Contains sulfites is often written in the back of a bottle.
But what does it really mean?
Sulfur Dioxide (SO2) is a preservative permitted in winemaking.
No wine is sulfite-free, as they are a natural product of fermentation.
First used by Romans who burned sulfur candles (fumigation) to keep bugs off their wine.
Today we know that sulfites have antibiotic and antioxidant action.
Ultimately they avoid wine turning into vinegar.
They also prevent browning in wine and dried fruit such apricots and figs.
Products keep the original color appearance, and avoid rotting.
In Europe are sulfites known as E220 as food preservatives in baked goods, condiments, potatoes and shrimp.
Good news: sulfites are not responsible for your headache!
1% of the US population is sensitive to sulfites, but symptoms do not include headaches.
Possible causes may be allergy to tannins, histamines, proteins or alcohol.
By the way, red wine contains less sulfites than white wine, because tannins are natural preservatives.
White dessert wines contain most sulfur, followed by white medium sweet wines. More sugar needs more protection.