摘要
为了解不同浸提方式在茶叶微量元素测定中的影响,采集市售云南普洱成品茶,分别采用热水浸提、稀酸热浸提、超声辅助常温水浸提以及干法灰化处理,火焰原子吸收法同时测定Ca、Mg、Zn含量。各元素标准曲线线性关系良好,R2≥0.9905。在不同浸提方式中,稀酸热浸提的Mg和Zn元素析出量最高,干法灰化稀硝酸浸提的Ca元素析出量最高;两种热浸提茶叶中元素含量都是镁>钙>锌;超声辅助常温水浸提以及干法灰化稀酸浸提茶叶中元素含量都是钙>镁>锌。通过不同的浸提方式处理样品,能同时测定多种元素,准确度和精密度都符合实验要求。
In order to understand the influence of different extraction methods on the determination of trace elements in tea,Yunnan Puer tea was collected from the market.Hot water extraction,dilute acid hot extraction,ultrasonic-assisted normal temperature water extraction and dry ashing were used respectively.The content of calcium,magnesium and zinc in tea was determined simultaneously by flame atomic absorption spectrophotometry.The standard curve of each element has good linearity,the R2≥0.9905.Among the different leaching methods,the precipitation of Mg and Zn elements in dilute acid hot leaching is the highest,and the precipitation of Ca element in dry ashing dilute nitric acid leaching is the highest;the content of elements in the two kinds of hot extracted tea is magnesium>calcium>zinc;the content of elements in leaves is calcium>magnesium>zinc during ultrasonicassisted water extraction at normal temperature and dry ashing dilute acid extraction.By treating samples with different extraction methods,multiple elements can be determined at the same time.The accuracy and precision meet the experimental requirements.
作者
刘艳
陈碧芬
董艳杰
吴隽恺
LIU Yan;CHEN Bifen;DONG Yanjie;WU Junkai(School of Chemical Engineering,Ningbo Polytechnic,Ningbo 315800,China)
出处
《食品安全导刊》
2023年第8期48-50,54,共4页
China Food Safety Magazine
关键词
浸提方式
普洱茶
微量元素
析出
extraction method
Puer tea
trace elements
release
