• Food Science and Biotechnology
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• 제14권2호
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• pp.196-199
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• 2005

Antimicrobial activity of persimmon leaf tea methanol extracts on Klebsiella pneumoniae and Staphylococcus aureus was examined through paper disk diffusion bioassay. K. pneumoniae and S. aureus showed 87.64 and 99.35% growth inhibitions by addition of steamed tea methanol extracts (10 mg/ml), respectively. The number of microorganisms in rice cakes was significantly reduced when leaf tea powder was added during production of rice cakes. Addition of 1% steamed leaf teas to rice cakes decreased the number of microorganisms by over 50%, and over 70% reduction was observed when final 2% (dried weight w/w) steamed leaf tea was added, whereas no significant effect was observed over 2%. These results indicate that different microorganisms were detected from persimmon leaf and rice cake, and persimmon leaf can inhibit normal microbial growth in rice cake.

• 한국의류학회지
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• 제23권1호
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• pp.140-146
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• 1999

Colorants in green tea were extracted freeze-dried and analyzed to investigate the possibility of using as a natural dye. Fractionation of the colorants was carried out by column chromatograpy. Colorants in green tea were eluted into five fractions. All the fractions except fraction F2 showed absorption peakat 280nm. Fraction f2 showed absorption peak at 270nm and broad peak at 350nm, From the IR analysis it is speculated that fractions F2-F5 having similar stucture but different molecular weight are catechis. Silk fabrics dyes with fractions F1-F4 showed yellowish red color while sample dyed with fraction F5 showed red color. The colorants from green tea infusion was applied to silk wool nylon cotton and rayon fabrices. It showed relatively good affinity to protein and polyamide fibers bur low affinity to cellulose and regenerated cellulose fibers.

• 한국식품조리과학회지
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• 제16권5호
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• pp.390-393
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• 2000

Salmonella typhimurium TA98 streptomycin 의존성 SD510 균주를 사용하여 녹차의 수용성 추출물과 에탄을 용해성 추출물에 대한 항변이 효과를 검토하였다. 4-NQO에 대한 항변이 활성은 수용성 추출물과 에탄을 용해성 추출물 모두에서 추출물의 투여량이 증가할수록 높았으며, 억제효과는 5월과 8월 순 녹차 추출물을 1,000$\mu\textrm{g}$/plate 투여했을 때 각각 93% 및 95%로 나타났다. Trp-P-1에 대한 항변이 활성은 에탄을 용해성 추출물의 경우 53.3~921.%로서 투여농도가 증가할수록 억제 효과가 높았다. 그러나 수용성 추출물은 투여농도가 증가할수록 항변이 활성이 감소하였다.

• Bulletin of the Korean Chemical Society
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• 제26권5호
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• pp.747-754
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• 2005

Liquid chromatographic methods with UV and fluorescence detection have been used to determine the levels of (+)-catechin, (-)-epicatechin, (-)-epicatechin gallate, and (-)-epigallocatechin gallate in Korean green tea infusions. The extracts of Korean green tea leaves or powders in water at various temperatures (100 ${^{\circ}C}$, 80 ${^{\circ}C}$, 60 ${^{\circ}C}$) and time, were washed with chloroform and re-extracted to ethyl acetate. The ethyl acetate phase was dried and re-dissolved in methanol and analyzed. Five catechin compounds were separated by gradient elution. The flavonoids were found decomposed on prolonged extraction, thus exhaustive extraction by a Soxhlet apparatus was found useless for green tea. Some unknown components were found in the extracts at 100 ${^{\circ}C}$. When the green tea was filtered and re-extracted with new fresh water, still some flavonoids were extracted. However, the contents of flavonoids in the third extract were found negligible. The flavonoid extraction rate of green tea powders was higher than that of green tea leaves, but flavonoid decomposition of green tea powders was also faster than that of green tea leaves. The traditional way of drinking green tea was found appropriate in view of flavonoids intake.

