If you’ve ever brought a favorite treat along to enjoy on a flight – a special chocolate bar, stacked-high sandwich, or flaky pastry, say – you might have noticed it didn’t taste as great at 30,000 feet. It’s not just you. Flying has a very real effect on the smell and taste of food and drinks for a number of reasons. Herbert Stone, who has a PhD in nutrition, worked on food for the Apollo Moon Mission. He says that says chilly airplane temps are partly to blame. We don’t taste flavors as well when it’s cold. Remember too, that taste and smell are inextricably combined, so what affects your sense of smell impacts tastes big-time. Pressurized cabins lower blood oxygen levels, and that reduces the ability of olfactory receptors. And the constantly circulating, super-dry air of the airplane cabin—an average 12 percent humidity, lower than that of the Sahara Desert—directly affects the nose. “Low moisture and air movement will dry the nasal passages and this reduces odor and taste sensitivity,” says Stone, who adds that when the exact same food is tested at sea level, “it will be rated as stronger and more intense.” Then there’s the noise—the drone of the airplane’s engines, the baby screeching in the back row—also affects how food tastes. Additional research has shown that no matter the environment, flavor perception is dampened by loud background sounds. Some tastes are affected by these factors more than others. “Salt is perceived to be between 20 and 30 percent less intense and sugar 15 to 20 percent less intense, at high altitude, according to research by the Fraunhofer Institute for Building Physics that was conducted for Lufthansa. The perception of fruity aromas and acids is by contrast more stable,” according to research by the Fraunhofer team. And this might be a conservative estimate: “In the air you lose almost 70 percent of your sense of taste,” says Antonio Fernandez, AeroMexico’s senior vice president for on-board product. Considering all of these factors, it’s not a big surprise that the salted caramel macaron that explodes your taste buds with flavor on the ground tastes like a ghost of itself in the air. But savvy airline chefs know that some flavors do better than others in the sky: Spicy and intense flavors remain pretty stable at altitude—like a Thai or Korean curry, and so does fresh fruit, especially citrus. Umami flavors–like those found in mushrooms, seaweed, hard cheeses and meat–lend richness and depth to dishes, and they come through well, too. “Flavors such as cardamom, cinnamon, ginger, parmesan, tomato, mushrooms, soy, meat and lentils” are the go-to flavor-enhancers for Aeromexico’s chefs, says Fernandez. Cuisine that relies on subtle flavors (like how fish, pasta or poultry might normally be prepared) end up the big flavor losers and lead to complaints, food scientists have found. “Typical reactions include words like ‘tasteless’ and ‘cardboard’,” says Stone. On top of all the taste-perception challenges, food prep areas aren’t exactly restaurant-quality at 30,000 feet. Flight attendants aren’t sous chefs, and space is at a premium. There’s only one oven and an entire entree must be cooked at the same temperature for the same amount of time. “I actually liked the challenge that this proposed because it allowed me to get creative on how to keep some things crunchy, some soft, and all hot and delicious,” says Brad Farmerie, the Executive Chef at New York City’s Saxon + Parole. He developed the menu for Mint, JetBlue’s premium class of service. He said getting a soft-boiled egg for brunch items or being able to offer a medium-rare burger was a challenge that took some time to successfully crack. Some airline chefs will just ramp up sugar and salt to make up for lost flavors and less-than-ideal cooking circumstances. “This just adds to the dehydration that travelers feel during and after the flight,” Farmerie says. When he developed a menu for the airline, “I knew that I needed to incorporate acidity, heat and umami to make up for the muted sense of smell and taste. These elements give the cuisine a ‘lift’ and brighten the natural flavors of the dish without the need for more salt,” he adds. Farmerie cites the airline’s popular carrot and ginger soup with chili marshmallow as one that ticks all the boxes: It combines fresh carrot flavor with white miso for umami, lemon juice for acidity, and ginger and chili for sweet spice, all of which provide flavor without extra salt or sweetener. Whether you order on board, buy food at the airport, or bring your meal from home, keep in mind that simple, healthy foods are what most chefs who are frequent fliers choose: Fruit and cheese plates (err on the side of harder cheese when it comes to security restrictions); Asian stir-fries; and vegetable soups like carrot or tomato. And maybe throw one of those travel-size bottles of hot sauce into your carry-on bag.