Sulfite-free does exist

[TimP]

I am glad there is some interest in this topic. Wine fermentation does create some amount of naturally occuring sulfites, but they dissipate or "blow off" during oak storage and normal aging. Most wineries add sulfites at several times in the winemaking process.
Second point--the lab that tests our wines declared that they found 0 ppm in our wines, and their testing capabilities are sensitive down to 1 ppm. Kcwhippet is correct in that TTB regs allow a tiny concentration to still be labeled "no detectable sulfites," but ours really have zero. I fully admit that 1 ppm versus 9ppm is a tiny, tiny difference. Even 9ppm would affect hardly anyone.
Many wines from rural, household winemakers have 0 ppm because they simply do not add any at any time. A certain concentration is produced naturally, but it all (or most) dissipates by bottling time.