Scientist Discovers Big Clue in Wine Reactions

in Other Food Allergy
Published: December 19, 2012

Reprinted from Allergic Living magazine, 2011

The baseball game hadn’t even started when Kishari Sing began to feel that something was seriously wrong. She knew that, like her father, she reacted badly to alcohol; even a small taste of Irish Cream in high school had made her wheeze. Still, in the parking lot outside the San Diego stadium, her college friends tried to convince Sing that she could build up a tolerance to alcohol, and specifically to their drink of choice – a cheap boxed rosé. She drank one glass and remembers little after that.

“It completely whacked me out. I was sick the entire time,” recounts Sing, now a marketing executive in Los Angeles with a blog called The Food Allergy Queen.

“There’s a picture of me at the game, and there’s this row of fraternity guys cheering – but I’m all red and puffy and trying to sleep on someone’s shoulder. I was completely incapacitated.”

Fortunately, the reaction to the cheap vino didn’t progress any further – but it was serious enough to keep Sing away from wine for good. “It made me so ill,” she says. “So it really wasn’t worth it.”

Sing is not alone. In fact, roughly 8 percent of people worldwide suffer from allergic-type responses to wine, and even relatively small amounts of the age-old drink can lead to symptoms including redness, itching, swelling, runny nose, headaches and asthma flare-ups.

Some people have true allergic reactions to wine ingredients – in rare cases to the point of anaphylactic shock.

But a new study out of Denmark may be the first step in turning those avoiders into connoisseurs who can sip hardy cabernets and oaky chardonnays with impunity. Until now, sulfites – which are used as a preservative in many wines and also can occur naturally – have borne the brunt of the blame for the allergy-related reactions.

Yet only a fraction of people who are sensitive to wine are sensitive to the common preservative. Yeast, tannins and grapes in the vintages are also known to set off allergy symptoms, while histamines and salicylates are linked to intolerance.

The Danish study, published in the Journal of Proteome Research, reveals a completely different potential allergy culprit: glycoproteins. Titled “Glycoproteomic Profile in Wine: A ‚ÄòSweet’ Molecular Renaissance”, the study looks at the molecular makeup of wine – a 2008 Italian Chardonnay to be exact – and identifies 28 glycoproteins (proteins that are coated with sugar during the fermentation process).

Ironically, the study’s lead author Giuseppe Palmisano, who grew up helping his Italian winemaker father pick and press grapes, had not intended to study the potentially allergenic components of wine.

But in the process of analyzing the glycoproteins, and looking at what similarities they shared with other foods, he made the stunning discovery that they have a very similar structure to the proteins in known allergens, including latex, ragweed, bananas, tomatoes and kiwi. Palmisano, who is a post-doc in chemistry at the University of Southern Denmark, was so surprised that he checked and re-checked his data many times.

Once he was certain the data were solid, he was both thrilled and somewhat afraid, since the tiny Italian town where he grew up, along with many others like it, are highly dependent on the wine industry.

Next: Can wine be made hypoallergenic?