<P> An astringent (occasional alternative: adstringent) substance is a chemical compound that tends to shrink or constrict body tissues . The word "astringent" derives from Latin adstringere, meaning "to bind fast". Two common examples are calamine lotion and witch hazel . Another example is yerba mansa, a native plant of California . </P> <P> Astringency is also the dry, puckering mouthfeel caused by tannins that are commonly found in many fruits, especially when they are unripe . This helps to ward off predators so that the seeds within the fruit can reach maturity . Some extreme examples of astringency even in ripe fruits include blackthorn (sloe berries), Aronia chokeberry, chokecherry, bird cherry, quince and persimmon fruits, and banana skins . Many citrus fruits such as lemon also have a mild to moderate astringency . The tannins (which are types of polyphenols) bind the salivary proteins, causing them to precipitate or aggregate and lead to a rough "sandpapery" or dry sensation in the mouth . Tannins are found in some red wines and teas . A small amount of astringency is expected in some wines, especially young red wines made from grapes such as cabernet sauvignon and merlot . </P> <P> Astringents in medicine cause constriction or contraction of mucous membranes or exposed tissues and are often used internally to check discharge of blood serum or mucous secretions . This can happen with a sore throat, hemorrhages, diarrhea, or with peptic ulcers . Externally applied astringents, which cause mild coagulation of skin proteins, dry, harden, and protect the skin . People with acne are often advised to use astringents if they have oily skin . Mild astringent solutions are used in the relief of such minor skin irritations as those resulting from superficial cuts, allergies, insect bites, or fungal infections such as athlete's foot . </P>

What is the difference between astringent and antiseptic