Tannin Chemistry in Wine

It all starts with phenol. The tannins in wine make up one of the subgroups in a larger chemical family known as polyphenols. Those, in turn, are made up of phenol-derived molecules and additional carbon, hydrogen and oxygen atoms. While a winemaker does not need to know the chemistry of polyphenols and tannins to make good wine, some basic knowledge can help drive winemaking decisions that may improve the outcome of any given vintage. So, if you like a bit of technical illumination along with your homemade wine, follow us here into the magical world of these complex and fascinating chemical compounds. Benzene and Phenol Phenol can be viewed in terms of its derivation from the benzene ring. The chemistry and reactions of benzene, formula C6H6, were well understood in the 19th Century. Its structure, however, eluded researchers of the time until August Kekulé had a dream of a snake biting its own tail. That gave him the idea that perhaps benzene was a ring of six carbon atoms, each with one attached hydrogen atom. At the time, the numbers