What are Those Pigments?

Red wine, blueberries and petunia flowers all contain anthocyanins, the most common red plant pigments of all. Anthocyanins belong to a group of secondary plant metabolites that are called flavonoids, and are almost ubiquitously synthesized by plants in at least some tissues, particularly under stressful conditions. (Beetroot, by the way, owe their intense colour to betacyanins, a group of similar, but different, compounds). The flavonoids also include some of the pre-cursors of tannins, but more on that later…, and they are part of an even larger group of compounds thermed phenolics. All phenolics, including anthocyanins, contain at least one phenolic ring (benzene group or aromatic ring are alternative terms). Anthocyanins have three, and there are very very tiny differences in the structure of anthocyanins compared to other “neighbours” such as the yellow flavonols, that endow them with the ability to tickle our perceptions with different wavelengths (or colours).