Caffeine Content Investigation in the Turkish Black Teas

Tea is a widely consumed beverage that contains many components. Caffeine belongs to this group of components called alkaloids contain nitrogen. In this study caffeine contents of three types of Turkish teas are determined by using extraction method. After condensation process, residue of caffeine and oil are obtained with evaporation. The oil which is in the residue is removed by hot water. Extraction process performed by using chloroform and the crude caffeine is obtained. From the results of experiments, caffeine contents are found in black tea, green tea and earl grey tea as 3.57±0.43%, 3.11±0.02%, 4.29±0.27%, respectively. Caffeine contents which are found in 1, 5 and 10 cups of tea are calculated. Furthermore, the daily intake of caffeine from black teas that affects human health is investigated.





References:
[1] D. Desideri, M.A.Meli, C. Roselli, L. Feduzi, 2011, Polarized X Ray
Fluorescence Spectrometer (EDPXRF) for the Determination of
Essential and Non Essential Elements in Tea
[2] Rachel R. McCusker, Bruce A. Goldberger, and Edward J. Cone,
Caffeine Content of Specialty Coffees, Journal of Analytical
Toxicology, Vol. 27, October 2003
[3] M. A. Herrador, A. G. Gonzalez, 2000, Pattern Recognition Procedures
for Differentiation of Green, Black and Oolong Teas According to Their
Metal Content from Inductively Coupled Plasma Atomic Emission
Spectrometry
[4] http://www.naturestealeaf.com/review/product/list/id/449/ retried on
20/03/2013
[5] http://coffeetea.about.com/od/typesoftea/a/Earl-Grey-Tea.htm
[6] Bibby Scientific The quantitative determination of caffeine in beverages
and soft drinks using UV wavelength spectroscopy
[7] Instıtute of Chemıcal Technology Prague, Direct analysis of caffeine in
soft drinks and coffee and tea infusions.
[8] NS207 Lab3- Isolation of Caffeine From Tea
[9] K.L. Mandiwana, N. Panichev, S. Panicheva, 2011, Determination of
Chromium(VI) in Black, Green and Herbal Teas
[10] http://tr.wikipedia.org/wiki/Kafein retried on 15/03/2013
[11] International Food Information Council Foundation, Caffeine & Health:
Clarifying The Controversies
[12] http://www.milk.mb.ca/nutritionOrder/pdf retried on 19/03/2013
[13] K.L. Mandiwana, N. Panichev, S. Panicheva, 2011, Determination of
Chromium(VI) in Black, Green and Herbal Teas