Definition - What does Sulfites mean?
Sulfites also known as sulfur dioxide (SO2) is a chemical property that is present in all wines as a result of the fermentation process. The amount present after fermentation is relatively small, and some wine makers prefer to add increased amounts of SO2 to help keep the wine sterile, control yeasts and bacteria and slow down oxidation. In recent years, some winemakers have removed these added sulfites, stating that it helps bring out the flavors of the wine.
WineFrog explains Sulfites
In winemaking, sulfites have been used for years in order to help control the more “wild” aspects of the wine and keep it sanitary for consumption. In both the U.S. and E.U., winemakers must denote the phrase “contains sulfites” on wine labels for any wine that contains SO2 ranging between 20-200 PPM. This amount could occur naturally and/or be added to the wine during fermentation. Historically, sulfites were used to maintain a wine’s freshness, but now, winemakers are attempting to make wine without sulfites.
There are pros and cons to both SO2 added and removed; whether or not to keep it or remove the sulfites depends on the winemaker. In some cases, the SO2 is necessary to keep the wine from perishing which is especially true for white wines. Some wine drinkers state that wines with added SO2 have muted and subdued flavors compared to those wines that do not have SO2. Those wines without SO2 are described as having more vibrant flavoring and complex structure. However, only experienced winemakers should attempt to remove SO2 as the wine can go uncontrolled and unruly with bacteria, yeasts and unwanted flavors. Although disputed, studies have found that where wines cause headaches in the drinker, the culprit is often the sulfite compounds and not the wine itself. Sulfites may also cause allergic reactions in some individuals.