by Erin Winsper, Assistant to the winemaker at EdenVale Winery
As a chemist in the wine industry, tasters often ask me about the cause of wine related allergies, particularly from reds. Since my son has food allergies, I had always had a personal interest in the cause of allergies. However, it wasn’t until this past December that I developed an analytical interest when I experienced allergy symptoms while working with wine.
Sulfites in wine typically take the blame for allergy symptoms like flushing, headaches and rashes during wine consumption. Sulfites are widely used in winemaking as a preservative because of their antioxidant and antibacterial properties. This past winter, I fell ill to these same symptoms while collecting barrel samples of wine for a secondary fermentation analysis. I had never experienced these symptoms before, and knowing there were very little sulfites in this particular wine I had to discount the sulfites as the cause of my troubles.
After a little research into other causes of wine related allergies, the real culprit to my red flush and headache appeared to be histamines. Several sources for histamines in wine range from vineyard fertilization, to grape rot and mold, even grape skins have histamines. This is one reason reds are more intolerable than whites since white wine spend no time on their skins during primary fermentation, where red’s primary fermentation is completed entirely on their skins.
The yeast used in the primary fermentation process is another source for histamines, but at a relatively low level in comparison to the bacteria responsible for the secondary fermentation. This is another reason whites are more tolerable than reds, as they rarely go through secondary fermentation step.
Winemakers can reduce histamines by sorting fruit, using microbe strains that produce no histamines, or even using bentonite, an agent which removes them. This is already a common practice in dry whites, another reason why wine drinkers experience fewer reactions to white wine.
In comparison to many other foods, wine histamine levels are low, but the alcohol increases absorption of histamines, while acetaldehyde in wine inhibits the enzymes that metabolize them, and there are other amines that will compete for these enzymes. For consumers taking an anti-histamine before tasting should help, but for me, I must force myself to spit the wine I sample while syphoning barrels with elevated bacterial leveIs; although it’s quite the battle in my mouth to keep from swallowing when I am surrounded by so many delicious wines.