• Journal of Applied Biological Chemistry
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• 제55권2호
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• pp.95-101
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• 2012

본 논문에서는 오죽(Phyllostachys nigra Munro)의 잎과 죽순을 사용하여 차 가공공정을 통한 오죽잎차와 오죽죽순차가 제조되었고, 이들에 대한 영양성분 분석을 실시하였다. 뿐만 아니라, 일반적인 차를 음용하는 조건($80^{\circ}C$ 물, 10분)에서 이들 차로부터 얻을 수 있는 수용성 물질의 추출율과 총 폴리페놀 함량, 총 플라보노이드 함량이 가공되지 않은 오죽 원재료 및 마테차, 녹차와 비교되었다. 마지막으로 차 음료에 포함된 항산화능과 각 항산화 화합물을 탐색하고자 온라인, 오프라인 항산화 분석이 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) and di(phenyl)-(2,4,6trinitrophenyl)iminoazanium (DPPH) 라디칼에 대해서 이루어졌다. 본 논문의 결과는 오죽으로부터 제조된 이들 차가 다양한 영양성분을 함유하고 있고, 건강에 이로운 전통차로 음용될 수 있음을 보여주었다.

• 한국식품조리과학회지
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• 제19권3호
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• pp.318-323
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• 2003

본 연구는 미역과 된장, 멸치 엑기스, 다시마 엑기스, 바지락 엑기스, 파, 감자, 양파가루, 마늘가루를 이용하여 1조각이 1인분이 되도록 블록을 만들어 동결 건조시킨 후 이화학적 특성을 측정한 결과는 다음과 같다. 일반성분의 경우 제품 100 g당 조 단백의 경우 녹차 미역 된장제품에 비하여 일반 미역 된장제품의 단백질 함량이 약간 높게 나타났으며, 조 지방 함량은 일반 제품이 녹차 제품보다 1% 정도 함량이 많았으며, 탄수화물 함량은 일반 미역 된장제품보다 녹차 미역 된장제품이 약간 높게 나타났다. 회분 함량은 일반 미역 된장 제품이 녹차제품에 비해 높게 나타났다. 유리아미노산 구성에서 두 제품 모두 많은 양을 나타낸 아미노산은 alanine, phenylalanine, hydroxyproline, valine, leucine, isoleucine, Iysine 등이었으며, 대부분이 일반 미역 된장제품에 비하여 녹차 미역 된장제품의 아미노산함량이 높게 나타났다. 지방산의 조성에서 포화지방산, 단일 불포화지방산과 다가 불포화지방산의 비율은 두 제품간의 차이가 별로 없었으며, 포화지방산중에서는 palmitic acid가 가장 높게 나타났고, 단일불포화 지방산은 oleic acid, 다가 불포화지방산은 linoleic acid가 가장 높은 비율을 나타냈다. 제품의 포화 지방산과 불포화지방산의 비율은 26:74로, 불포화지방산은 단일불포화지방산에 비해 다가 불포화지방산의 비율이 두배 이상 높게 나타났다. 미역 된장제품에서 가장 많은 함량을 나타낸 유기산은 oxalic acid, 다음으로 tartaric acid였으며, 대부분 녹차제품의 유기산 함량이 높게 나타났다. 관능평가에서 맛, 색, 전반적인 기호도에서는 유의적인 차이가 없었으나, 냄새의 경우 일반 시판 된장제품이 녹차제품에 비하여 유의적으로 높게 나타났다 본 연구제품의 개발로 바쁜 현대인들 특히 맞벌이, 독신자들에게 건강을 증진시키는 효과를 가지면서 간편한 방법으로 미역 된장국을 끓여 먹을 수 있는 상품을 제공하고자 하였다.

• 한국임상약학회지
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• 제28권4호
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• pp.342-346
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• 2018

Background: Green tea extracts are approved as nonprescription drug and available as health functional foods, health foods, and beverages. Clinical information on the products is lacking. Methods: Information about the products on green tea nonprescription drugs was obtained from the website of the Korea Pharmaceutical Information Center. The Naver, i.e., a top ranking online search portal, was used for compiling the list of the health functional food products using key words of 'green tea catechin' on August 23, 2018. The recommended daily dosages of catechins were calculated as 30% of the total dried mass of green tea and about 50% of the catechins were considered as epigallocatechin gallate (EGCG). Results: A total of two types of nonprescription drugs containing green tea powder or extracts, nine health functional food products, and three types of health foods were found. The regulatory requirements of the EGCG exceeding 800 mg were reported to be associated with adverse effects of elevated liver enzyme. If consumers take several green tea products concurrently, such as nonprescription drugs with health functional foods or health foods, it could exceed the recommended amount of EGCG. Conclusion: The concurrent use of green tea products as nonprescription drugs, health functional foods, and healthy foods may lead to an increased exposure to EGCG. Pharmacists should be aware the availability of various types of green tea products and the potential risk of liver toxicity due to excessive consumption of EGCG.

