DETERMINATION OF ELEMENT CONTENTS IN COMMERCIAL TEAS MARKETED IN MALAYSIA & ITS INFUSION RESIDUE USING NEUTRON ACTIVATION ANALYSIS (NAA)

Abstract

Fifteen elements in black tea, rose flavoured tea and fruit tea commercially sold in Malaysian market were determined using neutron activation analysis (NAA). The elements analyzed include Al, Ba, Br, Ce, Cl, Eu, Fe, K, La, Mg, Mn, Na, Rb, Sc, and Zn. The concentration of these elements varied according to the tea types in the range of 2.2% K to 0.04 mg/kg Sc. The quality of analysis was assured using certified standard reference material. Infusion study of the tea residue was also performed to analyse the possible consumption of these elements by the population. Ce, Cl, Eu, K and Rb were found to be easily infused in all three types of teas. Kruskal-Wallis test found significant differences (p < 0.05) between elemental composition and types of teas. Principal component analysis (PCA) showed clustering based on types of teas.