Answers to frequently asked questions about sulfites in wine What are sulfites? Sulfite describes forms of sulfur (sulfur dioxide, for example, or sodium sulfite or sulfate) that are present in wine. Sulfur is a nonmetallic element that is very common in nature and is, in fact, essential to life itself. Sulfur has been used since ancient times for many purposes, including the cleaning of wine receptacles by both Egyptians and Romans. Sulfur has been a food additive since the 17th century and approved for such in the United States as long ago as the 1800s. Sulfites are currently used [...]