Comparison of magnesium amount in black, green, fruit, and herbal teas
M. Zeiner, M. Kröppl, I. Juranovic-Cindric, G. Stingeder - Comparison of magnesium amount in black, green, fruit, and herbal teas - European Chemical Bulletin, Vol. 2, No. 3, 2012, pp. 99-102
The diet is the main source of minerals and trace elements, thus exposure to dietary essential elements has a direct impact on human health.
Magnesium is a major component of the bones, but furthermore it influences the nervous system and muscle activity. Therefore its needs
must be met via nutrition. There is a non-negligible discrepancy between intake and requirements. So magnesium is often uptaken in form
of nutrition supplements. Thus there is an interest in the amount of magnesium in natural products, where it is supposed to vary. In this
study, various commercially available tea bags of different kinds of tea (black tea, green tea, fruit tea and herbal tea) were analysed for their
magnesium content. After a microwave assisted digestion with nitric acid and water at temperatures up to 220°C, the element concentration
was measured with ICP-OES (inductively coupled plasma-optical emission spectroscopy) as it is a simultaneous, fast and reliable method
with low detection limits. All samples were prepared in duplicate. In all samples high amounts of magnesium (approx. 1 g kg-1) could be
found. No statistically significant differences were registered between the different classes of teas.