Optimization of Tea Sample Preparation Methods for ICP-MS and Application to Verification of Chinese Tea Authenticity

Abstract

In this study, 35 black, oolong, and green tea samples from China were analyzed by inductively coupled plasma mass spectrometry after a digestion method was developed on the basis of a response surface methodology. Linear discriminant analysis of whole data sets was performed in order to discriminate and classify Chinese tea samples according to their origin and type. The analysis revealed an excellent separation between tea samples according to their type and origin with a discrimination efficiency of 100%. The varieties of selected elements in Chinese tea were analyzed based on their origins and types.