what are sulfites in wine

Sulfites are a group of chemical compounds found naturally in some foods and added to others as a food preservative. They are also widely used in winemaking to maintain the flavor and freshness of wine. Sulfites are produced as a byproduct of yeast metabolism during fermentation, and they help prevent oxidation, minimize bacterial growth, and maintain the desired color of wine. All wines, whether they have added sulfites or not, contain sulfites. The sulfite content in wine varies, but most wines contain about 80 parts per million (ppm) of sulfites, which is lower than many processed foods. Sulfites are generally safe for most people to consume, but some individuals with sulfite sensitivity may experience adverse side effects such as headaches, hives, or difficulty breathing. In the United States, wines that contain 10 or more ppm of sulfites must state on the label that they contain sulfites, and wines labeled as organic cannot have added sulfites.