What you need to know about Sulphites in Wine

All wines contain a degree of sulphur dioxide, which is commonly known as 'sulphites'.

Sulphur is found in different levels depending on the origin of the wine. Quite often, ‘cheap’ wine is considered to have a lot of sulphur content, which is effectively a chemical used to treat wine making it easier to produce.

Why does it matter about Sulphites in wine?

Taste: Sulphites in wine can affect the taste. While other chemicals and treatments may be used to cover this up, the taste of these are rather unpleasant, often detectable at very low concentrations.

Health: Sulphur dioxide can cause potentially fatal reactions to those with allergies. Not only can allergic reactions come up after consuming sulphites, but a classic ‘hangover’ will be worse if you have been consuming a high amount of alcohol that contains sulphites.

Principle: Adding sulphur dioxide breaks the principle of natural wine. Sulphites are not a natural product of wine and are added to give it a longer life, alter taste and essentially make wine more profitable for the producer. Picking up a bottle of low sulphite wine is your best move to avoid these issues.

How much is too much?

This depends on the wine type, sensitivity of the taster and ratio between free and bound sulphur dioxide in the wine.

Only a percentage of the S02 added to wine will be effective as an anti oxidant, with the majority of the remaining being completely unbeneficial. The part lost into the wine is said to be bound, with the active part to be free. A good winemaker will attempt to get the highest proportion of free sulphur to be bound.

Sulphur levels in different wine types

Red Wines: Contains anti-oxidants acquired from their skin and sterns during fermentation, meaning they don’t need much added sulphur dioxide.

White Wine and Rose: Do not contain natural anti-oxidants because they are not left in contact with skins after crushing. This leads to higher levels of sulphur in these wines.

Sweet Wines: These wines get the biggest doses because sugar combines a high proportion of S02. These wines are known to contain the highest levels.

Sensitivity to sulphites

Many people are unsure what exactly sulphites taste like. To most, sulphur can be detected in water at around 11 mg/l. When in wine, it usually cannot be obviously detected to the average wine drinker, although those accustomed to wine tasting may detect it at around 20-30 mg/l.

For most, they will not have tried a ‘natural wine’, so will not be able to personally tell the level of sulphur content.

What are the health implications of sulphur in wine?

Regular consumption of conventional wine will mean you are probably exceeding the RDA of sulphur dioxide by a large amount. More specifically, sulphur dioxide can cause allergic reactions in some people, with those with asthma often being affected. Sulphites contribute heavily to hangovers, so if you don’t fancy having a full day recovering from a night out, then avoid sulphites!