This guide to sulfites in wine is part of our wine guide series. Learn about the subtleties of wine, how they affect wine flavor and how compounds such as sulfites can aid in preserving wine.
What are Sulfites in Wine?
The term Sulfite is used to describe a chemical compound called sulfur dioxide. This compound is common and occurs naturally not only in grapes used to make wine, but in many other fruits as well. In fact, mangos and apricots contain almost 10 times more sulfites than what is found in red wine.
Evidence of sulfite use in early winemaking has been found during excavations around ancient Rome. Indicating that the Romans discovered its fumigating properties by burning candles around their wine barrels.
Why Sulfites are used in Wine
Winemakers will commonly add additional sulfur dioxide to some wines at the beginning of fermentation in order to increase longevity of the juice. In short, sulfites are used as a preserving agent in wine, which, specifically has antioxidant, anti-browning and antimicrobial properties. Thus, helping to prevent a wine from turning into vinegar.
How much sulfur dioxide goes into a wine?
The quantity of sulfites present in wine depends on the kind grape varietals being used and what qualities a winemaker is looking to achieve with their product. For example, wines with high acidity require less sulfur dioxide, as the acid already aids in preservation.
Sidenotes: Sulfites in general have gotten a bad rap over the past few decades. In reality, they are not the cause of headaches as rumored to be from drinking red wine.
Some winemakers today include a label on their bottle saying “Contains Sulfides.” This is because a percentage of the United States population is highly allergic to the sulfur dioxide compound, especially those with asthma. Only wines that contain 10 PPM (parts per million) or more of the sulfur dioxide compound are legally required to be labeled in this manner in the US.
The short answer is no. If you have known food allergies, or find yourself overly sensitive to certain foods that contain preservatives (like many processed foods or packaged meats), you might do yourself a favor to limit your intake. The same goes for those who may be asthmatic. Just listen to what your body is telling you. Don’t use a headache as an indicator to being overly sensitive to sulfur. The reality is you probably just had too much wine, too much cheese and didn’t drink enough water. The quantity of sulfites in most wine is vanishingly small and typically will not affect most wine drinkers.