DETERMINATION OF TRACE ELEMENTS IN SOME BRANDS OF GREEN TEA USING WET DIGESTION, INFUSION AND DRY ASHING METHODS
Keywords:Green Tea, infusion, wet digestion, dry ashing, trace elements, Camellia sinensis
The concentrations of trace elements (Cu, Zn, Fe, Mn and Ni) in some commercially available brands of green tea sold within Katsina metropolis coded (SGT, HGT, LGT, AGT and GGT) were determined using wet acid digestion, water infusion, and Dry Ashing methods by Atomic Absorption Spectroscopy (AAS). Among the trace elements analyzed Nickel and Manganese recorded the highest value ranged 1.0 – 3.5 mg kg-1 and1.0 – 5.5 mg kg-1 in dry ashing and wet digestion respectively. Fortunately, almost all the elements analyzed were within the standard permissible limit of WHO. The content of trace elements was found highest in the Dry Ashing method and lowest values recorded in tea infusion. The contributory factors responsible for the differences found in tea samples could be from a varying concentration of metals in the soil, conditions of cultivation and preparations, and these vary between both countries of origin and for the type of tea. Further work is recommended on these brands to study other important parameters
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