| 摘要: |
| 以湖南安化天尖、茯砖及广西六堡3种黑茶为考察对象，研究黑茶中茶多酚的提取工艺以及抗氧化性能。针对超声波不同提取条件，采用正交试验，确定黑茶中茶多酚的最佳提取工艺条件；采用清除二苯代苦味酰自由基（DPPH）的能力和邻苯三酚自氧化体系来评价其抗氧化活性。结果表明：采用超声波热水复合浸提法提取黑茶中茶多酚的最佳提取条件为超声波提取功率250 W，提取固液比1∶25，提取温度55℃，提取时间45 min，茯砖黑茶中茶多酚的提取率5.21%；同时测得茯砖黑茶具有较好的抗氧化能力，对DPPH自由基有较强的清除能力，但与维生素C（VC）相比，其抗氧化能力比VC的能力弱；其清除超氧阴离子自由基能力的IC50为0.507 μg/mL。 |
| 关键词: 黑茶 茶多酚 提取 抗氧化性 |
| DOI：10.11841/j.issn.1007-4333.2017.09.13 |
| 投稿时间：2016-08-04 |
| 基金项目:中央高校基本科研业务费专项资金项目（2015ZCQ-LY-03）；北京林业大学大学生创新创业训练项目（S201510022098） |
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| Studies on polyphenols extraction technology and the performance of the antioxidants arising from dark tea |
|
CHEN Hongyan, LI Yuhao, CEN Haobin
|
| (School of Science, Beijing Forestry University, Beijing 100083, China) |
| Abstract: |
| To optimize the tea polyphenols extraction process,the method of ultrasonic-assisted water extracting was selected to discover the best conditions by an orthogonal experiment.In terms of the antioxidant performance appraisal,the scavenging rate of hydroxyl radical and superoxide anion radical were employed two indexes.The best ultrasonic-assisted water extracting conditions of tea polyphenols were as follows:Ultrasonic power 250 W;Tea-leaves mass to water volume ratio 1:25;Extracting temperature 55℃;Extracting time 45 minutes;and the best tea category,Fuzhuan tea.The extracting rate of Fuzhuan tea polyphenols reached 5.21%.Meanwhile,through the antioxidant performance test,Fuzhuan tea was estimated to be good in resisting oxidation,but its anti-oxidant activity was lower than that of VC.Itshowed excellent free radicals scavenging capacity to DPPH and its IC50 was 0.507 μ g/mL. |
| Key words: dark tea tea polyphenols extraction antioxidant properties |
