Aeration versus Oxidation

• When a bottle of wine is first opened, particularly a mature red that has seen some aging, air is a good thing. It hits the alcohol and starts the process of evaporation, which releases the undesirable qualities of wine such as sulfites and ethanol. This evaporation is also what brings the wine’s aroma to your nose. Prolonged exposure to air, known as oxidation, has the undesired effect of flattening a wine, which is why you put the cork back in the bottle when saving it for later. With most wines, you would have to swirl non-stop for several hours before oxidation would occur.

The Type of Wine

• The heavier and fuller bodied the wine, the more it benefits from aeration, and the longer it can be exposed to air before losing its flavor. Swirling and pouring your wine from the bottle to glass will aerate your wine, but some vintages such as aged reds benefit from additional aeration. “Breathing” a wine means uncorking the bottle and allowing it to sit for a time before pouring; “decanting” is when a wine is poured out of its bottle and into a separate, clear container to allow for a separation from sediment and even more mixing of the wine with oxygen.

When to Swirl

• Both red and white wines benefit from swirling before tasting. Generally speaking, when you swirl a young white such as a pinot grigio, you are looking for the “aroma"; when swirling a mature red that has been aged, you are experiencing a “bouquet.” When drinking wine at a casual function served in plastic cups, there is no need for the ceremony of the swirl and taste. If you have ordered a bottle of wine in a restaurant, the server will most likely pour a small amount of wine into your glass. Even if you are ordering a second bottle of the same wine, it still needs to be swirled and tasted to make sure the bottle hasn’t gone bad.

The Fine Points of the Swirl

• The safest way to swirl your wine before tasting is to keep the glass steady on the table. Hold the stem with your thumb and forefinger, and gently rotate your wrist. Most right-handed people prefer to swirl in a counter clockwise motion, while lefties tend to favor the opposite direction. It really doesn’t matter which way you go as long as the wine rises up along the edges of the glass. This will allow you to appreciate the color of the wine, and to see its “legs” drip down the sides of the glass. And then, finally, after seeing, swirling and smelling, comes the moment you’ve been waiting for: the taste.