Many people are unsure of what it means when they look at a wine label and it reads, "Contains Sulfites." Often, wine drinkers may ask questions like, "What is a sulfite?", "What role does a sulfite have in my wine?", or "Is it natural or did someone add it?" According to one of our most popular wine books available for purchase on our site, Wine For Dummies (4th Ed.), the term "sulfites" specifically refers to the compound sulfur dioxide. Sulfur dioxide occurs on its own in small amounts during the process of fermentation, but wine makers often add additional amounts of it to their wines. The amount added depends on the individual wine maker and wine type; some wine makers believe the less sulfur dioxide added, the better, while others are more liberal with their sulfur dioxide addition, depending on the needs of a given wine.
Sulfur dioxide serves several functions in wine, including acting as an antimicrobial against both bacteria and yeast. This helps prevent the wine from turning into vinegar, as well as keeping the more sugary wines from further fermentation past a certain point to maintain their sweetness. It also acts as an antioxidant, meaning it can help keep the wine fresh and sequestered from oxygen molecules until the wine is ready to be consumed. The amount of sulfur dioxide in a wine is measured as a unit of parts per million, or ppm, and the total quantity of sulfites in any given wine can be anywhere from 30 to 150 ppm. Typically, only 10 to 20 ppm occur naturally as a result of fermentation, so you can see that some wines have quite a bit of sulfur dioxide added, while others may have relatively little added beyond what the fermentation process naturally produces. Sweeter wines and white wines tend to have more, while dry wines and red wines tend to have less.
Now that you have a better understanding of the chemistry of your wine, relax and enjoy a glass of your favorite with one of our custom engraved wine glasses. Whether you like white or red, sweet or dry, ice cold or cool, we've got the glasses you need to get the most out of your favorite wine!