When a voice on the loudspeaker announces that it’s now O.K. to unfasten seat belts and switch on electronic devices, aircraft passengers begin to relax. There are two reasons for this release of tension. Everyone has survived the take-off unscathed and the drinks trolley is not far away.
Anxiously scanning the wines on offer, you spot a familiar label. But when it arrives, the wine does not taste familiar. What’s going on? Has the winery used a cut-price blend for a special airline bottling?
I spoke recently to a wine buyer for an international carrier who explained that the answer is simple: wine tastes different at 30,000 feet. White wines tend to lose a little flavor and red wines become more astringent. Airline wine-buyers try to compensate for these changes during the screening process, selecting flavorsome whites and softer reds. Look at any airline wine list and you’ll see that subtle is out and soft is in.
When Air New Zealand invited me to taste identical wines with my feet on, and off, the ground, I discovered that the differences were obvious, if not profound.
The airline had a ready explanation for the extra astringency in red wine. A pressurized cabin has a very dry atmosphere. When we taste a tannic red we automatically salivate.
It’s such a strong response that when I pour myself a gutsy red and raise the glass to my lips I can feel myself salivating in anticipation of the tannic hit. Protein in our saliva wraps around the tannin molecules in red wine, making it appear softer. In a dry atmosphere we become less efficient at salivating, so red wines taste more astringent.
Searching for an explanation for the loss of taste, I came across a 2010 study by German researchers from Leitthema Neuromarketing. Using a test facility in Holzkirchen, they simulated conditions on board an Airbus A310-200 at all stages of a flight, to study odor and taste perceptions at low and normal air pressure.
In the researchers’ view, influences on board an aircraft include reduced atmospheric pressure, low humidity, noise, cosmic radiation and magnetic-field exposure. While acknowledging that reduced humidity could play a part in flavor loss, the study found that reduced oxygen absorption (or hypoxia) might also be responsible.
Observations by cabin crew suggested passengers preferred highly spiced foods and extra salt with their meals to compensate for this diminution of flavor. They also noted that increased consumption of tomato juice is a common phenomenon on board airliners.
Meanwhile, sommeliers tasting their wines at higher altitudes reported a loss of flavor and an obtrusive alcohol smell. The researchers used three white wines and two reds, all chosen from the Lufthansa wine list.
The whites were the 2008 Ihringer Winklerberg Weissburgunder (pinot blanc), 2008 Andreas Bender Chardonnay Eiswein, and 2007 Reichsgraf von Kesselberg Riesling, while the reds were the 2002 Château Belgrave from the Haut Medoc, and the 2003 Sartori Amarone Della Valpolicella from Italy.
The study revealed that both the white and red wines lost flavor in a pressurized aircraft. The white riesling became more acidic, while the pinot blanc developed an “obtrusive alcohol smell.” (My own theory is that any loss of flavor would likely expose acid and alcohol that it had previously masked.) The wines that showed best at higher altitudes were the more intensely flavored Italian Amarone and the chardonnay ice wine.
The researchers said their general recommendations were that light and fresh wines lose their flavor in the air while being perceived as intensively alcohol-like, while very intense, deep, aromatic wines remain stable.
Regardless of the taste, boredom – and the fact that on-board wines are often free – can lead passengers to drink too much. Do airlines therefore specifically seek out lower-alcohol wines as a preventative measure?
John Belsham, wine consultant for Air New Zealand, says not. However, like the researchers, he knows that the change in cabin pressure at cruising altitude means alcohol tends to become more obvious. “For that reason wines with slightly lower alcohol may be favored.”
In broad terms, says Belsham, wine selection for high-altitude quaffing mirrors market demand. Therefore, “popular wines like chardonnay and sauvignon blanc feature strongly, while less-popular wines such as gewürztraminer or riesling have a lower profile."
As for the wines being free, Belsham reports that business and first-class passengers in particular “are inclined to be slightly more adventurous than they might be if they were paying for a bottle of wine.” For example, Trinity Hill Viognier was added to the Air New Zealand wine list some years before the grape variety became a rising star. It proved to be very popular.
My conclusion? When up in the air, steer towards more intense, deep and berry-like wines, and avoid those that are light, fresh and acid rich.