Proanthocyanidins are oligomeric flavonoids, mainly begin in grapes. They are dimers (see picture) or oligomers of catechin and epicatechin and their gallic acid esters.
Proanthocyanidins are mainly begin in the derma and seeds of grapes. They are aswell present in red wine. During the assembly of red wine, the abstract is larboard to agitate with the seeds and banknote during a few days. During this beverage process, the formed booze will abstract the proanthocyanidins from the seeds and skins. Other affluent sources are cocoa, apples, peanuts, almonds, cranberries, blueberries and case of the amphibian pine.
Many plants aftermath proanthocyanidins in their fruits, bark, leaves and seeds to assure them from predation. Proanthocyanidins accord the archetypal acidity to foods such as wine and teas.