富硒绿茶中锌、硒、铅、铝的溶出研究

目的研究富硒绿茶冲泡过程锌、硒、铅、铝4个元素的溶出,为科学饮茶提供指导。方法通过在实验室模拟茶叶冲泡过程,采用电感耦合等离子体质谱(inductively coupled plasma-mass spectrometry,ICP-MS)测试了不同冲泡时间和不同冲泡次数下茶汤中锌、硒、铅、铝的溶出率。结果锌、硒的溶出在30 min内相对增长较快,并且经3~4次冲泡溶出可溶出部分达80%;铅在5 min内和第1次冲泡溶出可溶出部分达50%以上;铝在整个过程溶出平稳,总溶出率小于10%。结论锌、硒、铅、铝4个元素在不同冲泡时间和不同冲泡次数下溶出性不一致;适度洗茶,可以去除较多铅的可溶性部分,而锌、硒损失较少;长时间浸泡和多次冲泡后,各元素溶出量增加较少。

Dissolution of zinc, selenium, lead and aluminum in selenium enriched green tea

Objective For guiding scientific tea, this paper studied the dissolution case of zinc, selenium, lead and aluminum in the brewing process of enriched Se green tea. Methods Dissolution rate of zinc, selenium, lead and aluminum in tea was determined by inductively coupled plasma mass spectrometry (ICP-MS). Results The dissolution of zinc and selenium relative grew rapidly in 30 min; it was more than 80% leachable after 3 to 4 times brewing. The dissolution of lead was more than 50% leachable within 5 min and first brewing. The dissolution of aluminum was stable in the whole process, which was less than 10%.Conclusion At different brewing times and frequencies, the dissolutions of zinc, selenium, lead and aluminum were inconsistent. By washing the tea moderately, more soluble lead could be removed and less zinc and selenium be lost. After a long soak and brewing several times, the dissolution increase of the elements in tea was less.