Astringency

Astringency is one of the most important sensory characteristics in tea evaluation, yet it is frequently confused with bitterness. Bitterness is a taste detected by taste buds; astringency is a tactile sensation — a physical drying and tightening of the oral tissues caused by polyphenolic compounds (tannins) precipitating salivary proteins. The two often co-occur in tea but are distinct phenomena. Moderate, well-integrated astringency is desirable — it provides structure and palate-cleansing ability, much like tannins in red wine. This is why strongly astringent black teas (Assam, Ceylon) pair excellently with rich foods: the astringency scrubs fat from the palate between bites. Excessive or harsh astringency indicates over-brewing (too hot, too long) or low-quality tea. The type of astringency matters: catechin-driven astringency (green tea) feels bright and quick; theaflavin-driven astringency (black tea) feels broader and slower; aged tea astringency (old pu-erh) is almost entirely absent, replaced by smoothness. Tea evaluation professionals describe astringency as "brisk" (positive), "drying" (neutral), or "harsh" (negative).