Tannin is a natural substance found in plants — especially in tree bark, tea leaves, grape skins, and the skins and seeds of many fruits. Two places you meet it matter most.

Tannin Tannin（單寧）is a natural substance found in plants是一種存在於植物裡的天然物質 — especially in tree bark, tea leaves, grape skins特別是樹皮、茶葉、葡萄皮, and the skins and seeds of many fruits以及很多水果的皮和籽裡。Two places you meet it matter most有兩個你會遇到它的地方最重要。

First, leather: for thousands of years people soaked animal hides in water full of tannin from oak bark, which stopped the skin rotting and made it into leather. That is where the whole family of tan words comes from.

First, leather第一，皮革: for thousands of years幾千年來 people soaked animal hides in water full of tannin from oak bark人們把獸皮泡在充滿橡樹皮單寧的水裡, which stopped the skin rotting這樣能防止皮腐爛 and made it into leather並把它變成皮革。That is where the whole family of tan words comes from這就是tan這一整個字族的來源。

Second, drink: tannin is what makes strong black tea feel dry and rough in your mouth, and it is a word wine drinkers use constantly — a red wine "high in tannins" grips your tongue and makes your mouth feel dried out. That dry, grabbing feeling has its own name in English: astringency.

Second, drink第二，飲料: tannin is what makes strong black tea feel dry and rough in your mouth單寧就是讓濃紅茶在嘴裡感覺乾澀粗糙的原因, and it is a word wine drinkers use constantly也是喝紅酒的人常掛在嘴邊的字 — a red wine "high in tannins"一支「單寧高」的紅酒 grips your tongue會抓住你的舌頭 and makes your mouth feel dried out讓你的嘴巴感覺乾乾的。That dry, grabbing feeling那種乾澀、抓緊的感覺 has its own name in English在英文裡有自己的名字: astringency astringency（澀感）。

Tannin is also used in making ink, in some medicines, and in dyeing, and it is what turns a cut apple brown. In wine and tea talk people usually say tannins, in the plural, because there are many different tannin compounds, not one single chemical.

Tannin單寧 is also used in making ink也用在製造墨水, in some medicines一些藥物, and in dyeing還有染色上, and it is what turns a cut apple brown而且它就是讓切開的蘋果變褐色的原因。In wine and tea talk在講紅酒和茶的時候 people usually say tannins, in the plural大家通常說複數的tannins, because there are many different tannin compounds因為單寧其實有很多不同的化合物, not one single chemical不是單一一種化學物質。

Notice that tannin is not really about taste — it is about how your mouth feels, which is why beginners often struggle to find the word for it.

Notice that tannin is not really about taste要注意，單寧其實跟味道沒什麼關係 — it is about how your mouth feels它講的是嘴巴的觸感, which is why beginners often struggle to find the word for it這就是為什麼初學者常常找不到詞來形容它。