The preservative most commonly used in conventional winemaking is sulphur dioxide (SO2). This Sulphite contains antibacterial properties that lengthens the life of the wine.
Whilst it tends to be harmless to most consumers some people can suffer allergic reactions, including rash, hives, cramps and blotchy skin. If you have a lack of certain enzymes, that are needed to break down sulphites in the body, you should not consume conventional wine.
Wine made in Europe can contain up to 210 PPM (parts per million) of sulphites, but any wine having over 10 PPM must include “contains sulphites” on the label. Therefore, any bottle of wine from Europe that states “contains sulphites” could have anywhere between 10 and 210 PPM of sulphates. The problem is you simply don’t know the exact amount.
A wine from America can contain up to 350 PPM!
If a wine producer is certified as being organic, their wine will include the logo of any one of a few regulating bodies. The two main regulators are DEMETER and ECOCERT.
The level of sulphites allowed in organic wine, is much lower than allowed in conventional wines. The lower the level of sulphates the more natural the wine, resulting in health and ecological benefits.