Flavanol composition and caffeine content of green leaf as quality potential indicators of Kenyan black teas
1997
Obanda, M. | Owuor, P.O. | Taylor, S.J.
The flavanol composition and caffeine content of green tea leaf, black tea quality parameters of theaflavins, thearubigins, liquor brightness and total colour varied more among clones than with time of the year. In green leaf, either (-)epicatechin gallate or (-)epigallocatechin gallate was the dominant flavanol present. Regression analysis of tasters' preferences for black teas against green leaf chemical components showed positive and significant correlations for (-)epicatechin gallate (r = 0.498, P less than or equal to 0.05 for taster A; r = 0.665, P less than or equal to 0.01 for taster B, and r = 0.678, P less than or equal to 0.01 for both tasters' overall ranking), (-)epigallocatechin gallate (r = 0.513, P less than or equal to 0.05 for taster B; r = 0.532, P less than or equal to 0.05 for both tasters' overall ranking and caffeine (r = 0.523, P less than or equal to 0.05 for taster A; r = 0.657, P less than or equal to 0.01 for taster B; and r = 0.686, P less than or equal to 0.01 for both tasters' overall ranking). Similar regressions against black tea theaflavins, thearubigin content, liquor brightness and total colour were not significant. The results suggest that the green leaf chemical components, (-)epicatechin gallate, (-)epigallocatechin gallate and caffeine could be used as quality potential indicators during clonal selection and propagation.
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