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Cochrane's Tasting Pleasures: In Defence of the Wrongly Accused— Sulfites

Your favourite wine gives you headaches. You reason it must be the sulphites (S02). After all, it sounds "chemical," and it's spelled out on the label.
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Your favourite wine gives you headaches. You reason it must be the sulphites (S02). After all, it sounds "chemical," and it's spelled out on the label. The truth is that wine is complicated, and sulphites play only a minor role in wine making. Something else may cause your impediment.

Let me explain. 

Wines, like any other food, are available in a range of quality— From mass-produced "conventional wines" to wines vinified using nothing other than what nature offers, such as in "natural wines." Between those two extremes is a range of vine growing and vinification techniques using fertilizers, pesticides and additives to varying degrees. The bread offers a good analogy to wines. The mass-produced light white bread void of nutritional value that seemingly stands the test of time on the shelf akin to the mass-produced conventional wine, whereas the heavy organic artisan sourdough bread with a best before date akin to the organic wine. 

However, before we go further down this rabbit hole, what are sulphites? 

Sulphites or Sulphur Dioxide (SO2) is a compound naturally found on fruits or vegetables (i.e. grapes, broccoli, onions, plums, strawberries and more). It has antioxidant and antimicrobial properties that are slowing down the rate of browning and rot. For this reason, no wine (or broccoli) is entirely sulphite-free. 

SO2 has been used for centuries and is widely used today in processed food. While wine may have anywhere from 20 to 300 ppm of SO2, dried fruits such as apricots have up to 3,700 ppm, and French fries about 1,850 ppm. Canned food also contains generous amounts of SO2. Therefore, if your poutine doesn't give you headaches, chances are the SO2 in the wine will not. Still, according to the American Federal Drug Administration, it is estimated that about one per cent of the population is sensitive to SO2, especially those suffering from asthma. For this reason, the United States and Canada, require the “contain sulphite” on their labels. 

Meanwhile, there are several other compounds in wine that should give us pause. Alcohol, naturally occurring histamines, tyramines and flavonoids may trigger allergic reactions. Furthermore, over 70 additives are allowed in "conventional wines," including the likes of— Copper Sulfate, Tartaric Acid, Acetaldehyde (colour stabilizer), Casein, potassium salt of casein (to clarify the wine), Protease (Trypsin) and Protease (Pepsin derived from porcine or bovine pancreas) to reduce or to remove heat-labile proteins. Most of these compounds and additives are harmless in small quantities but not necessarily in large ones.

If you do not have time to witch hunt the harmful chemicals or compounds that affect you, I suggest you turn the problem on its head and start exploring wines that are the least likely to contain harsh chemicals and see how your body reacts. First, establish which category of wines is giving you headaches (is it a conventional wine?). Second, taste wines from the classes that are more natural (say, organic wines). Then, do this with white and red wines. Warning, this may be challenging and pleasurable.

Here’s a low down on the wine classes. 

Natural wines do not allow any use of human-made chemicals in the field or the vinification process. The juice is fermented on its own accord using wild yeast present in the air. To a large extent, these wines are an acquired taste as they may be more acidic and lean on the palate.

Vegan wines are usually organic or biodynamic wines that have excluded the use of animal-based by-products. For example, in the filtration and clarification process using egg whites and collagen extracted from fish bladders.

Biodynamic wines— The vine growing and winemaking are the same as organic but with an added layer of concerns for the dynamic interplay of the Earth's elements - earth, fire, air and water, and cosmic energies that impact fruit quality and wine. Winemakers practicing biodynamic culture will go to a great extent to avoid having to use additives. 

Organic wines are becoming increasingly mainstream. One of the primary reasons for this is that making organic wines is one of the best approaches to express the local terroir and the uniqueness of a wine region. An organic wine simply means the absence of or the use of chemicals below a legal threshold acceptable by a third-party certification body. Worth noting, many winemakers use organic practices but will not label their wines as such. Either because they are not quite there yet or the certification process is too costly. Furthermore, the "organic" label still carries a somewhat negative stigma that may impact the marketability of a wine. 

Sustainable wines may or may not be organic. The aim is to cultivate the land, make and sell wines in ways that support the natural environment and the community where the winery is located. Examples include low-impact farming practices and providing good working conditions and salaries to seasonal employees. 

Conventional wines are still the most popular wine class but are gradually losing ground in favour of the practices mentioned above. Wines in this category can be found along a continuum. On one end, you will find many small producers that pride themselves in offering wines of quality with minimal intervention. They often make excellent wines, though, they do not quite meet the threshold that defines the other wine categories. They are often "family own" wineries, and we have many of them in Canada.  

On the other end of the spectrum are wines made from grapes grown in vineyards cultivated to maximize yields and vinification methods designed to produce consistent wines year over year regardless of circumstances. Those wines are highly manipulated and tend to be made on industrial scales. 

Wines have complex makeups and come in many shades of quality. Daunting as it may be, finding the ones that work for you can be a pleasurable pursuit. Knowledgeable staff in a quality wine store are there to guide you. Visiting wineries, asking questions and making notes may also go a long way to reducing the pang in your head. That and, drinking water before sipping wine...

And on this, members of the jury, I rest my case.

Renée Delorme is a sommelier specializing in private wine tastings.
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