It is estimated that as many as 8% of wine drinkers suffer from Wine allergies. The Globe and Mail reported in their January 11th issue, recent news out of Denmark that could help many.
Researchers in Denmark have isolated substances in wine, called glycoproteins, proteins coated with sugar, that they think could be the root of many wine allergies. Most allergies, are due to proteins, and not sulphites or tannins which are not proteins. Wine makers maybe able to adjust their procedures to eliminate these glycoproteins, but this may be a long way off.
These glycoproteins are naturally occurring compounds in the grape plants that give the plant protection against pathogens. Plant breeders may choose to look at eliminating these glycoproteins and solve the headache. Stay tuned!
Sulphites in wine have for a long time been falsely thought to be the culprit. However, it is really only severe asthmatics that have to be wary of this substance, and that is why many commercial wines contain the warning that the wine contains sulphites. Sulphites are also naturally occurring, so, in fact all wine contains sulphites, even humans produce sulphites. Salad bars, dried fruit, and meat products (that pad on top of that Styrofoam tray in your steak from the supermarket is rife with sulphites to keep your steak red) contain far more sulphites than a glass of Merlot.
Tannins, on the other hand, can restrict blood vessels and result in headaches. These antioxidants give wine that popular astringent taste. It is more common in red wine, as red wine is fermented on the skins. Of course you will also find that astringent taste in tea and walnuts which have far more tannins than the average glass of red wine.