This electronic tongue uses an ‘e-Taste’ system to replicate flavors such as cake and coffee, recreating the experience of taste in virtual reality.

Yizhen Jia at The Ohio State University and his colleagues have developed a new system called e-Taste. The technology is capable of sampling food and determining how to partly recreate the flavor in a person’s mouth.

This is accomplished by using chemicals that correspond with the five basic tastes: sodium chloride for salty, citric acid for sour, glucose for sweet, magnesium chloride for bitter, and glutamate for umami.

The gadget uses sensors to detect the levels of chemicals in food, convert them into digital readings, and send the values to the pump. The pump then pushes small quantities of hydrogels containing different flavors into a small tube under a person’s tongue.

“Those five flavors are already accounting for a very large spectrum of the food we have daily,” says Jia.

The team also noted the system allows flavors to be delivered to specific regions of the tongue, which they say could be used to investigate human taste perception.

To test the technology, researchers behind the project began by asking 10 people how well the device reproduced sourness on a five-point scale. Participants in the study were able to rate the sour intensities correctly around 70 percent of the time.

Next, the team tested whether the technology could replicate more complicated tastes such as cake, lemonade, fried eggs, and coffee. The team notes that one of the device’s limitations thus far is that it hasn’t been able to successfully recreate certain flavor pallets, such as spiciness and fatiness.

Once these flavors were developed, the researchers asked a group of six people to test whether they could distinguish which flavors corresponded with which foods. The results showed the subjects could distinguish which flavors represented which foods almost 87 percent of the time.

However, the technology does have limitations. For example, it’s not yet capable of simulating other aspects of biology that influence taste, such as smell. And according to Alan Chalmers at the University of Warwick, UK, focusing solely on flavors won’t yield accurate results.

“Next time you have a strawberry, close your nose and eyes. A strawberry is very sour, but it is perceived as sweet because of its aroma and the red color. So if you send just sour across with their device, you will never know that it is actually from a strawberry… An e-tongue such as this is able to extract the amount of sweetness [and] sourness, but not taste as a human tongue perceives them,” Chalmers stated.