Aerating wine involves the simple process of exposing it to air before serving. Accomplish wine aeration simply opening a bottle and letting it sit for a half an hour to 45 minutes before serving. Pouring wine into a decanter represents a quicker way to aerate it. A number of benefits accrue with wine aeration.
Aerating wine triggers both oxidation and evaporation. Oxidation is what causes an apple to turn brown while evaporation is the process through which a liquid changes to a vapor. Aeration impacts some of the hundreds of different compounds that comprise wine.
Through the aeration process, some of the less desirable and more volatile compounds contained in wine evaporate. These less desirable elements tend to evaporate faster than more desirable ones, resulting in an enhancement of the aroma and flavor of the wine. For example, some wines have a trace scent of ethanol when opened. Through aeration, the smell is eliminated rather quickly, rendering the wine aroma more pleasant. In addition, the flavor generally improves.
If left to aerate too long, oxidation takes effect. Oxidation potentially flattens the aroma as well as the flavor of wine. A denser wine aerates for a longer period of time before oxidation begins to have a negative impact on the aroma and flavor.
Making a practice of decanting wine represents the easiest and surest way to optimize aroma and flavor through aeration. If a host elects not to aerate wine before serving, a common technique involves swirling the wine in the glass once served. Swirling is not to be overdone. Effective aeration requires about a minute's worth of in-glass swirling.