减压升华法从低等级绿茶中提取茶多酚

为探寻采用减压升华法提取茶多酚的较佳条件,以云南省双柏县产的低档绿茶作为供试样品,研究了提取温度、提取时间和茶叶粒度对茶多酚提取率的影响,并比较了有机溶剂浸提法和减压升华法对茶多酚的提取效果。结果表明,在压力约8×104 Pa、提取温度145℃时干馏升华25min,茶多酚的提取率为11.80%,纯度高达91.2%。升华法提取的茶多酚纯度高于有机溶剂浸提法提取的茶多酚,提取成本低,无化学物质残留,且环境友好。

Using Decompression Sublimation to Extract Tea Polyphenol from Low-grade Green Tea

In order to investigate the optimal conditions of extracting polyphenol by decompression sublimation,the low-grade green tea from Shuangbai county(Yunnan province),as an example,has been studied to discover the effect of extraction temperature and time as well as tea granularity upon the extraction ratio in decompression sublimation process,and make a comparison between decompression sublimation and organic-solvent extraction process.Experimental results showed that the extraction ratio of tea polyphenol by decompression sublimation was 11.80%,and its purity was 91.2% under the pressure of 8×104 Pa,temperature of 145 ℃,and retorting time of 25 min.In short,its product is purer than that of organic-solvent extraction,and has some advantages such as low cost,no chemical residue as well as environment-friendly.