You’ve made it just in time!

I was about to taste these crunchy cookies fresh from the oven.

They smell delicious!

Wait!

Something’s not right… oh!

I forgot to add the sound!

Much better!

I’m sure from your own experience you know that the way foods look, smell, and feel can influence your perception of what it tastes like.

But have you ever thought about how sound influences your perception of taste?

Crossmodal perception occurs when two or more of your senses interact with each other.

In the real world, this happens all the time.

Cooks at the family restaurant Chilli’s speak of The Fajita Effect, where one person ordering a sizzling, crackling skillet of fajita meat leads to an influx of fajita orders from other diners.

And we’ve even studied food sounds scientifically.

Researchers at the Crossmodal Research Laboratory at the University of Oxford wanted to answer the question, “Does changing the sound a food makes when you bite into it change your perception of its taste?” Their food of choice was Pringles!

They recruited 20 participants to bite into 180 Pringles each and asked them to rate each chip on its “freshness” and “crispness”.

With each bite, the researchers either played back to the participants the actual sound of the chip or modified the sound by adjusting the volume or frequency.

When the biting sound was louder or at higher frequency, participants reported the chips being significantly crisper and fresher.

And in Mary Roach’s book Gulp, Dutch scientist or “food physicist” Ton Van Vliet said, “To get this noise, you need to crack speeds of 300 metres per second.” The crunch of a chip is a tiny sonic boom inside your mouth.

Similarly, other researchers have found that foods that produce higher-pitched and louder sounds when bitten into, like peanut brittle, are described as crispier.

But are there sounds to make food more bitter, saltier, or even sweeter?

Could sound replace sugar?

Researchers have found that people can reliably match certain tastes with specific tones.

It’s known as “crossmodal associations”, People associate sweet and sour tastes with high-pitched notes...and umami and bitter tastes with low-pitched notes.

So, can changing the sounds in your environment while you eat a food change your perception of its taste?

In another study, researchers asked participants to taste pieces of bittersweet toffee and rate each piece on its bitterness and sweetness.

But with each taste, they either heard a soundtrack of low-pitched notes or a soundtrack of high-pitched notes.

You may have an idea of what these researchers found… Participants reported that the same toffee tasted more bitter when listening to the low-pitched soundtrack and sweeter when listening to the high-pitched soundtrack.

So, what we hear can bias our perception of the tastes already present in the food...like the bitter and sweet tastes of the bittersweet toffee.

But, we can’t use sound to create a taste that isn’t already present in the food… yet.

Only a very small number of people in the world experience tastes on their tongue when they hear different sounds without food.

They’re auditory-taste synesthetes and the theory is that in their brains, the regions associated with hearing directly or indirectly activate the regions associated with taste.

But what about the majority of people who are not auditory-taste synesthetes?

How are our brains processing sound and taste to create taste biases?

So far, researchers have found neurons in the brain that respond to multiple types of sensory inputs, but they're still investigating all the neural mechanisms underlying crossmodal associations.

Finding out why and how one of our senses can influence our perception of another sense can help us understand how we are able to navigate through the world – full of sounds, sights, smells, textures and tastes!

When you think about it, it’s pretty sense-ational!