Young raw Pu-erh often tastes bitter or astringent because its fresh leaves contain naturally occurring compounds such as catechins and other polyphenols, while the tea has not yet undergone the long-term transformation associated with aged Pu-erh. Bitterness and astringency are not automatically signs of poor quality; their intensity, balance, and aftertaste matter more.
Gongfu tea is usually bitter because the leaves are being extracted too aggressively—most commonly from a combination of too much tea, too long an infusion, excessively hot water for that particular tea, or unsuitable water.
