Sulfites in Wine: What They Are and Whether They Matter

Wed, 22 Jul 2026 00:00:00 +0000

Flip over any bottle and there it is: contains sulfites. It reads like a warning, half the internet blames it for headaches, and an entire category of natural wine markets itself on leaving them out. So what are sulfites actually doing in your wine, and should you care? Short answer: they are the most misunderstood two words on the label.

What Sulfites Actually Do

Sulfites are compounds of sulfur dioxide (SO2), and they are wine’s bodyguard. They do two jobs: they block oxidation, which keeps white wine fresh instead of brown and flat, and they suppress rogue bacteria and yeasts that would otherwise turn your Chablis into something closer to vinegar. Without them, most wine could not survive shipping, shelf time or a warm boot of a car. Winemakers have burned sulfur in barrels since Roman times; this is not a modern industrial trick. Sulfur’s role in the winery is standard territory in the WSET Level 2 grape growing and winemaking quiz, incidentally.

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Sulfites in Wine: What They Are and Whether They Matter

What Sulfites Actually Do