Moreover, tea is generally consumed in the
form of green, black, oolong and white tea (Pettigrew, 2004). The
processingmethods for production of each type of tea are greatly different.
Different types of tea are categorized based on fermentation degree
(oxidation degree of polyphenols in fresh tea leaves); fermentation degree
of green tea is 0 (unfermented), fermentation degree of black tea is
100% (full fermentation) and fermentation degrees of white tea and
oolong tea are about 20–30% and 30–60% respectively (Engelhardt,
2010; Harbowy & Balentine, 1997). Consequently, the antioxidant activities
among them are dissimilar.