• Food Science and Biotechnology
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• v.18 no.5
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• pp.1212-1217
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• 2009

This study examined the influence of manufacturing processes and extraction conditions on the chemical compositions of green tea. Green tea samples grown in various areas (Korea, China, and Japan) and processed by 4 different methods (steaming, pan-firing, steaming and pan-firing, and heavy roasting after steaming and pan-firing) were collected for study. The chemical compositions of the green tea extracts and infusions were different according to their processing methods and extraction conditions, including catechins, caffeine, and free amino acids contents. In all samples analyzed, (-)-epigallocatechin gallate (EGCG), (-)-epigallocatechin (EGC), and theanine were determined as the major catechins and free amino acid, respectively. Studies of samples grown in the same area (Jeju; Korea) showed that there were significant differences in the concentrations of catechins and caffeine in extract and infusion according to the processing methods. These results indicate that processing methods influenced the chemical compositions of the green tea extracts and infusions.

• Journal of Applied Biological Chemistry
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• v.53 no.2
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• pp.116-119
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• 2010

A Maengjong-juk (Phyllostachys pubescence) leaves tea was prepared by using a series of drying/roasting and rolling processes. The produced tea contained abundant dietary fibers (60.42%), $\beta$-carotenes (7.9 mg RE%), and calcium (437.1 mg%). Also the polyphenol content ($155.33\;{\mu}g/g$-tea) and DPPH free radical scavenging activity ($IC_{50}=212\;{\mu}g/mL$) of Maengjong-juk leaves tea were greatly higher than those of simply dried leaves. These results imply that the tea preparation is effective to utilize the useful components of Maengjong-juk leaves.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.257-257
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• 2017

Being producing and evaluating oat-chocolate were a major goal in this study. There were various steps to make oat-chocolate. First, oat was roasted with an optimum roasting-temperature. Second, discovered the best natural antioxidant to extend storage period and improve quality of goods. Third, developed processing goods and made an evaluation of quality properties. We selected optimum roasting condition of $160^{\circ}C$ for 15 min based on the acid value and the sensory characteristics such as color, taste, smell and overall preference of oat flour. As for natural antioxidants, we made use of 3 kinds of antioxidants (cactus, lavender and green tea) and two concentrations (0.5 and 1%). In investigating antioxidants, an acid value was significantly decreased as the antioxidants were added (p<0.05). Nothing was as low in acid value as a chocolate with 1 % lavender flour in 7 days. Findings showed the sensory characteristics of products containing antioxidants such as green tea and cactus, were higher than those of Cont. in 7 days. A product including 0.5% green tea marked the best sensory score among antioxidants. Compared cost among 3 antioxidants, green tea was the cheapest. In the end, 0.5% green tea was selected as an optimal antioxidant to make high-quality oat chocolate. We made an end product by mixing green tea (0.5%) and oat. With respect to Hunter's color L (whiteness), a (redness) and b (yellowness), as green tea added, L and a level showed an increasing tendency. However, an opposition result was expressed in b level. When compared pH value and total acidity, it was statistically identical between Cont. and product with 0.5% green tea (G-0.5). There was different acid value among specimens. The acid value of G-0.5 was lower than that of Cont. up to 7 days, resulting in lower acid value than a ready-made product (D-Co.). When we assessed the sensory characteristics, G-0.5 was higher than other specimens such as Cont. and ready-made products (D-Co. and H-Co.) up to 6 days after manufacture. Put previous findings together, the addition of 0.5% green tea increased an antioxidative effect as well as the sensory acceptability of oat-chocolate.

• The Korean Journal of Food And Nutrition
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• v.28 no.3
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• pp.465-469
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• 2015

An analysis of changes in herbal tea composition according to the difference in processing conditions showed slightly reduced crude protein content and increased, moisture, crude fat and solid elution rate after treatment using the ash puffing process compared to roasting. Benzopyrene content was significantly reduced to 0.18 ppb from 0.51 ppb. This result indicated that, the $B({\alpha})P$ content differed depending on the processing condition and raw materials. Generation of food $B({\alpha})P$ is mainly include the thermal decomposition of food cooking, when the processing which is a main component of food carbohydrate, protein, fat reason despite severe heat treatment as a whole is to be detected even though the $B({\alpha})P$ in this way is considered to be. The taste, aroma and color did not show a large difference, but the strong bitters taste decreased.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.11
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• pp.1316-1326
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• 2017

