a study of the quality of a local herbal tea and volatiles of parinari ...

The difference in total theaflavin content between F. ancylantha and Lipton black tea
could be attributed to the fermentation process employed in the herbal tea processing. In
Vundakulwayo village in Karonga district, drying of the tea leaves is continued “until the
leaves turn brownish”. This allows fermentation to proceed and thearubigins increase at
the expense of theaflavins (Srilakshmi, 2003). The herbal tea had higher thearubigin
content than Lipton black while theaflavins were higher in Lipton black than in
F. ancylantha tea. According to Hara (2004), high theaflavin content usually implies
good manufacturing practices. The presence of high thearubigins in the herbal tea means
improvement in the processing of the herbal tea is necessary. Inorder to improve the
quality of this traditional tea, the fermentation time should be reduced to minimise
thearubigins and thus achieve adequate theaflavins. When compared with the content of
theaflavins in black tea (0.3 - 2.0 %) the values for Lipton black (0.48 %) and
F. ancylantha (0.37 %) are within the acceptable range of theaflavins for black teas
(Banerjee, 2005). The presence of theaflavins in Lipton green (0.22 %) means some
fermentation occurred during processing of the Lipton green tea. This is because green
tea may also contain constituents commonly found in black tea such as theaflavins and
thearubigins and therefore some oxidation and condensation of catechins occured
(Brown, 1999).
Significant (p