Sulphites in Wine

Sulphites in Wine

In simple terms, sulphites are a group of compounds that contain sulphur. They occur naturally in some foods and beverages, including wine and have been used for centuries as a preservative, helping to prevent spoilage and maintain the freshness of food and drinks.

Naturally occurring sulphites in wine…

Sulphites occur naturally in grapes and are a byproduct of fermentation, they are also produced by some strains of yeast during the fermentation process. Therefore, even wines labelled as ‘no added sulphites’ or ‘sulphite free’ may still contain trace amounts of naturally occurring sulphites.

The levels of naturally occurring sulphites in wine can vary depending on factors such as the type of grapes used, the region where the grapes were grown and the winemaking process itself. Generally, red wines tend to contain lower levels than white because red wines contain natural antioxidants or tannins, which can reduce the need for additional sulphites, whilst sweet wines contain significantly more.

It’s worth noting that while naturally occurring sulphites are present in all wines, they are typically at much lower levels than those added by winemakers.

Positive effects of added sulphites…

Winemakers have been adding sulphur dioxide to wine since the 1800s because it serves several important purposes in the winemaking process:

Preservation: Sulphites are highly effective at preventing oxidation and microbial spoilage, helping to maintain the wine's flavour and quality over time.

Antioxidant Properties: They act as antioxidants, which means they help protect the wine from damage caused by exposure to oxygen, crucial for preserving the wine’s colour, aroma and flavour.

Stabilization: Sulphites aid in the stabilisation of the wine's chemical composition, preventing undesirable reactions in its’ colour and flavour compounds.

Fermentation Control: In some cases, sulphites are used to control the fermentation process by inhibiting the growth of unwanted wild yeasts or bacteria.

Consistency: Adding sulphites ensures each bottle of wine from a given batch or vintage has a consistent taste profile, important for maintaining the reputation and quality of a specific wine label or brand.

Reducing Sulphur Compounds: Paradoxically, controlled use of sulphites can actually help reduce the formation of unwanted sulphur compounds during fermentation.

Enhancing Ageability: Wines destined for aging are often treated with sulphites to ensure they have the stability to evolve and mature gracefully over time.

Food Safety Regulations: In many countries, including the United States and the European Union, regulations require wines to be labelled with the statement ‘Contains Sulphites’ if they contain more than a certain threshold level, typically 10 parts per million (ppm). This labelling is an important aspect of food safety regulation.

Potential negative effects…

Whilst the positive effects of adding sulphites to wine are clear to see in terms of preservation and stabilisation, for some individuals they can have negative effects, such as:

Allergic Reactions: Some people are sensitive or allergic to sulphites. Symptoms can include skin rashes, itching, hives, difficulty breathing, wheezing, and in severe cases, anaphylaxis. It's important for individuals with known sulphite sensitivities to avoid wines with high sulphite levels.

Respiratory Issues: For individuals with asthma, sulphites can trigger asthma symptoms or exacerbate existing respiratory conditions. Inhaling sulphite-containing fumes, which can be released when opening a bottle of wine, can be problematic for sensitive individuals.

Headaches: While sulphites are often blamed for causing wine-induced headaches, there isn't strong scientific evidence to support this claim. Most headaches attributed to wine consumption are more likely due to other compounds such as histamines, tannins, or simply the alcohol itself.

Digestive Discomfort: In rare cases, individuals with sensitive digestive systems may experience discomfort after consuming wines with high sulphite levels. This can include symptoms like nausea, stomach cramps, or diarrhoea.

Reduction in Wine Aromas and Flavours: In excess, sulphites can actually impair the aromas and flavours of a wine. This is why winemakers carefully control and monitor sulphite levels to avoid overuse.

Contribution to Hangovers: While sulphites are not a primary cause of hangovers, consuming wines with high sulphite levels may contribute to overall discomfort when combined with other factors like dehydration and alcohol metabolism byproducts.

On balance…

It’s worth emphasising that the majority of people do not experience any adverse effects from consuming sulphites in wine. The threshold for sulphite sensitivity is relatively low, accounting for only 1% of people, so most individuals can safely consume wine with moderate levels of sulphites without any problems at all.

For individuals who are sensitive to sulphites, it is advisable to seek out wines labelled as ‘low sulphite’ and be aware that Organic, Biodynamic and Natural wines tend to have lower sulphite levels. House of Townend’s long standing buying policy is focussed towards wine producers who farm organically and biodynamically, whether they choose to seek certification or not, so there are many to choose from. Additionally, being aware of and avoiding other sources of notable sulphites in the diet such as eggs, dried fruits, fruit cordials, processed food and prepared salads, which have much higher sulphite content than wines without any warnings on the label.

Not only are sulphites naturally occurring in wine… remember there is no such thing as sulphur free wine, they are actually pretty important for preserving their bright, fresh fruit flavours and for keeping wine stable enough to travel from its origins to the UK.

So, if you're concerned about sulphites in wines but have no reason to suspect you have a sulphite allergy, don't be — they won't hurt you. Sulphites are safe and are found all over the food industry. The fact of the matter is, you're far more likely to have a reaction to a handful of raisins than to a hearty glass of Barolo!



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