What exactly does aeration do to a wine?

Ask Dr Vinny

Hello there! I'm Dr. Vinifera, but you can call me Vinny. Ask me your toughest wine questions, from the fine points of etiquette to the science of winemaking. And don't worry, I'm no wine snob—you can also ask me those "dumb questions" you're too embarrased to ask your wine geek friends! I hope you find my answers educational, empowering and even amusing. And don't forget to check out my most asked questions and my full archives for all my Q&A classics.

Dear Dr. Vinny,

What is the science behind the aeration of wine? What does air do to a wine? Why is it if a wine is closed and then you put air though it (via a funnel of some type) that it can release the aromas and flavors of the wine?

—Heidi Y., Grande Prairie, Alberta

Dear Heidi,

Exposing wine to air does two things: it triggers oxidation and evaporation. Oxidation is what makes an apple turn brown after its skin is broken, and evaporation is the process of liquid turning into vapor. Wine is made up of hundreds of compounds, and with aeration, usually the volatile undesirable compounds will evaporate faster than the desirable, aromatic and flavorful ones.

There are a few particular compounds that are reduced with aeration, such as sulfites, which are added to wine to prevent oxidation and microbial activity but can smell like burnt matchsticks, and sulfides, which are naturally occurring but can remind you of rotten eggs or onionskins. Ethanol is also a highly volatile compound, and a wine that smells too much like rubbing alcohol when you first open it might lose the ethanol note and become more expressive with some aeration.

You mention funnels as a way to aerate wine, but just opening a bottle and pouring a glass will also provide aeration, as will swirling your glass of wine. For more extreme aeration, decanting a wine works well too. After a while, aerated wines begin to oxidize, and the flavors and aromas will flatten out. The more dense and concentrated a wine is, the more it will benefit from aeration and the longer it can go before beginning to fade. On the other hand, you probably don’t want to aerate delicate older wines for long, as you can miss out on their unique aromas, but they’re often decanted to remove sediment.

—Dr. Vinny

How to Taste Serving Wine Decanting Ask Dr. Vinny

More In Dr. Vinny

Is it OK to brush my teeth before tasting wine? Does toothpaste change the way wine tastes?

Wine Spectator's resident wine expert Dr. Vinny explains why brushing your teeth and wine …

Sep 26, 2022

What’s the difference between Hermitage and Ermitage? Are they the same wine?

Wine Spectator's expert Dr. Vinny explains what the H is going on with Hermitage vs. …

Sep 19, 2022

When traveling, are any wines more or less susceptible to bottle shock than others?

Wine Spectator's expert Dr. Vinny explains the phenomenon of "bottle shock" and how to …

Sep 12, 2022

What’s the best way to remove a crumbly wine cork? I’ve tried everything!

Wine Spectator's expert Dr. Vinny offers tips for extracting crumbly corks, and how to …

Sep 7, 2022

What’s the difference between Petite Sirah and Syrah?

Wine Spectator's expert Dr. Vinny explains that Syrah and Petite Sirah have quite a bit in …

Aug 29, 2022

I have about 50 bottles of wine. Should I buy a wine fridge?

Wine Spectator's expert Dr. Vinny offers advice for when to upgrade your wine storage at …

Aug 22, 2022