Why do some winemakers use “used” oak barrels?

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Dear Dr. Vinny,
Why do some winemakers use “used” oak barrels?
—Chris, St. Petersburg, Fla.
Dear Chris,
It’s easy to think of oak barrels as a metaphorical spice rack when making wine. New barrels have intense aromas, and can impart cedar, vanilla and, yes, plenty of spice notes when a wine is aged in them. New barrels will impart the strongest aromas and flavors to a wine, and each time a barrel is used, that influence dissipates a bit. After about three or four uses, the barrels are considered “neutral.”
Neutral barrels are still useful to winemakers—wine can be aged in them before bottling, but neutral barrels won’t add a new barrel’s influence of flavors and aromas. Barrels are not only used for flavors, they can also help with a wine’s texture and mouthfeel, since they allow small amounts of oxygen to interact with the wine, which can soften tannins. An older or neutral barrel will do this without adding those flavors typically associated with aging in new barrels.
I see plenty of winemakers using neutral barrels to get richer, creamier textures from wines. Some winemakers use a mix of new and neutral barrels, or different types, sizes and toasts of the barrels to get the style they are aiming for. Others have a barrel program that relies on one format or another. Keep in mind that a new barrel can cost upwards of $1,000, so getting some extra use out of a barrel—even if it’s for storage—can be very desirable.
—Dr. Vinny