Swirling wine in a glass aerates a wine, “opens” its gifts, and releases its aroma. Aromatic esters, ethers, and aldehydes (the so-called volatile compounds) are exposed to more oxygen, intensifying the aromas and heightening the so-called “nose” of the wine. In addition, swirling allows more oxygen to react with the tannins, causing the wine to mellow.
When swirling, always hold the glass by the stem, and after giving the wine a few swirls, stick your nose into the glass and take a deep sniff. No need to repeat this action for a few minutes as the olfactory system takes a little time to recover.
The technique of swirling wine involves a gentle rotation with the wrist in a counterclockwise or clockwise direction, and is most easily learned with the glass on a table. I emphasize gently; if you are too vigorous, you may embarrassingly slosh wine over the sides of the glass onto your hand, exposing you as a novice. The French believe that when you swirl a glass clockwise, the wine releases fruit aromas. They also believe counterclockwise swirling is bad luck, and that when you swirl to the left, earthy scents fill the glass. These are likely fables.
Once you’re accustomed to doing this successfully, you will find yourself swirling everything in a glass. Just remember never to swirl sparkling wine or Champagne as it will dissipate the bubbles and the wine will go flat more quickly.
Riedel Sommeliers Cabernet/Merlot/Bourdeaux Wine Glass: wineenthusiast.com