I am sitting at my kitchen table eating chocolate in the name of science. (Turns out I am pretty good at science). I am trying out some “sonic seasoning” whereby if I listen to a low-pitched sound, my taste awareness somehow shrinks to the back of my tongue and focuses on the chocolate’s bitter elements. When I switch to a high frequency, the floodgates to sweetness open up and my entire mouth kicks back in a warm, sugary bath. It is a curious sensation because it does not feel, to me at least, as if the chocolate tastes different.
It is more that the sounds are twisting my gray matter, changing how it perceives the taste.
The sound is what sensory science nuts call modulating taste, and the past few years have seen a boom in research in this area.
Sound is the final frontier in food presentation. Restaurants agonize over menus, crockery, furniture and lighting, yet often any old CD will be stuck on background music with nary a thought. However, now that we are starting to understand that everyone has synaesthetic tendencies when it comes to taste, sound is set to play a bigger part in our eating experience.
Ben & Jerry’s, for example, is considering a sonic range of ice-cream flavors, with QR codes on the tubs that will allow eaters to access complementary sounds via their phones.
Back in 1997, British chef Heston Blumenthal introduced his iPod-enhanced seafood dish, Sounds of the Sea, but that was a more literal, more Pavlovian association: eat fish, listen to the sea, fish tastes fresher and better.
However, a number of recent experiments have shown how abstract sounds can turn tastes up or down by remote control, as it were.
The Crossmodal Laboratory at Oxford University fed a group of volunteers some cinder toffee while playing them high and low-frequency sounds, and asked them to rate the taste on a scale running from sweet to bitter.
Just as I experienced in my kitchen, high notes enhanced sweetness and low brought out the bitter. However, a laboratory setting is far removed from real life, so Charles Spence, who runs the lab, collaborated with food artist Caroline Hobkinson to test whether the results would be replicated out in the field.
For one month, London restaurant House of Wolf served a “sonic cake pop” of chocolate-coated bittersweet toffee, which came, intriguingly, with a telephone number.
On the other end of the line was an operator instructing the diner to dial one for sweet and two for bitter, and they were played the high and low-pitched sounds accordingly.
Hobkinson said: “It makes me laugh because it works every time, and people say, ‘Oh! That’s so weird!’”
She put on a similar event at the Royal Institute in London for which, instead of playing the synthesized sound clips, the Royal Academy of Music devised some abstract live performances that would do the trick with more feeling.
“It works with coffee, too,” she added, and she foresees exciting possibilities such as sound replacing sugar in your morning espresso.
Meanwhile, another study by Spence also matched the savory taste, umami, with low pitches.
Confirming the hunches of so many ravenous airplane passengers, a study published in 2011 found that loud background noise suppresses saltiness, sweetness and overall enjoyment of food. (For flyers, this is compounded by the high altitude blocking nasal passages, and therefore access to aromas.)