On The Grapevine: Sulphites in wine. friend or foe?

The use of sulphites in wine – or more precisely sulphur dioxide(SO₂) – goes back centuries. A chance discovery found that burning a piece of sulphur inside a barrel which was then rinsed with water, had a beneficial effect in sterilisation and hence longevity of wine subsequently stored in the barrel. Research later showed that sulphur dioxide has two main effects and thus uses for wine. The first effect is as an anti-oxidant, preventing spoilage of wine through excess exposure to oxygen in the air.

The second main use is due to the anti-bacterial effect of sulphur dioxide, particularly useful for controlling or eliminating acetobacter which turns wine into vinegar. The problems with sulphites occur when the level is too high, leading not only to an allergic effect, but to toxicity at high doses. Thus the maximum concentration of sulphites in wine is controlled by law. At carefully controlled levels, sulphur dioxide is thus more of a friend than a foe. It is also a natural product of fermentation at low levels and thus contained in virtually all wines.

Of course, as with all things, addition of sulphites is not straightforward. Sulphur dioxide in wine occurs in two forms – bound and free. When it combines and binds with other components in the wine, all the preservative effects are lost and it is only what is termed the ‘free’ SO₂ which remains active. Depending on the type of wine and length of time, more or less of the sulphur dioxide becomes bound. The winemaker thus has to calculate the dose which is added during winemaking and at bottling time.

As winemaking has improved massively over the past hundred years, helped greatly by technological advances, expert winemakers can determine the precise amount of sulphur dioxide to add, keeping this as low as possible whilst protecting the wine from spoilage. My own experience in talking to winemakers in different countries shows that there are substantial efforts being made to reduce the use of SO₂ to the absolute minimum, by keeping all winemaking processes as clean as possible and reducing the number of interventions made.

With the current trend towards healthy eating and drinking, a category of wines has developed termed ‘natural’ wines. As the term suggests, no additions or interventions of any sort are made. In my opinion and tasting experience, many of these wines keep for a very short period, lack charm and are unbalanced. There are, however, some wines on the market which are specifically made and labelled ‘no sulphites added’. When carefully made by an expert winemaker, these wines, although with a shorter shelf life than some other wines, are enjoyable, fresh and fruity.

Here are two definitely worth trying, particularly for those who have greater intolerance to sulphites. Les Enracinés Macon Chardonnay 2023 is a white Burgundy which is vinified and bottled without sulphites. Delicately fruity, fresh and floral pure expression of unoaked varietal Chardonnay, from vineyards near the village of Chardonnay itself. Around £15 -£18 from online merchants. Vin Sans Souffre a Butiner Beaujolais Villages 2022 is made from 50-year-old vines near Régnié by Chateau de la Terrière and has the typical strawberry and raspberry fruit character of Gamay, purple hue and crunchy fruit. Balanced, mellow tannins and medium-bodied with a delicious, fresh, clean fruit finish. Around £14-£16 from online merchants such as Eden Fine Wines.