• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.7
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• pp.980-986
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• 2005

This study was carried out to investigate the effect of diet (1:1 ratio) added with meat product (seasoning chicken product, patty) containing natural extracts (green tea, Schizandra chinensis) on body weights, internal organs weights, the contents of total cholesterol, HDL-cholesterol, triglyceride and total lipid in plasma and liver. The experimental diets were prepared with basal diet added with $1\%$ natural extracts. These diets were supplied to SD (Sprague-Dawley) rats for 45 days. The body weight of SD rats supplied seasoning chicken and patty containing green tea and Schizandra chinensis tended to be lower than that of SD rats dieted seasoning chicken product and patty product. The contents of plasma cholesterol, HDL-cholesterol, triglyceride and total lipid were decreased in SD rats dieted seasoning chicken and patty with green tea and Schizandra chinensis. However, the contents of plasma cholesterol, HDL-cholesterol, triglyceride and total lipid tended to be increased in SD rats supplied seasoning chicken product and patty only. Hepatic lipid peroxidation measured by TBARS method was not different, compared to that of control. In conclusion, the diets with meat products containing $1\%$ natural extracts were effective in reducing plasma and hepatic cholesterol levels in rats.

• The Korean Journal of Community Living Science
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• v.22 no.3
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• pp.327-339
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• 2011

This study aims to investigate relationships between benefit sought and selection attributes of green tea consumers. For data collection, a total of 595 copies of questionnaires were collected by convenience sampling in the Seoul and Gyeonggi-do area. The data were analyzed by using SPSS 15.0. The factor analysis identified four dimensions of the benefit sought : health benefit, sensory, sociality, and self-esteem. Six dimensions of selection attributes were identified as manufacturing, design, sensory appeal, recommendation, utility and brand. The results of the canonical correlation analysis indicated that health benefit, sensory, sociality of benefit sought and manufacturing, design, sensory appeal, recommendation, utility, brand of selection attributes were highly correlated, and the self-esteem of benefit sought and recommendation of selection attribute were highly correlated. This means it is important to place an emphasis on safety production, package design, sensory characteristics, product description, utility and brand for consumers who seek health benefit, flavor and sociality. It is also important to place an emphasis on product description for consumers who pursue self-esteem benefits. Green tea marketers should consider benefit sought aspects as the most important factors affecting selection attributes on green tea purchasing.

• Food Science and Industry
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• v.52 no.1
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• pp.11-19
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• 2019

Various sensory technologies have been used at different stages of product development. In this paper, the examples of sensory studies in teas and cosmetics were shown, and these could help to increase the contribution of sensory sciences to the development of products in the industry. In classical approach, descriptive analysis with trained panel and consumer acceptability test are very important to identify the sensorycharacteristicsthatdriveconsumeracceptability of products. Recently, some quick and easy sensory evaluation methods were introduced such as CATA (check-all-that-apply), sorting, and $Napping^{(R)}$, etc. to gather information about consumers' perception of the sensory characteristics of products. Although there are many sensory methodologies available in the product development phase, the most important thing is that these have to be correctly selected and designed for target consumers, products, and research purposes in order to develop a successful product.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.4
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• pp.295-299
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• 2004

The prices of domestic green tea products are relatively expensive and price differences within products of the same levels of quality are various. Also, there is no basic criteria on evaluation of green tea quality. To group 43 commercial green tea products into several parts by the principal component and cluster analyses, this work was done by use of 8 chemical constituents which were analyzed by NIR system. The principal component and cluster analyses revealed 8 groups. The first group included 16 products that had lower free amino acid and theanine contents. The second group included 5 products having higher free amino acid and theanine contents, but lower ash contents. The third group included 13 products showing medium values of 8 constituents. The IV group included 4 products having higher contents of moisture, free amino acids, and theanine. The V group included 1 product showing higher moisture but lower catechins contents. The VI group included 2 products that had higher moisture and catechins contents, but lower free amino acid and theanine contents. The VII group had higher moisture and catechins contents. The VIII group had higher ash and vitamin C contents. The free amino acid contents which were the most important in flavor evaluation of green tea quality did highly positively correlate with the contents of total nitrogen $(0.956^{**}),\;theanine\;(0.981^{**}),\;and\;caffeine\;(0.793^{**})$, but negatively with the contents of ash $(-0.884^{**})$. The catechins used as for functional ingredients did correlate with contents of caffeine(+) and vitamin C(-), respectively.

• Natural Product Sciences
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• v.19 no.4
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• pp.281-285
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• 2013

This study was designed to investigate the nervous sedative effects of green tea. The sedative effect was evaluated by examination of Monoamine oxidases (MAOs) inhibitory activity in vitro in the brain and liver of rat fed on green tea cultivated and harvested from the different regions and periods. It showed that methanol extracts of green tea inhibited significantly the brain MAO-A activity. Especially late harvested green tea extracts showed potential inhibitory activity. The liver MAO-B activity was also inhibited by all of the green tea extracts with strong intensity. This study confirmed that major compounds of green tea such as catechin, epigallocatechin-3-gallate (EGCG) and L-theanine, which were well known for the main bioactive components in the tea plants, were not associated with the MAO inhibitory activities of green tea. These results suggested that a MAO inhibition activity comes from other minor tea components we have to search in the future.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.3
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• pp.399-405
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• 2010

