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Is SO2 in wine bad for you ?

· Wine Culture

If you look carefully at a wine label, you will often find the name of sulfur dioxide (SO2) in its components, a colorless gas also commonly called "sulfites".

Many consumers are confused about it, and research shows that it can be harmful to the human body. Today, let us reveal the mystery of SO2 in wine.

Why there is SO2 in wine

SO2 plays a quite important role in the winemaking process.

SO2 is used in winemaking as a preservative because of its anti-microbial properties. These properties inhibit wild and spoilage yeasts and unwanted bacteria. Besides, SO2 will be added to the wine during the bottling process, to stabilize it over time (as there is still some sugar and bacteria left in the wine).

SO2 is also an "antioxidant", a property also needed in the wine industry. During the winemaking and storage processes, SO2 blocks the oxygen, thus avoiding the oxidation of wine and ensuring that the wine preserves its fruity flavours and freshness.

Sulfur dioxide is also used as acleaning agent for barrels and winery facilities.

Adding SO2 in wine, is that really OK ?

Although we now know that SO2 is important to preserve wine, it is often said that SO2 is regarded as a noxious gas, causing symptoms like hives or headaches to some people.

However, estimates show that very few people are sensitive to SO2 (0.05 to 1 percent of the population, or up to 5% of people who have asthma). Also, to show side effects, the quantity of SO2 consumed must be really high, definitely more than a few glasses of wine.

Dried fruits have sometimes sulfite levels as high as 630 ppm. So if you can eat dried apricot and mangoes without problems, then you can handle the sulfites in wine.

Still, each country has strict rules to limit the amount of SO2 depending on the type of wine.

Indeed, sweet wines contain more SO2 as there are more fragile than dry wines.

So if SO2 in wine is limited and and regulated, why do you sometimes have headaches after drinking ?

This is mostly because wine dehydrates you very quickly, which causes headaches.

Are there wines without SO2 ?

First of all, it is important to remind that SO2 is naturally created during the fermentation process. Therefore, there is no such thing as a wine without any sulfites.

Wines labelled “without sulfites” actually mean that no SO2 was added to the wine during its making. This type of wine typically falls in the “Organic” or “natural” categories of wine.

This new label was created in France in March 2020 and states "without added sulfites"

Many winemakers are adopting organic or natural methods, but the resulting wine is typically more fragile and is more subject to oxidation or unwanted second fermentation once bottled.

In the end, the most important is that winemakers grow quality grapes to produce quality wines, with the least amount of additives possible. And a bit of SO2 will definitely help to preserve quality without hurting consumers.

After reading this article, we hope you can make up your mind about SO2. Anyways, drink in moderation and drink one glass of water for every glass of wine to avoid headaches !

Founded in 2018 by Matthieu Ventelon, Hedonia is the first institution in China combining professional Wine and Etiquette expertise in the same training offer.

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