I am often asked why almost all wines contain sulfites and if it is really necessary. The reason why most wines have a small amount of sulfur is to protect them from deterioration, predominantly from bacterial attack but also from oxidation. It is used both as a preservative and as an antioxidant so that the wine can be preserved for a reasonable time without deteriorating. Sulfites are also introduced to stop fermentations at the desired time.
Yeasts are naturally found in grapes and therefore also in wine. It is these yeasts that consume the sugar from the grapes during fermentation, producing by-products of carbon dioxide and alcohol. When fermentation is complete, most of the yeast cells will die and be removed from the container by racking (pumping liquid from a sediment), but some will remain inside. Without the addition of a controlled amount of sulfite, the wine could soon develop off-flavors and become ‘musty’ very quickly.
Winemakers know how much sulfite to add after analyzing their wines, and if the addition is excessive, it will be very noticeable on the nose and the overall flavor in the glass. The secret is to make your wine in the most hygienic environment possible, preferably in a stainless steel container, and check the wine for yeast or bacterial growth regularly, and then act immediately.
Sulfur is a common element found naturally in food, nature, and the human body. The term ‘sulfites’ covers the use of sulfur-based preservatives, sodium and potassium metabisulfite, as well as sulfur dioxide gas (SO2). In home winemaking, Campden tablets are the common sterilizing agent and antioxidant (these tablets contain approximately 60% SO2).
So what is the connection between headaches and sulfites in wine?
Headaches have been said to be caused by the sulfites in wine, but there is no direct proof of this. In fact, most headaches are caused by excess alcohol, leading to dehydration. If you were one of the small percentage of people who have a sulfite allergy, you would suffer serious breathing difficulties, rather than headaches, from consuming any product that contains them. There are several studies linking sulfites to the cause of respiratory and asthmatic problems.
Some facts about sulfites in wine:
- Almost all wines contain sulfites, which means that most winemakers in major wine-producing countries add sulfites to their wines.
- Very few organically produced wines will be completely free of sulfites. This is a requirement for an organic wine. The main drawback is that the wine will not keep for long, so it will have to be consumed almost immediately.
- Sulfites in wine do not cause headaches, there is something else in red wine that does, but has yet to be fully discovered. The bitter-tasting tannin in red wine is sometimes blamed for causing headaches.
- There is a law in most countries that governs the maximum amounts of sulphites allowed in wine. In some of these countries, this information must appear on the label.
- A team of scientists from Spain has found that by using ozone instead of sulphites, this has resulted in high levels of antioxidants being retained in the wine and therefore quality is guaranteed.
Therefore, to avoid headaches and the dreaded migraines, the simple answer when drinking wine is to consume less and at the same time drink large amounts of water (glass for glass if you can). Drinking wine with food and appreciating both is my advice!