wild mulberry tea, the mixture tea showed a little increase of flavonoid contents. The total phenolic contents and the flavonoid contents of the teas showed good correlations with their antioxidant activities, such as FRAP and DPPH radical scavenging activities(${\geq}0.8727$). The antioxidant capacities of wild mulberry leaves tea could be enhanced by the addition of the ginko leaves.

• Journal of Food Hygiene and Safety
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• v.26 no.2
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• pp.100-106
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• 2011

This study was conducted to investigate the residue amount of harmful materials on the 113 commercial fruit teas (Gugija, Omija, Sansuyu) in Gwangju area. It was performed using the GC-ECD, GC-NPD, GC-MSD and the LC-UVD, LC-FLD, LC-MSD to analyze 200 pesticides. The heavy metals were determined using a Mercury analyzer and AAS. The sulfur dioxides were analyzed by modified Monnier-Williams method. The residual pesticides were detected in 4 samples (Gugija). The mean values of heavy metal contents (mg/kg) were Pb, 0.024; Cd, 0.031; As, 0.010; Hg, 0.003. The measured values of Pb, Cd, As, Hg showed within MRLs. The sulfur dioxides were over MRLs in 4 samples (Gugija). These results will be used to establish on the regulation of commercial fruit teas in Gwangju area.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.5
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• pp.863-866
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• 1994

This study was carried out to estimate aluminum contents of commercial beverage foods by atomic absorption spectrophotometer. The contents of aluminium in drinking yogurt, curd yogurt, fruit beverage, carbonated beverage, fruit canned food and commerical teas ranged from 161.667 to 173.333ppm 139, 300 to 293, 925ppm, 1.481 to 7.130 ppm, 1.803 to 6.026ppm, 4.600 to 7.053ppm 194.437 to 846.056 ppm, respectively.

• 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.