Jim Wilson/The New York Times  The chef Michael Chiarello prepares a lamb chop at a recent gathering of Delta executives, chefs and catering representatives.  ONE of the world’s busiest airports, Hartsfield-Jackson in Atlanta, lies a mere 1,026 feet above sea level. Which, it turns out, is perfect for your taste buds.  At low elevations, the 10,000 or so taste buds in the human mouth work pretty much as nature intended. With an assist from the nose — the sense of smell plays a big role in taste — the familiar quartet of sweet, bitter, sour and salty registers as usual. Tomato juice tastes like tomato juice, turkey Florentine like turkey Florentine.  But step aboard a modern airliner, and the sense of taste loses its bearings. This isn’t simply because much airline food is unappetizing, although that doesn’t help. No, the bigger issue is science — science that airlines now want to turn to their advantage as they vie for lucrative business- and first-class travelers.  Even before a plane takes off, the atmosphere inside the cabin dries out the nose. As the plane ascends, the change in air pressure numbs about a third of the taste buds. And as the plane reaches a cruising altitude of 35,000 feet, cabin humidity levels are kept low by design, to reduce the risk of fuselage corrosion. Soon, the nose no longer knows. Taste buds are M.I.A. Cotton mouth sets in.  All of which helps explain why, for instance, a lot of tomato juice is consumed on airliners: it tastes far less acidic up in the air than it does down on the ground. It also helps explain why airlines tend to salt and spice food heavily and serve wines that are full-bodied fruit bombs. Without all that extra kick, the food would taste bland. Above the Atlantic, even a decent light Chablis would taste like lemon juice.  “Subtlety is not well served at altitude,” says Andrea Robinson, a sommelier who has selected wines for Delta Air Lines since 2008.  The science of airline food, which Delta, Lufthansa and other airlines have studied assiduously for years, has opened a new front in the battle for passengers in the upper-class cabins. Until recently, airline food seemed in terminal decline — another victim of widespread cost cuts in this long-troubled industry. Industry experts trace the problem back to 1987, when American Airlines removed a single olive from its salads to save a little money.  Anyone who has flown coach in recent years knows what happened next. Catering budgets were cut drastically. Free meals disappeared from cattle class. It might seem hard to believe, but flight attendants once whisked racks of lamb down the aisles on silver trays. Today, they hawk chips and soda.  But after years of belt-tightening, airline executives are investing again to attract business passengers willing to pay a premium for tickets, and food is a big part of that effort. This includes devising new menus and even hiring celebrity chefs like Gordon Ramsay, of “Hell’s Kitchen” fame, to consult. The motivation is obvious: business and first class account for about a third of all airline seats but generate a majority of the revenue. Keeping high-end customers is crucial to the bottom line.  THE industry can’t afford missteps. Airlines suffered mightily as travelers pulled back after the Sept. 11 terrorists attacks. In the decade that followed, domestic carriers lost a combined $60 billion as competition intensified and fuel prices rose. For many carriers, bankruptcy was the only option. American Airlines was the most recent major airline to do so, last November.  After so much turbulence, airlines are trying to chart a more profitable course through mergers and a renewed focus on business and first class. Many have installed flat-bed seats on some domestic flights, fancier entertainment systems and Wi-Fi.  But in the kitchen, science is still working against airlines. To crack the taste code, Lufthansa, the German airline, went as far as enlisting the Fraunhofer Institute for Building Physics, a research institute near Munich. Among other things, the airline wanted to know why passengers ordered as much tomato juice as beer — about 423,000 gallons of each annually. The answer was that for many passengers, tomato juice apparently has a different taste in different atmospheric conditions.  “We put a lot of effort in designing perfect meals for our clients, but when we tried them ourselves in the air, the meals would taste like airline food,” says Ingo Buelow, who is in charge of food and beverages at Lufthansa. “We were puzzled.”  So are many other people.  “Ice cream is about the only thing I can think of that tastes good on a plane,” says Marion Nestle, a professor of nutrition, food studies and public health at New York University. “Airlines have a problem with food on board. The packaging, freezing, drying and storage are hard on flavor at any altitude, let alone 30,000 feet.”  The journey from recipe book to industrial kitchen to a plane in midflight is fraught with peril. It’s not just a culinary feat — it’s also a logistical nightmare. The $13-billion-a-year airline catering industry serves millions of meals daily worldwide. It must maintain supply chains, standards and quality under a variety of local conditions.  “The cooking is the easy part,” says Corey Roberts, a chef based in New York with LSG Sky Chefs, the biggest catering company. “What we have to worry about is the logistics of getting the correct meal on the correct flight, on the right trays, into the right galley, at the right time. It’s a logistical puzzle of juggling all these meals, every day, for hundreds of flights.”
Carriers are turning to science and celebrity chefs to figure out how to make onboard meals more appealing to high-revenue business travelers.