We evaluated the proximate compositions of raw materials, total polyphenols, total flavonoids, and radical scavenging activities of roasted maize tea according to cultivation period and variety. Proximate compositions of raw materials were significantly different according to cultivation period and variety, and quality characteristics of roasted maize tea extracts were significantly different according to cultivation period. Total polyphenols, total flavonoids, and radical scavenging activities of roasted maize tea were significantly different before and after roasting. The total polyphenol content of Pyeonggangok cultivar sown on April 5th was elevated about 3.60-fold before and after roasting by $3.42{\pm}0.16$ and $12.22{\pm}0.67mg$ gallic acid equivalents/g, respectively. Overall, total polyphenol content was higher in roasted maize tea produced using maize sown on April 5th. 1,1-Diphenyl-2-picrylhydrazyl radical scavenging activity of Gangdaok cultivar sown on April 5th was elevated about 31.6-fold before and after roasting by $7.61{\pm}1.93$ and $240.37{\pm}8.82mg$ Trolox equivalents (TE)/g, respectively. 2,2'-Azino-bis-3-ethylbenzothiazoline-6-sulfonic acid radical scavenging activity of Pyeonggangok cultivar sown on April 5th was elevated about 5.5-fold before and after roasting by $153.84{\pm}1.32$ and $843.54{\pm}3.64mg$ TE/g, respectively. The correlation between proximate compositions of raw materials and quality as well as antioxidant characteristics of roasted maize tea showed overall significance.

• Korean Journal of Food Science and Technology
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• v.22 no.3
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• pp.241-247
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• 1990

In order to develop a type of instant tea cassia tora seed, changes of constiuent amounts before and after roasting $(3{\pm}0.5min\;at\;170{\pm}5^{\circ}C)$ effective extracting solvent and it's optimum concentration, dehydration method and sensory scores were investigated. Moisture, lipid, reducing sugar, emodin and rhein were decreased by roasting, whereas protein, and total sugar of cassia tora increased. Color intensity and extracting efficacy were also increased. Of three kinds of solvent (water, methanol and ethanol), ethanol was highest in redness and yellowness of exeracts, and filtrate yield. Effective extracting concentration of ethanol for cassia tora was 50%(V/V). Freeze dry product(FDP) and spary dry product(SDP) showed coffee and aloe-like smell, coffee like brown color, rapid soluble in cold and hot water, and fast caking in air during storage. Free sugar contents were high in order of raffinose>fructose >glucose>maltose>sucrose Metallic contents were high in order of sodium>calcium>potassium>magnesium>iron. In sensory score for color, taste and aroma, FDP and SDP were both above 8.0 point, however, of them FDP more or less higher than SDP In addion, score in developing value as an instant tea was above 8.0 point (valuable).

• Journal of Society of Preventive Korean Medicine
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• v.22 no.1
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• pp.81-90
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• 2018

Objectives : The aim of this study is to analyze the patent trend in Traditional Korean Tea. In this paper, we investigate the diversity of Korean Tea registered as patents focusing on the kinds of medicinal herbs used, processing methods, and types of tea. Methods : We collected patents data using KIPRIS, and WIPS database. We conducted Quantitative Analysis by year and main patentee, and Qualitative Analysis by patent's contents. Results : 313 patents are selected from 2001 to May 2017. The number of patents have been on the rise and reached 44 in 2014. Individuals have registered the most patents, followed by companies, Industry-University Cooperation Foundation, and local autonomous entities. Ginger, Omija and Cactus were used at high frequency among 109 tea containing one medicinal herb. Licorice and Jujube were frequently used among 204 tea containing more than two kinds of medicinal herbs. In classification of patent by efficacy, 'health promotion and function recovery' and 'treatment and prevention of diseases' are most frequently specified. 128 patents are presenting processing methods for medicinal herbs in the order of roasting, fermentation, and fumigation. Among 164 patents presenting tea types, liquid type accounts for more than half and there are 67 leached tea, and 32 powder tea. Conclusion : The analyses results showed that lots of new recipes, efficacy, processing methods and tea types are being studied and registered as patents. In order to help Traditional Korean Tea industry to develop, active patent registration and further study about up-to-date patent trend would be required.

