Wine is often blamed for health complaints – everything from migraines to asthma and scratchy throats. But does all wines contain sulphites, and why does my wine have to contain it?
The truth is that all wines contain sulphites, generally in the form of sulphur dioxide, which in high quantities smells like a freshly struck match. It is only when levels rise significantly that one finds allergic reactions.
Although this compound is found naturally in wine, most winemakers add an additional dose to preserve the wine from oxidation and prevent microbial contamination.
Some winemakers experiment with alternative winemaking options to limit their need for preservatives, including treating the wine with ultraviolet light, for instance, or making a wine with minimal interference. But in general these wines have a much shorter shelf life.
As a rule of thumb, remember that red wines generally have the lowest sulphite content because naturally occurring tannins also act as a preservative. White wines are more at risk for spoilage and therefore need more protection, while the high sugar content of fortified wine also means a high level of protection from sulphites.
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