Sulfites and WineWhat Are Sulfites?
Sulfites are a naturally occurring compound that nature uses to prevent microbial growth. They are found on grapes, onions, garlic, and on many other growing plants. No wine can ever be "sulfite free", since they come in with the grapes.
The easy way to see if sulfites are a problem are for you is to eat a food high in natural sulfites - say, dried apricots. On average, 2oz of dried apricots have 10 times the sulfites as a glass of wine does. If you eat those apricots and have a reaction, now you know it's time to talk with a doctor.
Why Add Sulfites to Wine?
Winemakers have been adding additional sulfites to wines for millenia. The Greeks and Romans used sulfur candles to sterilize their wine barrels and amphorae. Sulfur protects damage to the wine by oxygen, and again helps prevent organisms from growing in the wine. This allows the wine to "last longer" too, which lets it age and develop all of those complex flavors we all love and enjoy so much. If you didn't add sulfites, the wine would turn into vinegar in a matter of months.
What's the Problem with Sulfites?
Sulfite allergies are a problem for some wine drinkers, just like some people are very allergic to peanuts. Humans can be allergic to just about anything. For people who have a sulfite sensitivity, the sulfites can lead to serious headaches. White wines have more sulfites than red wines, so this can be a way to determine if sulfites might be the problem. Sulfites, used improperly, can also give a rotten-egg smell to a wine. There is no consensus on any other problems caused by sulfites.
What's Different about a Wine Without Added Sulfites?
A wine without added sulfites might be drinkable by those with only a mild allergy to sulfites. These people might be OK with the "natural sulfites" but have a reaction when they have a wine with "added in sulfites". Remember that a wine without added sulfites cannot last long, however. Usually 18 months is the longest a sulfite-free wine would survive. This includes the time the wine spent at the winery, at the wine shop as well as in your basement! So while no-sulfites-added is fine for "drink young" wines like Chardonnay, it would not be good for a "drink in a year" wine like a Cabernet Sauvignon.
How does a Winery Create Wine Without Adding Sulfites?
Again, this is only for wines that will be drunk very quickly. The winery has to make sure to warn people to drink it soon, so they do not get vinegar when they open the bottle. The second issue is that sulfites help to keep wild organisms in the winery from harming the wine. So if a winery isn't going to use sulfites, they have to make sure their winery is *super* clean and sterile.
So the trick is for the winery to prevent contamination from occurring, without using additional sulfites to do this. Some use a layer of carbon dioxide on the wine to kill off oxygen-dependant microbes. Nitrogen gas is used during bottling, for the same reason. Also, sterile filtration is an important step. All equipment involved - tanks, barrels, pipes, must be kept perfectly clean at all times. This is a lengthy and meticulous process for a winery to follow. The bottle of wine then needs to be stored chilled and on its side.
How Free is Sulfite Free?
The ATF, the governing body for wineries in the US, allows wineries to call a wine sulfite free when the levels of sulfites are under 10 parts per million (ppm). This is much lower than many sulfite-rich foods like dried apricots.
If you feel you have a sensitivity to wine, and you have ruled out sulfites, it might be good for you to read up on -
Cogeners and wine - Cheap Wine Headaches
European Wines Cause Fewer Headaches?
Histamines and wine
Tannins and wine
Sulfates vs Sulfites
Wine Glossary Main Listing
S Glossary Words
Many thanks to Dr. Kristina Lazzari and Dr. Tony Lazzari at the Cape Cod Winery for their assistance with this article.
Caveat: I am not a doctor ... for detailed answers about how wine will affect you personally given your medical condition and lifestyle, contact your family physician