Bucking the “touchless” trend ina big way, researches at Meiji University in Japan have invented a “taste display” that can artificially recreate any flavor by triggering the five different tastes on a user’s tongue.
It was once thought that the tongue had different regions for tasting sweet, sour, salty, and bitter flavors, with concentrations of specific taste buds for each. It’s now know that the four main tastes spread out across the tongue, and the fifth flavor, umami, is important to enjoying how things taste. This better understanding of how the tongue works is crucial to a new prototype device that its creator, Homei Miyashita, calls the Norimaki Synthesizer.
Miyashita was inspired by other experiments that proved how easily our eyes can be tricked into seeing something that technically doesn’t exist–the microscopic pixels of red, green and blue that so much of our display-dependent industry is based on. Miyashita wondered if a similar “pixel” approach could be used to trick the tongue–that’s why the Norimaki Synthesizer is also referred to as a taste display.
The Norimaki Synthesizer uses five gels that trigger the five different tastes when they make contact with the human tongue.
As reported by my colleague at Gizmodo, the color-coded gels, made from agar formed in the shape of long tubes, use glycine to create the taste of sweet, citric acid for acidic, sodium chloride for salty, magnesium chloride for bitter, and glutamic sodium for savory umami. When the device is pressed against the tongue, the user experiences all five tastes at the same time, but specific flavors are created by mixing those tastes in specific amounts and intensities, like the RGB pixels on a screen. To accomplish this, the prototype is wrapped in copper foil so that when it’s held in hand and touched to the surface of the tongue, it forms an electrical circuit through the human body, facilitating a technique known as electrophoresis.
Electrophoresis is a process that moves molecules in a gel when an electrical current is applied. In this case, this process causes the ingredients in the agar tubes to move away from the tongue end of the tube, reducing the ability to taste them. It’s a subtractive process that selectively removes tastes to create a specific flavor profile–in this case the flavor of everything from gummy candy to sushi.