Effect of extraction time and temperature on the content of catechins in white tea water extracts
2008
Mika, M. | Wikiera, A. | Zyla, K.,Uniwersytet Rolniczy, Krakow (Poland). Katedra Biotechnologii Zywnosci
Non-fermented tea is a rich source of flavan 3-ols that have antioxidative properties. Catechin gallates, which belong to the (-) forms (2S, 3R) eliminate cholesterol from the micelles formed by bile acids in the most effective way. High temperature causes the epimerization of flavan 3-ols and the increase in the amounts of the (-) forms (2S, 3R). In the paper the effect of temperature and time of extraction of dried white tea leaves was investigated on the total amount of flavan 3-ols, on the percent share of the (-) fraction of the forms (2S, 3R), and the percent share of catechins containing gallic acid radical in their molecule. It was showed that the composition of catechin preparations could be moulded by changing the conditions of tea extraction
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