Who doesn’t know someone who swears they can drink wines when they are in Europe but has a reaction to wine back home? Theories abound as to why this occurs, but none of them completely explains the problem. Suspect sulfites? Maybe, but that is almost certainly not the issue for most. Pesticides possibly? A tasting room server pressed that idea on me recently, claiming that American winemakers use more of them and they accumulate in our fat tissue over our lifetime, increasing our sensitivity to them. But evidence suggests otherwise, at least as far as pesticide use is concerned. Is it lower alcohol content? There is a persuasive case to be made for that, but as European winemakers chase higher scores, the alcohol content increases there too. Each of these premises may apply to some degree, but I have another idea to toss into the mix: I think that when we are in Europe, we drink differently. We are probably on vacation, and we are more relaxed. We are more likely to drink in a traditional way, with meals and at a more leisurely pace.
Sulfites are often blamed, though they are not clinically documented as a cause of headaches, and true allergies are uncommon. Because sulfite (SO2) is necessary to prevent spoilage, all wines have some, but many common foods have much higher amounts. One hypothesis is that it is a combination of alcohol content, pH, and SO2. The lower the pH (meaning the higher the acidity), the less SO2 you need to add. Just going from a pH of 3 to 4 translates to a 10-fold increase in added sulfite. In general, Old World wines have lower alcohol and higher acidity. A typical European white (for example, the Grüner Veltliners that I had in Austria a few weeks ago) might check in at 12.5% alcohol and a crisp pH of 3.2, requiring only tiny amounts of added SO2, while a California red might register more than 15% and a less bracing pH of 4.1, toting a sulfite level an order of magnitude higher. According to this line of thinking, the higher alcohol combined with the much higher sulfite levels is a recipe for trouble. If you want wines with low SO2 one guideline is to look for wines with higher acidity, typically from microclimates with greater diurnal temperature variation (such as we have here in Washington State.)
Ashley Trout (Vital Wines, Brook & Bull) also implicates sulfites, but she reminded me that they dissipate with aging. Because European wines are more often allowed to mature before they are consumed, she says, the free sulfites have had time to diminish. In any case, the sulfite question is a bit of a moving target; it’s a natural organic molecule, sweet whites need more regardless of acidity, tannic reds need less, and levels change with time.
Don’t blame the pesticides
Data on comparative pesticide levels in Old vs. New World wine reveals that if anything most European wines have more. A couple of years ago a French consumer organization called UFC-Que Choisir tested 92 wines from around France, and found traces of pesticide in all of them. Bordeaux and Champagne were the worst offenders, because their high humidity promotes mildew, necessitating more liberal use of antifungals. Drier locations such as Provence fared better. Experts insist however that levels are well below toxic amounts. In any case, it is a worldwide issue and not delineated by Old vs. New World viticulture practices.
Bob Betz, MW, takes a somewhat different tack. In his view, the whole issue is “one of those vinous myths” noting that “If you look at the macro chemistry of US and European wines they are clustered around the same set of numbers.” Sure, higher alcohol has been a trend in New World wines, but not exclusively. Basically he thinks that maybe the quality of domestic wines has improved so much that we just like them more and drink more. We are more likely to overindulge because the wines are so delicious!
It’s how you drink more than what you drink
I think this idea of how we drink, more than what’s in the drink is closer to the truth. We do drink differently when traveling; consciously or unconsciously, at home we might drink to de-stress, but take a more relaxed approach when away. We discovered some nice “lunch wines” in Europe on our last trip (ever tried a dry Tokaji?), but even with the lower alcohol content, that is not something that would be acceptable during the workweek here. Evenings it tended to be a bottle with dinner. Wine as a food, with food, also slows the absorption of alcohol, and the polyphenols neutralize the effects of fats and oxidants in the meal. Like the larger issue of wine and health, the answers are probably to be found in common sense more than in chemistry.