After Gomchui tea was prepared from leaves of Ligularia fischeri (Ledeb.) Turcz by blanching method, the antioxidant activity of major compounds in Gomchui tea was assessed. On-line HPLC-ABTS analysis revealed that caffeoylquinic acids (chlorogenic acids), such as 5-O-caffeoylquinic acid (5-CQA), 3,4-di-O-caffeoylquinic acid (3,4-DCQA), 3,5-di-O-caffeoylquinic acid (3,5-DCQA) and 4,5-di-O-caffeoylquinic acid (4,5-DCQA), were the major antioxidant compounds in Gomchui tea. The extraction efficiency of these compounds were examined in the various conditions such as extraction temperature, time and solvent. The results demonstrated that the extraction amount with water increased in proportion to extraction time (1~10 min) and temperature ($8{\sim}80^{\circ}C$). These active compounds were also extracted with water even at $8^{\circ}C$ (60% of $80^{\circ}C$), indicating that water is very good extraction solvent for extraction of these antioxidant constituents. However, the extraction efficiency of these compounds decreased when ethanol percentage in water increased. The extraction efficiency between Gomchui powder (no blanching) and tea was significantly different, and 60% of total antioxidant compounds in tea was removed from fresh leaves into water in blanching process, especially 3,5-DCQA (over 90%). Meanwhile, the sonication method didn't affect the extraction of these compounds in all solvents. These results suggest that Gomchui tea can be a good candidate for the tea beneficial to human health.

• Korean Journal of Organic Agriculture
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• v.29 no.4
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• pp.613-623
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• 2021

This study was conducted to investigate the effect of addition levels of coffee and green tea by products extract including polyphenols through hot water extraction on rumen fermentation. The treatment groups consisted of coffee extract (CO), green tea extract (GR) and mixed extract (MIX), and the addition level was 10 µL, 20 µL and 30 µL of three levels. The experiment consisted of a total of 10 experimental groups including the control group, and a full factorial design was used. The effect of polyphenol addition in coffee and green tea by-products was analyzed through main and interaction effect of statistical analysis. The total polyphenol content of the extracts was 106.15, 79.10 and 185.25 ㎍ GAE/g DM for coffee by-product, green tea by-product and mixture, respectively. Total gas production was significantly lower in the treatment groups than in the control (114.00 mL/gDM) (p<0.05). Methane emission tended to decrease as the polyphenol addition level increased. Moreover, the MIX showed the lowest methane emission when 30 µL was added (p<0.05). Volatile fatty acids showed a significant difference compared to the treatment group as a control (98.06 mM) (p<0.05), but there was no change according to the level of polyphenols. As a result of the main effect and interaction, it is thought that the effect on methane reduction and improvement of rumen fermentation in MIX20 can be expected. In a series of studies, the addition of 20 µL of a blended extract of coffee and green tea by-products is thought to reduce methane to levels that do not inhibit rumen fermentation.

• Natural Product Sciences
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• v.19 no.2
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• pp.166-172
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• 2013

Caffeine and epigallocatechin gallate (EGCG) are major constituents of green tea, the leaves of Camellia sinensis (Theaceae). Although EGCG is well known for diverse beneficial effect, caffeine is sometimes harmful with adverse effects. Therefore, the extraction efficiency was investigated using different extraction method such as extraction solvent, extraction time, extraction method, and repeated extraction. The content of EGCG and caffeine in green tea extract was quantitated by HPLC analysis. The extraction condition exerted difference on the extraction yield. The content of EGCG was also affected by different extraction condition. Especially, the extraction solvent greatly affected the content of EGCG in the extract. However, the content of caffeine was less affected compared to that of EGCG. The inhibitory effect of green tea extract on pancreatic lipase was almost similar regardless of extraction condition. Taken together, optimization of extraction condition will provide best efficacy for further development of green tea as anti-obesity therapeutics.

• Journal of the Korean association of regional geographers
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• v.12 no.2
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• pp.229-244
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• 2006

Geographical indications are signs which identify a good as originating in the territory of a specific country, region, or locality, where the quality, reputation or other characteristics of the product is essentially attributable to its geographical origin. Korea has implemented geographical indication system through its Agricultural Product Quality Control Act since 1999. This research analyzes the impacts and implications of geographical indications on a particular cultural industry in a region using a case study of Boseong green tea which is the first product that was officially registered as a geographical indication in Korea. The results show that the geographical indication has contributed to the promotion of green tea industry in Boseong not only through increase of production but also through development of tourism. The implication is that a geographical indication can be used as an effective method to cope with trade liberalization in terms of agricultural policy. Another implication is that a geographical indication provides an efficient tool for place marketing.

• The Korean Journal of Food And Nutrition
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• v.37 no.2
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• pp.100-109
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• 2024

This study examined the quality characteristics and antioxidant properties of sword bean tea available in domestic markets. Each product of sword bean tea had distinct appearance characteristics. The color, pH, brownness, and turbidity of the tea varied significantly across different products, with tea bags showing higher levels of brownness and turbidity. The total polyphenol content of hot water extraction ranged from 165.13 to 517.69 mg gallic acid equivalents (GAE)/100 g sample for pod tea, 999.36 to 2,054.74 mg GAE/100 g sample for tea bag tea, and 74.62 to 275.00 mg GAE/100 g sample for grain tea, respectively. Similarly, the total flavonoid content, measured in terms of catechin equivalents (CE), ranged from 39.51 to 65.00 mg CE/100 g sample for pod tea, 86.57 to 253.63 mg CE/100 g sample for tea bag tea, and 32.94 to 38.63 mg CE/100 g sample for grain tea, for hot water extraction. The DPPH and ABTS radical scavenging activities of pod tea were 95.68 to 276.19 mg TE/100 g sample and 270.87 to 804.21 mg trolox equivalents/100 g sample, respectively, for hot water extraction. These results suggest the need to establish quality standards to ensure consistent quality of sword bean tea.