â€œAirline foodâ€ is hardly a phrase that has conjured thoughts of haute cuisine, or even digestible cuisine for that matter. No one really expects to dine elegantly or joyously when on a flight but if airlines take on the findings from a new study, the food you are offered on planes may soon taste better.
In the new study, 48 participants in a crossover experiment sampled drinks that contained the five basic tastes; sweet, sour, salty, bitter, and umami. Umami is is a Japanese word meaning â€œsavouryâ€ or â€œmeatyâ€ and applies to the sensation of sweet savouriness in foods, specifically, to the detection of the amino acid glutamate, which is especially common in meats, cheese and other protein-heavy foods. The action of umami receptors explains why foods treated with monosodium glutamate often taste fuller or just better, even though they are not better for you. The subjects tasted the drinks either in conditions with normal noise or in the presence of noise similar to what is experienced when flying on an airplane.
Airline cabins are an unusual environment, in which food is consumed routinely under extreme noise conditions, often over 85 decibels. The subjects rated the intensity of the taste for the drinks they sampled.
The results showed that no difference in intensity ratings was evident between the control and noisy condition for salty, sour, or bitter tastes. Similarly subjects did not perform differently during sound conditions when rating tactile, visual, or auditory stimulation, or in reaction time tests. However, sweet taste intensity was rated progressively lower in the presence of noise as noise incresaed, whereas the perception of umami taste was heightened as noise increased.
This effect probably occurs due to stimulation of the chorda tympani nerve, which transits directly across the tympanic membrane of the middle ear. The chorda tympani is a bilateral branche of the facial nerve (cranial nerve VII) that innervates taste buds in the anterior two thirds of the tongue and part of the soft palate and throat.
What this study shows is that taste is a complex phenomenon depending on many environmental factors. We know that as well as taste bud stimulation, taste also arises from other sensory inputs like the touch or feel of the food, colours around the food, and now the sounds around us as well.
The study also makes sense of findings by the Germam airline Lufthansa that passengers consume as much tomato juice as beer on flights. Tomatoes are, you guessed it, an umami tasting food.
In the end, it all explains why airline food is on the noseâ€¦or should that be â€œin the earâ€?