• The Korean Journal of Food And Nutrition
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• v.30 no.6
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• pp.1149-1156
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• 2017

We investigated the quality characteristics and the antioxidant efficacy of roasted maize tea according to different moisture contents (9% to 14%) using the puffing system (PS) and the roasting system (RS). Compared with the RS, the PS caused higher turbidity (0.017 vs. 0.003 in PS-14% vs. RS-14%), brown color intensity (0.170 vs. 0.059 in PS-14% vs. RS-14%), a-values (0.20 vs. -0.44 in PS-14% vs. RS-14%), b-values (7.90 vs. 5.57 in PS-14% vs. RS-14%), and a lower L-value (19.67 vs. 21.03 in PS-14% vs. RS-14%). Total polyphenol and flavonoid contents of roasted maize tea were increased along with the moisture content and they were higher with the PS (polyphenol; 5.95 mg GAE/g, flavonoids; 1.27 CE/g in PS-14%) than with the RS (polyphenol; 5.39 mg GAE/g, flavonoids; 1.12 mg CE/g in RS-14%). The DPPH and ABTS radical scavenging effects of roasted maize tea were also increased along with the moisture content, and the scavenging efficacy was significantly higher with the PS (DPPH; 160 mg TE/100g, ABTS; 507 mg TE/100g in PS-14%) compared with the RS (DPPH; 120 mg TE/100g, ABTS; 362 mg TE/100g in RS-14%). The polyphenol levels were significantly correlated with turbidity, brown color intensity, and L, a, and b-values of the roasted maize tea. In addition, an increase of the total polyphenol content in roasted maize tea induced antioxidant activities. As a result, an increase in polyphenols during the roasting process induced antioxidant activities which could prevent damage from free radicals.

• Food Science and Preservation
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• v.11 no.2
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• pp.148-153
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• 2004

The organoleptic properties of granule tea was optimized for granulation of Polygonatum sibiricum Delar(Dunggulle) tea for exclusion of scorched smell and increase of consumption. The length of 2 mm was suitable to cutting size of Dunggulle for preparation of the roasted Dunggulle. The optimum sensory conditions for aroma of Dunggulle granule tea showing 7.85 organoleptic score were 80.61% in ratio of Dunggulle extracts to total extracts, 12.77% in content of total extracts and 37.33% in rate of glucose to total sugar. The highest score of overall palatability was 5.96 at 61.11% in rate of Dunggulle extracts to total extracts, 13.79% in content of total extracts, and 60.92% in rate of glucose to total sugar.

• Preventive Nutrition and Food Science
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• v.10 no.1
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• pp.1-5
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• 2005

Eight flavonoids, apigenin-6-C-β-D-glucopyranosy l-8-C-β-D-glucopyranoside (AGG), quercetin 7-O-β-D­glucopyranoside (QG), luteolin 7-O-β-D-glucopyranoside (LG), quercetin 7-O-(6'-O-acetyl)-β-D-glucopyranoside (QAG), luteolin 7-O-(6'-O-acetyl)-β-D-glucopyranoside(LAG), quercetin (Q), luteolin (L) and acacetin 7-O-β­D-glucuronide (AG) were determined by HPLC in the safflower (Carthamus tinctorius L.) leaf during growth and processing. During growth, levels of five flavonoid glycosides (AGG, QG, LG, QAG, & LAG) in the leaf increased progressively at over time according to growth stages, reached a maximum before June 11, and then decreased sharply, while those of three flavonoid aglycones (Q, L, & AG) increased greatly at the early stage of growth, reached a peak before May 28, and then decreased rapidly. During the steaming process, contents of five flavonoid glycosides increased rapidly with increased steaming time, reached a maximum after 5 min of steaming, and then decreased, whereas those of flavonoid aglycones except for AG decreased sharply with increased steaming time. During the roasting process, contents of three flavonoid glycosides decreased rapidly with increased roasting time, whereas those of two acetylflavonoid glycosides (QAG & LAG) and three flavonoid aglycones increased progressively with increased roasting time, reached a maximum after 3 min of roasting, and then decreased. These results suggest that appropriate steamed and roasted safflower leaves are a rich source of flavonoids, and may be a good source of bioactive components as a functional leaf tea.