So what's the deal with airline food, anyway? I mean, it's bad, it's bland, and a lot of the time they still make you pay extra for it. But it's not necessarily the airline's fault that the food doesn't taste good. Turns out it's actually your fault.

Well, to be more specific, it's your taste buds' fault. See, how your taste buds perceive the flavor of food is influenced by a few major factors including humidity, air pressure, your sense of smell, and, weirdly enough, your hearing. And when you're flying in an airplane, all of these factors change by quite a bit.

Comfortable humidity levels for humans are in the 40 to 70 percent range, but airline cabins are pretty dry. The humidity level can drop to 20 percent or even lower. That's drier than some deserts. 

And, of course, the air pressure on an airplane is much lower than when you're standing on the ground. The cabins are pressurized (otherwise you'd have a very hard time breathing), but the pressure during a typical plane ride is about the same as standing on top of a 2500 meter mountain. This combination of dryness and low pressure usually leads to xerostomia, less formally known as "cotton mouth." 

A dry mouth has less saliva in it, which can lower your taste buds' sensitivity by about 30 percent, making it harder to taste anything, especially sweet and salty foods. And it's not just your mouth that dries out, your nose does too, making it harder to sniff out odors. And smell can be  a huge component of flavor! So, not being able to taste much is hard enough, but when you add in the impact on the ability to smell your food on an airplane, well it's hard out there for an airline chef.

Finally, and also kinda strangely, sounds can have a lot to do with taste. Some studies have found that people who eat in noisy environments rate their food as less salty and less sweet than people who eat in complete silence. Scientists aren't totally sure how noise changes the way things taste, but it might have something to do with how a nerve called the chorda tympani reacts to certain sounds. It runs from the taste buds at the front of your tongue to your middle ear. So a constantly humming jet engine, not to mention crying babies, chatty neighbors, and rattling drink carts, might also make plane food taste more bland.

However, not all flavors get affected in the same way. Sweet and salty foods don't pop as much in the sky, but researchers have found that other flavors taste basically the same and, in some cases, even stronger than they do on solid ground. Tomato juice, for example, is an in-flight favorite. Lots of people who aren't a fan of the red stuff on the ground, describing it as earthy and musty, have no problem ordering it in the air, where they say it tastes cooler and fruitier. That's led some scientists to think that, in noisy environments, the umami, or savory taste, is actually enhanced. Tomatoes are rich in umami, so that's why tomato juice and Bloody Marys might taste better to you in the air than on the ground.

So the next time you're offered one of those food trays, it might be worth asking for a nice, fresh glass of tomato juice to help wash it down.

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