There are many catechins in tea, especially in green tea and oolong tea. Green tea usually contains 20–30% of catechins (Engelhardt, 2010; Wang, Provan, & Helliwell, 2000), oolong tea has the similar amount
There are many catechins in tea, especially in green tea and oolong tea. Green tea usually contains 20–30% of catechins (Engelhardt, 2010; Wang, Provan, & Helliwell, 2000), oolong tea has the similar amount