We’ve had a few enquiries about the wording on wine labels that reads “contains sulphites” which does tend to look scary as if somehow wine has suddenly had some sinister additive included suddenly. In fact, it’s just one of many tools used by winemakers, and it’s a labelling rule that tells only half the story.
Currently only a few things have to be declared on the label on a bottle of wine sold in the UK
Regulations stipulate that information such as the size of the bottle, the alcoholic content, the bottler’s details, country of origin and type of wine must be there, as must the stipulation of the presence of Sulphur Dioxide if it exceeds 10mg per litre (10 parts per million).
A quick chemistry lesson then, if you will indulge me for a moment… The word “Sulphites” most likely refers to Sodium Metabisulphite or Potassium Metabisulphite which are the most common means of getting a bit of Sulphur Dioxide gas into wine. Sulphur Dioxide (SO2) is an important part of winemaking, but will be controlled by the winemaker as one part of the complex process of winemaking. Some SO2 will almost certainly remain in the finished wine which would otherwise be unstable. The trick is to use as little as possible of course.
So, bottles of wine making no declaration on the presence of Sulphites contain less than 10mg/litre but you would be wrong to assume that they contain none at all. Equally, those carrying the Sulphite wording will contain at least that level, but it is currently impossible to determine whether it’s 11mg/litre or 40, or more. Sulphites and Sulfites are the same thing of course, but I make no apology for using the correct spelling here despite the fact that the next generation are having the ugly transatlantic “Sulfites” and “Sulfur” forced upon them at school.
So why are Sulphites necessary?
What does SO2
Well, it really does two jobs; firstly, it knocks out stuff like bacteria that would otherwise mess up the winemaking - it also ensures that any remaining yeast cells don’t suddenly wake up once the fermentation has finished and begin an unwanted secondary fermentation.
A secondary fermentation may be desirable though – as in Champagne
acts as an anti-oxidant, essentially keeping oxygen at bay and keeping the wine fresh – unless oxidation is a desired part of the winemaking process of course – as in some Sherries.
Some wine producers tend to create a vacuum in their bottles before bottling which removed 90% of the Oxygen which would otherwise be present. This means that they need to use less SO2 to shut out the oxygen. Some producers do it twice – so that’s 90% of the oxygen excluded, followed by 90% of the 10% that remained after the first go. This costs money of course, and is unlikely to have been done to wines on the 3 for £10 shelf!
Buying Organic wine isn’t much help either I’m afraid. This is because the statement on the label of “wine made from organically grown grapes” is fine, as far as it goes, but that only covers the grape growing, not the winemaking, and most wines made from organically grown grapes still say “contains sulphites” on the back label. The issue, of course, is how much! There’s no doubt that more accurate labelling would help consumers make a more informed choice, but until that time arrives buying from a respected merchant, who in turn buys from smaller, caring producers would be a good start if you need to keep the Sulphite levels down.
It would not be unreasonable to suggest that the wines sold (and therefore made) on a massive scale, with price as the main consideration, are more likely to be subjected to a commercial mass production process where Sulphite levels are less likely to try and be lowered, there’s no incentive to do this of course whilst the current labelling requirements remain, and what the supermarkets want is a product that will remain stable however long it’s on their shelves – they don’t care whether you’re allergic to some of the contents.
I’m allergic to cats. And horses. My eyes itch and puff up and my asthma kicks in as well just to make sure I’ve got the message. I have never known why, or to which precise bits of them I have an allergy, so I tend to keep out of their way whenever possible. I have worked out that Siamese cats are usually OK though. Mostly. But not consistently enough to give me any confidence. I found this out by trial and error over time, and with the help of many Piriton tablets. Not sure whether this works with SO2 allergy though.
It seems the only way that those with an allergy to SO2
can discover which wines they can drink until levels are clearly expressed and we can really see who the bad guys are.
Maybe one day cats and horses will come with allergy labels too?
Further discussions with Italian winemaker Claudio Lenotti have revealed that the legal maximum for sulphites in wine are 200 mg/litre for white wine and 150 mg/litre for red wine. Claudio goes to great lengths to exclude unwanted oxygen at every stage of the winemaking process, from fermentation to bottling. These mainly involves rigorous hygene, tight monitoring methods and the use of Nitrogen throught the process. The bottom line here is that processes exist to enable winemakers to manage with lower sulphite levels, but they all cost money so this is as much a commercial decision and a heath or aesthetic one. For more details on this visit the following page of Lenotti's website. http://www.lenotti.it/en/dettaglio_tecnologia.asp
It's worth re-stating though that wines made to a price point are more likely to have higher sufphite levels simply because it's the easiest, and cheapest, way to deal with the problem of unwanted oxygen. If you have an allergy to sulphites we'd be interested to know how you get on with a bottle of Lenotti's Colli dei Tigli (white) or Rosso Passo (red) since these are winemakers who know, understand, and have taken steps to address the problem of sulphite levels,and do all they can to keep them to a minimum.