• 한국식품과학회지
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• 제48권1호
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• pp.42-47
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• 2016

오미자의 이용성 확대를 위한 건조 가공 제품의 가능성을 확인해보고자 생오미자 및 건조오미자를 이용하여 착즙, 추출, 동결건조, 과립성형 및 분무건조 등의 방법을 이용하여 다양한 오미자분말차를 제조하여 그 품질 특성을 비교 분석하였다. PG, EG 및 ES의 총가용성고형분 함량 및 탁도의 경우 다른 구에 비해 유의적으로 높았으며, pH 측정 결과 PG 및 EG가 다른 구보다 유의적으로 높았다. PG 및 EG의 색도 측정 결과 다른 구에 비해 높은 $L^*$값, 낮은 $a^*$값 및 $b^*$값으로 나타나 오미자의 가공 형태에 따른 유의적 차이가 뚜렷함을 알 수 있었다. PG 및 EG의 경우 다른 구에 비해 유의적으로 높은 환원당 함량, 낮은 총 페놀성 화합물의 함량, 낮은 항산화활성, 낮은 총 안토시아닌 함량 및 낮은 schizandrin 함량을 보여 오미자의 가공 형태에 따른 유의적 차이를 확인할 수 있었다. 또한 관능검사 결과 PG 및 EG는 낮은 붉은색 정도, 낮은 탁도 정도, 낮은 신맛 정도, 높은 쓴맛 정도 및 높은 단맛 정도를 보였으며, 종합적 기호도에서 PG 및 ES의 경우 가장 높은 점수를 받았다. 이와 같은 결과에서 붉은색과 항산화 활성, 안토시아닌 및 schizandrin 함량이 우수한 오미자 분말 제품을 위해 과립차보다 동결건조 및 분무건조분말차가 바람직하다고 판단된다.

• Preventive Nutrition and Food Science
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• 제8권2호
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• pp.185-190
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• 2003

Gamma irradiation was used as part of a new processing method to produce a brighter-colored and mild-flavored green tea leaf extract that retained all of its physiological activities. Dried green tea leaf was extracted with 70% ethanol and gamma irradiated at 0,5, 10, 20 kGy. Hunter color $L^{*}$- and $a^{*}$-values were increased with irradiation in a dose-dependent manner, which was a color range from dark brown to bright yellow. However, the irradiation effect gradually disappeared during 3 weeks of storage, with color reverting to that of untreated samples. There was no difference in the radical scavenging and tyrosinase inhibition effect by irradiation. Among antioxidants used, ascorbic acid was the most effective against color reversion. In contrast, cysteine was shown to protect the effect of color change with irradiation. Results indicated that enhanced color of irradiated green tea leaf extract can be effectively controlled by additives such as ascorbic acid and a low storage temperature.e.e.

• 한국수산과학회지
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• 제39권2호
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• pp.85-93
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• 2006

This study was conducted to evaluate the optimal processing conditions of smoke-dried powdered oysters and to determine their shelf-life during storage for development of a natural oyster flavoring substance. The optimal conditions for processing of smoke-dried oyster powder with freshy oyster were as follows. Raw shelled oysters were rinsed with 3% saline solution, drained, boiled for 10 minutes at $98^{\circ}C$, and then smoked for 1 hour at $50^{\circ}C$, followed by drying for 4 hours at $80^{\circ}C$ Smoke-dried oyster powder with oyster scraps were prepared as flavoring material. The smoked oyster scraps were submerged in oyster sauce far 10 minutes at room temperature and then dried with hot air for 5 hours at $50^{\circ}C$. The smoke-dried oysters and smoke-dried oyster scraps were then pulverized to 50 mesh and packed in tea bags or vacuum-packed in laminated plastic film bags (PE/PVDC/CPP, $12{\mu}m/15{\mu}m/50{\mu}m$). Compared to non smoke-dried powdered oysters, the smoking and dipping in oyster sauce enhanced the flavor and prevented lipid oxidation of the smoke-dried powdered oyster product. Shelf-life tests indicated that the vacuum-packaging method preserved the quality of smoke-dried powdered oysters stored for 150 days at room temperature.