What does coffee sound like? Maybe…a coffee pot making coffee. Or perhaps the Folger’s jingle. But that’s not what the taste of coffee actually sound like. What is that sound—the taste of coffee?
It’s not just a question for synesthetes. Researchers are trying to use sound to quantify taste. Edible Geography writes about the challenges that food scientists have had in really measuring what something tastes like and about a new idea for that sense:
n a paper to be published in June 2013 in the journal Food Hydrocolloids, scientist George A. Van Aken of NIZO, a Dutch food research company, reveals a new method of measuring mouthfeel: the wonderfully named “acoustic tribology.” Van Aken took a tiny contact microphone, packed it in polyethylene to keep it dry, and secured it behind a test subject’s upper front incisor teeth in order to record the acoustic signal produced by the varying vibrations of their papillae as their tongue rubbed against their palate.
In short, Van Aken’s device means that we can now listen to what our tongues feel.
Flavor scientists call that sensation on our tongues is “mouthfeel.” Normally, mouthfeel is reduced to subjective descriptions: velvety, rough, cohesive, hard, heavy. But with Van Aken’s device, scientists can listen to precisely what your mouth is feeling. Here’s a little more about how it works:
The process works by picking up vibrations within tongue tissue, which vary depending on the amount of deformation the papillae experience when rubbing against the palate. To return to our initial experiment, you can actually listen to a recording of the feel of black coffee (mp3), and then compare it to the softer sound of the feel of coffee with cream (mp3) or hear them both back-to-back in this NIZO video (wmv) — from sawing wood to depilling a sweater, and back again, interrupted by an occasional higher-pitched pop (apparently, these are caused by the “snapping of salivary films and air bubbles at the papilla surfaces”).
The results give us more than just a measurable signal for mouthfeel, too. Take coffee. If you put milk in your coffee, it tastes one way. If you take it black, it tastes another way. What Van Aken found that at first, milk has a loud signal, but then later it wears away. Basically, Edible Geography says, “everything tastes creamy when your tongue is worn out — which perhaps lends weight to the Victorian advice to chew each mouthful one hundred times before swallowing.”
Understanding why certain things taste the way they do can pave the way for making artificial foods mimic the real ones. Products like vegan cheese and fake meat can often mimic a taste of a food, but not the way it feels in your mouth. And as anyone who’s ever tasted vegan cheese can attest, it makes a difference.
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