By Natalia de la Calle

Wine is composed of juice from fermented fresh grapes. The must is fermented using yeasts, which turn the sugar into alcohol and carbon dioxide. Therefore, the transformation of the must in wine is a chemical reaction, which can occur spontaneously or provoked by man.

Furthermore, to avoid unwanted oxidative processes, we can turn to the help of additives, such as sulphites. Well, for some months now I have spoken with wine enthusiasts who are concerned about this: the blessed sulphites. In this article, I hope to clear up my readers' main concerns by shedding a little light on this mysterious substance.

Community Directive 2003/89/EC on ingredients and the labelling of allergens lays down the requirement for information on the label about certain substances or ingredients that can produce allergic reactions. Among many common foodstuffs, such as almonds and milk, the Directive includes sulphur dioxide and sulphites in concentrations of more than 10 mg/litre expressed as SO2. The Directive also explains that foodstuffs that do not require a list of ingredients (as is the case of wine) must indicate the inclusion of an ingredient that can produce an allergic reaction using the expression contains...

The terms of the Directive have been incorporated into Spanish legislation by Royal Decree 2220/2004, of 26 December 2004, whose application included an extension until 25 November 2006. The royal decree requires wine-growers to include the legend contains sulphites on their labels if their content in the wine is higher than the proportion indicated by the standard.

Now we know why and since when labels have had to carry this legend, but I think it is more important to answer the most frequent question consumers might ask: why does a substance as natural as wine contain something as unappetising as sulphites? Is it because today's wines contain sulphites? Are they a health risk? The answer is simple. The technique of using a powerful preservative such as sulphur in wine is as old as it is necessary. Sulphur is added to wine as an oxidant to remove unwanted yeasts and control fermentation. Wine could be made without sulphur, but it would be left to the erratic and random behaviour of certain yeasts and, consequently, its quality could not be guaranteed. Therefore, 100% of the wines analysed by the OCU (the Spanish Organisation of Consumers and Users) in a study carried out in 2005 contained sulphites, as did 80% of shellfish and meat products. This means that wine-growers have to add SO2 to their wines to ensure its preservation. This generalised use of sulphur in many foodstuffs is due to the fact that, as a preservative, it is appropriate for human consumption. At this point, it is appropriate to make two things clear:

1. The fact that as from a few months ago it is necessary to indicate that a wine contains sulphites does not mean that they weren’t present in wine before. What's more, sulphites are present in the same wine to which the WHO continues to attribute a long list of benefits.

2. The warning is for people who are allergic to the sulphites contained in the wine. This means that people who are not allergic should not worry in the least about the warning, since, for them, it is not a health risk.

The truth is that the contains sulphites indication has caused more problems than benefits, since it confuses consumers by warning them of the presence of a substance contained in all the wines on the market. According to medical studies, only 2% of the adult population suffers from allergic reactions to foodstuffs and the proportion is much lower in the case of those who are allergic to sulphites.