All rights reserved.
All wines contain at least some small amount of sulfites.
They are a natural result of the same fermentation process that turns grape juice into alcohol. Even wines that have not had any sulfites added during the winemaking process contain some amount of sulfites. It keeps down the activities of native yeast and bacteria and preserves the freshness of the wine. Modern technology has allowed the use of significantly less sulfur than was used in the past but some is necessary to make a stable wine. Regulations in the United States require that domestic and imported wines carry warning labels if they have sulfites in excess of 10 parts per million.