采用火焰原子吸收光谱法分别测定绿茶和红茶中铜、铁、锰和锌的浸出量，进而研究冲泡茶叶时间与微量元素浸出量的关系．在冲泡时间为2～20 min时，测定了绿茶（红茶）中微量元素的浸出量：铜为0.0688～0.1149（0.0645～0.1403）μg· mL－1，锰为0.8559～2.3341（0.8045～2.1387）μg· mL－1，铁为0.1515～0.2075（0.1473～0.2088）μg· mL－1，锌为0.1499～0.1919（0.1399～0.1857）μg · mL－1．方法的回收率和相对标准偏差（ n＝5）为90.9％～103.1％和0.10％～0.82％．研究表明，当茶叶浸泡时间在2～10 min时，微量元素浸出量随时间的增加而增加，10 min后趋于平稳．因此，从微量元素的角度分析，茶叶的最佳冲泡时间为10 min．%The extractive amount of Cu , Mn, Fe and Zn in green tea and black tea was determined by FAAS , and the relationship between the soaking time of tea and the extractive amount was discussed .When the soaking time was 2~20 min,the extractive amounts of Cu , Mn, Fe and Zn in green tea ( black tea) were 0.068 8 ~0.114 9(0.064 5~0.140 3)μg· mL-1 , 0.855 9~2.334 1(0.804 5~2.138 7)μg· mL-1 , 0.151 5~0.207 5 (0.1473~0.2088)μg· mL-1 and 0.1499~0.1919 (0.1399~0.1857)μg· mL -1, respectively.The recov-ery was 90.9%~103.1%and RSD ( n=5 ) was 0.10%~0.82%.Results showed that the extractive amount of Cu, Mn, Fe and Zn increased with the increase of soaking time in 2~10 min and it tended to be stable above 10 min.Therefore, from the perspective of microelements , 10 min was selected as the optimum soaking time .
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