You’re familiar with the saying “You eat with your eyes first,” meaning of course that the good, or bad, visual aspect of food affects its appeal even before it passes our lips and into our mouths. The Chinese have a proverb, “You eat first with your eyes, then your nose, and then with your mouth.” It’s no surprise that our senses of sight and the smell of food impact our perception of flavor. Psychologists are finding that sound however, also augments or suppresses the taste experience.

Charles Spence, a sensory psychologist at Oxford University, conducted an experiment with sugar-sweetened candy, which also contained a touch of treacle – a slightly bitter-tasting molasses. Subjects tasting the identical candies listened to high-pitched or low-pitched music on headphones, and rated the taste. When listening to the high-pitched music, participants rated the candy as having a sweeter taste than the candy consumed while listening to the low-pitched tune. And the low-pitched music elicited ratings emphasizing the candy’s bitterness, even though it was the exact same candy.

Not only sound pitch, but loud sounds can amplify how good – or bad – a food tastes. This can help explain why airplane food stereotypically has been considered flavorless. And it perhaps even provides a solution as to how to overcome the bland food offerings on a flight. The tastelessness of airline food is attributed in part to lack of humidity and lower air pressure. The dry air of an airline cabin stifles our sense of smell which is an essential factor in taste.  But research shows that background noise can also suppress or enhance flavor perception.

In 2010, Lufthansa, a German airline, noted that tomato juice was a very popular beverage on their flights, with passengers consuming about 1.7 million liters each year. Investigating, the airline commissioned a study to simulate in-flight meals, becoming a pioneer in airplane cuisine research. Researchers built a special lab replicating cruising at 35,000 feet, dropping the humidity and air pressure and reproducing the engine noise. Results showed that the combination of dryness, low pressure and loud noise reduced the sensitivity of taste buds to sweet and salty foods. Sour, bitter and spicy flavor perceptions were virtually unaffected. The taste of tomato juice, however, was intensified.

Umami Improves Taste of Flavorless Airplane Food

How to explain this? The research suggests that foods such as tomato juice – with its bold umami flavor imparted by glutamate – not only withstand the negative impacts of loud noise, but is amped up by it, and can help change flavorless airline meals.

A loud noise study was performed by Cornell University to evaluate what happens to taste perception under varying noise conditions. Subjects first ate in silence; and then while wearing headphones listening to the sound of an airplane cabin recording played at 85 decibels, the median noise level during flight. Subjects rated the taste of weak, medium or high concentrations of sweet, sour, salty, bitter or umami solutions. Ratings ranged on a scale from “barely detectable” to “strongest imaginable.” Loud sound decreased detection of sweet flavors. Salty, bitter, and sour tastes were unaffected. Interestingly, perception of umami flavor was perceived as more intense under loud noise compared to silence. And the higher the concentration of umami, the stronger it was rated when loud noise was played. The researchers postulated that the effect is caused by a disturbance to the chorda tympani, the nerve that carries taste information from the tongue to the brain. The nerve crosses the tympanic membrane of the middle ear. Loud noises weaken sweet signals, and conversely heighten umami signals.

Airline kitchens have been experimenting with meal tests in simulated conditions or onboard planes to emulate what airline passengers may taste. Increasing the amount of salt and sugar can help, but can only carry flavor so far.

Celebrity chef Heston Blumenthal, proprietor of a Michelin three-star restaurant in Berkshire, England was charged with helping British Airways put the science of taste perception into practice. His restaurant, Fat Duck, is famed for “Sound of the Sea,” an oyster dish served alongside an iPod which plays the sound of waves lapping the beach, with a seagull squawking overhead, and increasing the taste profile of the seafood.

 Blumenthal first tried providing nasal spray to passengers to moisten and clear their sinuses before they ate. That, unsurprisingly, was a no-go. Resorting to umami, he developed, for example, a recipe for shepherd’s pie that featured glutamate-rich seaweed in the crust. United Airlines is using ingredients such as glutamate-rich spinach, tomatoes, and shellfish to up the umami taste. And Lufthansa is now adding more umami intense ingredients including tomato oils and tomato concentrate to their in-flight meals.

While most airline meals these days are served in first or business class, even those who fly economy can enjoy the heightened umami taste of food at 35,000 feet. Just order a beverage of tomato juice or a Bloody Mary. It will taste even better at lofty altitudes than it does on the ground!

 

References:

  • Crisinel A, Cosser S, King S, Jones R, Petrie J and Spence C. A bittersweet symphony: Systematically modulating the taste of food by changing the sonic properties of the soundtrack playing in the background. Food Quality and Preference. 2012. 24:201-4.
  • Michaels D. Test flight: Lufthansa searches for savor in the sky. Wall Street J. 2010. Accessed August 16, 2018. http://online.wsj.com/article/SB10001424052748703294904575384954227906006.html.
  • Spence C, Michel C and Smith B. Airplane noise and the taste of umami. 2014. 3: 2. https://flavourjournal.biomedcentral.com/articles/10.1186/2044-7248-3-2.
  • Yan K and Dando R. A crossmodal role for audition in taste perception.Journal of Experimental Psychology: Human Perception and Performance, 2015; 41 (3): 590. https://www.ncbi.nlm.nih.gov/pubmed/25775175.
  • Herz R. Why You Eat What You Eat. W. Norton & Company, Inc. New York. 2018. Pages 161-171.
  • Moskvitch K. Why does food taste different on planes? January 12, 2015. Accessed August 16, 2018. http://www.bbc.com/future/story/20150112-why-in-flight-food-tastes-weird.
  • Gajahan M. The Real Reason Why Airplane Food Tastes So Bad. August 14, 2017. Accessed August 16, 2018. http://time.com/4862996/airplane-food-taste-bad/.