People have got all sensitive about the chemicals. Are they a problem ingredient or simply an opportunity to push more free-from products?
Talk to me about sulphites
It was the Romans who inadvertently discovered that sulphites helped make foods last longer. They occur naturally in many things, including the human body, but because they have antioxidant and antimicrobial properties they are widely used in the food and drinks industry as an additive to preserve quality, colour and flavour.
Sulphites consist of a group of sulphur-based chemicals, including sulphur dioxide (SO2). Its commercial forms include potassium bisulphite or potassium metabisulphite; sodium bisulphite, sodium metabisulphite or sodium sulphite; and sulphur dioxide, (which is technically not a sulphite but a closely related chemical oxide). Sulphite food preservatives such as E220 and E228 are used in the UK.
What foods and drinks commonly contain higher levels of sulphites?
These include wine, cider, soft drinks, frozen seafood, sausages, dried fruits, fruit yoghurts, bottled lemon juice, fruit juice, jam and breads as well as foods containing vinegar, such as mayonnaise, pickles and sauces. Processed potatoes, potato starches and anything containing stock cubes, dried onions, dried mushrooms or dried garlic are also culprits.
Sulphites and sensitivity
Our bodies contain sulphites naturally. However some people do experience allergy-like symptoms on exposure to them, particularly asthmatics. That is rare, though – estimates put sulphite sensitivity at less than 2% of the general population.
An oft-repeated myth is that sulphites in wine cause headaches but that isn’t the case. They can cause allergy and asthma-like symptoms for those who are sensitive but the idea that it’s the sulphites in wine that are causing your headache is hogwash (unless you believe the Daily Mail).
So why the fuss?
The headache myth, a focus on allergies and the interest in what goes into processed food and drinks have all made sulphites a target for scrutiny. They occur naturally in wines but for centuries winemakers have been adding them to halt the fermentation process and prevent the grape juice from turning into vinegar.
These days more and more wine is shipped in bulk and bottled far from the vineyards, in order to reduce costs and the environmental impact. The suggestion is that very large quantities of sulphites are needed to keep such large volumes of wine stable, but there’s no evidence to suggest there are more sulphites in wine – or anything else – today.
Are they unsafe in large quantities?
There is very little evidence to suggest sulphites are harmful to health – except to those who are allergic to them. These people can suffer respiratory problems on exposure and this can be very serious.
There have been fatal cases in the US and a spate in the 1980s prompted the US government to act. It now bans the addition of sulphites to all fresh fruit and vegetables that are eaten raw and to declare that all food and drink containing sulphites in quantities more than 10 parts per million have to state “contains sulphites” on the label.
Does the UK require labelling on sulphites?
Yes. EU regulations passed in 2005 require all food and drink sold to clearly show on the label if it contains sulphites at levels of more than 10mg per kilogram or 10mg per litre. They are also counted in the UK as one of the 12 potential allergens (alongside the likes of peanuts, milk, crustaceans and gluten) in the Food Information for Consumers Regulations.
Another free-from opportunity?
Currently there appears to be no official concern about sulphite levels in our food and drink but the debate has intensified in some consumer circles. Some brands have spied an opportunity in sulphite-free products.
A few winemakers are already capitalising on this, such as the French producer Les Domaines Paul Mas, which now produces and promotes about half of its white wines and a quarter of its red wines as sulphur-free.
These products will appeal to much more than the 2% of the population who suffer from allergies: 27% of Brits say they or someone else in their household avoid certain ingredients as part of a general healthy lifestyle, compared with 19% who report avoidance due to an allergy or intolerance.
What’s the bottom line?
Sulphites are safe for most people and there is no evidence to suggest there are increasing amounts in our food and drink or that – even if there were – this would pose a health risk for the majority of people. If products are labelled correctly, according to the guidelines, sulphites should cause no problems.