Electrode recreates all four tastes on your tongue

New Scientist

An electrode that can produce the taste of salty, sweet, bitter and sour food could make gaming tastier and help in healthcare too

LIFE in virtual reality could soon get a whole lot tastier – now a digital simulator can transmit the taste of virtual food and drink to the tongue. This might mean that gamers and VR explorers will be able to sample something of the food appearing on their VR headset or computer screen.

The synthesiser was developed by a team led by Nimesha Ranasinghe at the National University of Singapore, who thinks that one day TV viewers will be able to taste the food in cookery shows, too.

Signals that reproduce the four well-known major taste components – salt, sweet, sour, bitter – are transmitted through a silver electrode touching the tip of the tongue. The taste receptors are fooled by a varying alternating current and slight changes in temperature controlled by semiconductor elements that heat and cool very rapidly.

"We have found noninvasive electrical and thermal stimulation of the tip of the tongue successfully generates the primary taste sensations," says Ranasinghe. The device is a little clunky at the moment, but redesigning it will mean it can be in contact with the tongue when the user's mouth is almost closed. It was presented at the ACM Multimedia conference in Barcelona, Spain, last month.

Ranasinghe also foresees healthcare applications for his device. "People with diabetes might be able to use the taste synthesiser to simulate sweet sensations without harming their actual blood sugar levels. Cancer patients could use it to improve or regenerate a diminished sense of taste during chemotherapy."

The team is also working on a spin-off called a digital lollipop that will give the effect of a continuous sugar hit – but without sugar. For taste messaging they have developed TOIP – taste over internet protocol. This is a data format that makes it easy to transmit information on how to recreate the different tastes via the electrode.

It is early days. The four major taste components, plus the fifth, the savoury "umami" tang, are only a part of what we call flavour. Smell and texture are important, too – and the team now wants to work on adding those effects.

"In a gaming environment we could come up with a new reward system based on taste sensations," Ranasinghe says. "For example, if you complete a game task successfully, or complete a level, we can give a sweet, minty or sour reward. If you fail we can deliver a bitter message."

It could also be used to wean people off sugary drinks, says Jennifer Cornish of Macquarie University in Sydney, Australia. Last week her group warned that overconsumption of such drinks could cause changes in the brain that might lead to Alzheimer's and cancer. "A taste simulator might help extinguish or reduce the physiological effect of drinking sugar, however, the psychological factors of sugar enjoyment would remain," she says.

This article appeared in print under the headline "That tasty tingle"