Total Phenol, Catechin, and Caffeine Contents of Teas Commonly Consumed in the United Kingdom

Published on Jan 1, 2002in Journal of Agricultural and Food Chemistry3.571
· DOI :10.1021/jf010153l
Santosh Khokhar13
Estimated H-index: 13
(University of Leeds),
S. G. M. Magnusdottir1
Estimated H-index: 1
(University of Leeds)
Levels of total phenol, catechins, and caffeine in teas commonly consumed in the United Kingdom have been determined using reversed phase high-performance liquid chromatography. Tea bags or tea leaves were purchased from local supermarkets and extracted in boiling water for 5 min. The resulting data showed considerable variability in both total phenols [80.5−134.9 mg/g of dry matter (DM) in black teas and 87−106.2 mg/g of DM in green teas] and catechins (5.6−47.5, 51.5−84.3, and 8.5−13.9 mg/g of DM in black, green, and fruit teas, respectively); this was most probably a result of differing agronomic conditions, leaf age, and storage during and after transport, as well as the degree of fermentation. Caffeine contents of black teas (22−28 mg/g of DM) were significantly higher than in less fermented green teas (11−20 mg/g of DM). The relative concentration of the five major tea catechins ranked EGCG > ECG > EC > EGC > C. The estimated U.K. dietary intakes of total tea catechins, calculated on the basis of an...
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