The phrase "sharing a drink with friends" could soon have a whole new meaning thanks to researchers from the National University of Singapore (NSU). A team there has developed a way to capture and digitally transmit the flavor of a drink that is reproduced using electrodes to trick your tongue into tasting the sourness of lemonade when all you're really drinking is boring old water.

It's a sad fact of life that the tastiest foods and drinks are the ones that are bad for us, but clever workarounds can let us enjoy the taste of something without actually consuming it. The Edible Mist Machine puffs out inhalable clouds in over 200 flavors, from chocolate to bacon, and previous NSU research found that electrically stimulating the tongue in different ways can mimic the basic taste types of sweet, sour, salty and bitter.

Following on from that, a team led by Nimensha Ranasinghe wanted to test whether the taste of a specific glass of lemonade could essentially be "teleported" digitally, and what effect factors like color have on a person's perception of taste. Lemonade was chosen because it has a distinct taste, and one that can be fairly easily translated into electrical signals.

First, a sensor is placed into the real lemonade, which uses an analog pH sensor to measure the acidity (or sourness) of the drink, and an RGB sensor to capture its color. That data is then sent via Bluetooth to the "Lemonade Simulator" – a high-tech tumbler with an LED in the bottom and electrodes around the rim. The LED lights up the liquid in the same RGB color as the real drink, and the electrodes send controlled electrical pulses to the tongue to mimic sourness.

To test how well virtual lemonade stacks up against the real thing, the researchers had participants drink either normal lemonade or water with the digital taste of lemonade laid over the top – but didn't tell them which was which. People had to first guess how sour a given drink was, judging by its color – yellow, green or "cloudy" – and then rank how sour it actually was after tasting it. Each person tried three cups of real lemonade and three virtual ones, over two sessions.

By sight alone, the test subjects saw little difference between real and simulated lemonade when they were green or yellow, but interestingly, far more people assumed the virtual cloudy lemonade looked more sour than the real stuff. The team believes that's because the white LED is brighter, and people associated that with a more sour drink.

After actually tasting the beverages, the real lemonades were ranked consistently more sour than the virtual ones. The researchers suggest that the water might be weakening the electrical signals on the tongue, and cranking up the strength of those pulses could help close the gap.

That said, the results were similar enough that the team is confident that the real experience can be reproduced better, especially if other properties like smell, temperature and fizziness are taken into account.

It's not on the table yet, but the team says that future applications for this kind of technology could be to help friends anywhere in the world share the "flavor experience" of food and drinks, or to help people still enjoy things like soft drinks without actually guzzling all that sugar.

"In the future, we envision a cloud repository for people to share digital signatures of their beverages," the researchers explain. "This concept may also impact personal well-being by encouraging people to drink virtually flavored water rather than artificial soft drinks."

The research was published on the ACM Digital Library, and the team demonstrates the system in the video below.

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