When you drink a red you may notice a dry sensation in your mouth that entices it to prick up with a bit of grit and maybe even leave it feeling furry. That sensation is the tannins at work. Tannin is the compound extracted from grapes skins, pips and stems and is most noticeable in red wines where there is most skin contact during winemaking and they are also found inside the skins of most fruits and vegetables too. So tannins are acidic and your mouths saliva has protein in it, so when you sip the wine they react to each other. When a wine ages, the tannins develop and become more rounded and polished and it also acts as a preservative. So you may be wondering.... 

Why do some wines have more tannin than others? 

Well... A Cabernet Sauvignon or a Shiraz will have much higher tannins than say a Pinot Noir or Sangiovese because those grape varieties have a higher acidity. When wine ages, the tannins develop and become more rounded and polished. Now, what if you have a wine where the tannins are just too much? This can be helped by getting some oxygen into the glass. Grapes ripen on the vine when exposed to oxygen and the same happens when it is in your glass. You can decant the bottle and let it sit for a while and this will open it up, this is better than just opening the bottle and letting it sit because it gets the wine moving and motivates it to work harder to open up. Red meat also helps mellow the effect of the tannins in reds and compliments it extremely well as I am sure you know. 

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