Proanthocyanidins

Figure 1. The chemical structure of different forms of Proanthocyanidins.

Proanthocyanidins are a class of polyphenols found in many plants, such as cranberry, blueberry, and grape seeds. Proanthocyanidins are Bioflavonoids with oligomeric chemical structure (i.e. a molecule which consists of a few repeating units). Many Proanthocyanidins are oligomers of catechin and epicatechin and their gallic acid esters. More complex polyphenols, having the same polymeric building block, form the group of tannins.

For nutritional values, refer to the Codex entry for Oligomeric Proanthocyanidins.