How can I tell if a wine cork is real or synthetic?

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Dear Dr. Vinny,

How can I tell if a wine cork is real or synthetic?

—Jewel, Gainesville, Fla.

Dear Jewel,

You can’t tell just by looking at a bottle of wine if the cork inside is natural or synthetic, but once you remove the capsule and pull the cork, it should be pretty easy. Most synthetic corks look and feel like polyethylene—they are smooth, almost like plastic, and sometimes come in non-cork colors. Real, natural cork, which is made from the bark of cork oak trees, is lighter, woody feeling and much more squishy and spongy (with red wines especially, you’ll also probably see that wine has soaked in and stained some of the cork).

The type of closure that’s used on a bottle of wine is not an indicator of quality—that goes for natural cork, synthetic corks and screwcaps. Some vintners prefer the traditional natural cork closure; others are trying to avoid problems associated with natural cork.

If you’re interested in using less plastic in your life and are avoiding synthetic corks for that reason, there are some online databases that point out bottlings with real corks—but to be comprehensive, you’d have to contact the wineries directly to find out.

—Dr. Vinny

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