Airline food has suffered for years as the butt of the joke, commonly characterized as bland and passable at best. There's a scientific explanation for why sky-high meals feel so lacking, however,and illuminates the special challenge airlines face in combatting the problem. From the time you take off, you're settling into a low-humidity environment that dries out the nasal passage and significantly reduces the power of your taste buds.
Blame these tiny taste receptors and their dependence on your sense of smell, coupled with the depletion of saliva for the lack of wow factor in high-altitude food. “What most people consider taste is really more flavor, of which the vast majority is really from olfaction—or the sense of smell," says Doctor Gene Liu, an Otolaryngologist at Cedars Sinai Medical Group. "Our taste buds are little chemical receptors in the mouth and throat and predominantly on the tongue that sense sweet, sour, bitter, salty and umami when partially broken down foods within the saliva come into contact with the receptor cells. An electrical signal is then transmitted to the taste centers within the brain along specialized nerves."
There are several factors that affect the conditions inside an airplane and render it so dry—recirculated air and dust particles primarily—and therefore, the congestion this causes, says Liu, "decreases our ability to appreciate the flavor of the food."
Each flavor type has its own section on the surface of the tongue: Salt and sweet at the front, sour at the sides, and bitter at the back. Eating in a plane at high altitudes, coupled with the low humidity in the cabin significantly reduces the ability to taste the more subtle components of a meal. A dryer mouth can't experience the flavors as well due to the reduction in the saliva needed to taste flavors. "When we bite into a steak, if we have a diminished sense of smell, we would still be able to taste the salt, but there would be less 'steak-ness' to the steak," adds Liu.
Knowing how to master ingredient combinations helps combat the challenges of creating flavorful inflight meals. In their book, "The Flavor Bible" Karen Page and Andrew Dornenburg describe how each taste affects the other—"...bitterness suppresses sweetness...Saltiness stimulates the appetite, while sweetness satiates it..." in a way that may enlighten the average flyer looking for a tastier meal in flight. Understanding how to combine these tastes for this unique eating environment contributes to creating a balanced, flavorful dish.