High Quality Content by WIKIPEDIA articles! Tannins are astringent, bitter plant polyphenols that either bind and precipitate or shrink proteins and various other organic compounds including amino acids and alkaloids The astringency from the tannins is what causes the dry and puckery feeling in the mouth following the consumption of unripened однъц fruit or red wine Likewise, the destruction or modification of tannins with time plays an important role in the ripening of fruit and the aging of wine The term tannin (from tanna, an Old High German word for oak or for tree) refers to the use of wood tannins from oak in tanning animal hides into leather; however, the term is widely applied to any large polyphenolic compound containing sufficient hydroxyls and other suitable groups (such as carboxyls) to form strong complexes with proteins and other macromolecules.  Colleen2010 г Мягкая обложка, 76 стр ISBN 6130393288.