This artificial ‘tongue’ measures how spicy food is before it hits your bare mouth

Don’t take a licking from spicy food.

A team of researchers in China claims to have created an artificial “tongue” that can quickly detect spice levels in their food — and they used a well-known gustatory hack to do it.

The taste-testing device resembles a small, transparent square of soft gel that the consumer places on their tongue — ready to taste-test meals before diners dive in.

“Our flexible artificial tongue holds tremendous potential in spicy sensation estimation for portable taste-monitoring devices, movable humanoid robots, or patients with sensory impairments like ageusia, for example,” Weijun Deng, the study’s lead author, said in a statement.

The prototype, reported in the journal ACS Sensors, took inspiration from milk’s casein proteins which latch onto capsaicin, the compound that makes chili peppers burn and tingle.

Researcher Jing Hu and colleagues based their research on the fact that capsaicin, the molecule that causes the hot sensation in foods like peppers, can be neutralized by milk’s casein protein. So, they set out to create an artificial tongue that adds casein to an electrochemical gel material.

That invention would be able to measure spiciness levels through an electrical current change that occurs when casein binds to capsaicin.

When researchers incorporated milk powder into a gel sensor, it was able to detect capsaicin and pungent-flavored compounds.

To create the tongue-shaped film, researchers combined acrylic acid, choline chloride and skim milk powder, then exposed the solution to UV light, resulting in a flexible and opaque gel that transmitted an electrical current.

Researchers tested eight pepper types as well as eight spicy foods, including hot sauces, on the artificial tongue and measured how spicy they were based on the changes in the electrical current.

Ten seconds after adding capsaicin on top of the film, the current decreased, which revealed the film as a potential spice-detecting artificial tongue.

The material responded to spice concentration levels ranging from below human detection to beyond levels perceived as painful.

It was also able to detect other pungent-flavored compounds commonly found in hot sauce ingredients, including ginger, black pepper, horseradish, garlic and onion.

A panel of taste testers rated the same spices and peppers on a level of spiciness, and results from the artificial tongue matched well with the tasting panel.