Kuwei
Definition
The Chinese tasting term for a meaningful bitterness in tea, especially the kind that converts cleanly into returning sweetness. Distinguished from harsh or stale bitterness, kuwei is considered a positive quality.
Why it matters
Kuwei, literally bitter taste, names the bitter dimension of a tea in Chinese tasting vocabulary. Crucially, it does not carry the negative connotations of bitter in English. A clean, transparent kuwei that quickly resolves into huigan is widely regarded as a sign of high-quality leaf, particularly in young sheng pu-erh, dancong, and certain greens. Kuwei comes principally from catechins, caffeine, and certain glycosides; how the leaf and processing distribute these compounds, and how the brewer manages temperature and time, determines whether bitterness reads as crisp and alive or rough and harsh. In practice, tasters distinguish kuwei from se (astringency), and from sour or harsh off-notes that indicate damage or poor storage. A great young sheng can be deeply bitter at first sip and yet leave only sweetness in the throat seconds later.