Tannin Myths and Methods

From modern wine chemistry labs to your home winery — what is known about tannins and how can winemakers control their impact on their wine? Research is debunking many widely-held beliefs about tannins, but there are still proven ways to get the structure you desire without excessive bitterness or astringency. Here’s a quick summary of the conventional tannin wisdom of a few years ago, still in wide circulation among both commercial and home winemakers: • Grape skin tannins are your friends,  seed tannins are your enemies. • After fermentation, as wines age,  tannins form themselves into longer  and longer chains. • Those longer chains are softer and less  astringent in the mouth. • Eventually, with really mature wines, the  chains get so long that they  precipitate out of the wine entirely. Alas, every one of these assertions is at best wildly over-simplified, if not dead wrong. Research in the past decade has undermined most of the traditional tannin myths, opening a window on a vastly more complex world of phenolic interactions than previously thought. Instead of these simple “truths,” phenolic