鞣质又称单宁、鞣酸,是中草药中普遍存在的一类成分。如五倍子、地榆、虎仗等中草药中存在大量鞣质。将植物某些部位切开,如暴露于空气中渐渐由浅色变为红棕色或嚐之有涩味,都证明有鞣质的存在。绝大部分的中草药煎出液呈红棕色,一般也是由于含有鞣质及其缩合物之故。 Tannin, also known as tannin and tannin, is a common ingredient in Chinese herbal medicine. Such as gall, earthworm, tiger locust and other Chinese herbal medicine in a large number of tannins. Cutting some parts of the plant, such as exposure to the air gradually changing from light to reddish-brown or tasted astringent taste, has proven the existence of tannins. Most Chinese herbal medicines have a reddish-brown liquid, which is generally due to the presence of tannins and their condensates.