不同茶类冲泡过程中稀土浸出率试验分析

用ICP-AES方法测定茶叶中稀土含量,并通过多次冲泡分析稀土浸出情况。结果表明,实验用茶样中稀土均能随冲泡不同程度溶入茶汤中,8种茶样的稀土浸出率与原稀土含量的高低不存在明显的线性关系,三次冲泡稀土浸出率在13%~26%之间。本次实验得出工夫红茶的三次冲泡浸出率为25.42%,钱塘龙井和普洱的三次冲泡浸出率相对最低,分别为13.89%和13.59%。除金尖和铁观音外,其余6种茶样的第一次浸出率最高,且随着浸泡次数的增多浸出速率逐渐降低。

The Preliminary Study on Rare-Earth Oxides Leaching Rate of the Different Tea Brewing Process

Determination the rare earth content in tea by ICP-AES,and analysis of the leaching rate through several brewing.Results showed that rare earth in tea can be extracted with varying degrees by brewing.The relationship between third brewing leaching rate and content of rare earth in original tea is not obvious.The leaching rate of rare earth from tea is between 13%~26%,and the Gongfu black tea is 25.42%,the lowest is Qiantang-longjin and puer tea,there are 13.89% and 13.59% respectively.And with the increase in the number brewing,rare earth leaching rates were reduced by most of tea except Jijian tea and Tieguanyin tea.