Recording and reproducing taste

In 1877, Thomas Edison invented the gramophone and became the first person to record and reproduce his own voice. In 1895, the Edison Company created one of the earliest sound films – a 17-second clip in which one man played a violin while two others danced nearby. In other words, it has been possible to record and play audio and visual scenes for 125 years with reasonably high fidelity. But throughout human history, there has been no way to capture and reproduce the taste of food or drink – that’s until last year with the arrival of Homei Miyashita’s ‘Taste Display’. The invention of Miyashita, a scientist at Meiji University in Tokyo, is a 21^st-century analog of a gramophone – one that plays flavors rather than sounds.

Miyashita has a longstanding interest in food and taste. His curiosity about ingredients was piqued as a child when his mother wrote a recipe book. He has done his own research at Meiji University as one of the founders of the Frontier Media Science program, which explores the interface between technology and the human senses. In 2012, he and former PhD student Hiromi Nakamura (now at the faculty of the University of Tokyo) developed an ‘electric fork’ originally intended to enhance the taste of hospital food – the idea was to make food taste salty, for example. without actually adding salt, thus avoiding possible adverse health effects.

That was an early step for Miyashita, who had bigger, more ambitious plans. While the electric fork could make food taste salty or sour, the Taste Display could reproduce each flavor you may want to evoke. Here’s how it works, starting with a little anatomy: The human tongue has separate receptors for detecting the five basic tastes: sweet, sour, bitter, salty, and umami. Miyashita’s device has five different gels, each with an electrolyte solution that makes the tongue feel one of those flavors on contact with the surface with an intensity that can be easily adjusted. Each gel is associated with a separate (extremely weak) electrical current, and the flavor associated with that gel decreases as the current is increased. Also included is a sixth, tasteless gel as a buffer that keeps the overall flow level – and the accompanying tongue stimulation – constant at all times.

By adjusting the current strengths for all six gels, which can be done automatically, the taste of a chocolate milkshake or an entrecote or any other desired treat can be experienced using this device without any calorie intake.

The flavor display was initially shaped like a bar that resembles a handheld microphone with a surface designed to be licked rather than talked to. But Miyashita already has an early version of a mask, which provides a user with continuous contact with the flavoring surface as part of a virtual reality system. He has also developed a ‘lickable screen’ that can be integrated into a mobile phone, so that someone can, for example, watch a cooking show while tasting different samples.

“Or someone looking at a recipe on a website can find out what that dish tastes like,” he says. “We now have smartphones with cameras, screens, microphones and speakers. But soon we will be able to move on and upload and download our taste experiences. “

That’s a brief introduction to the flavor reproduction portion of the story, but what about incorporating things? Miyashita currently uses commercially available ‘taste sensors’ that provide a quantitative measure of the five flavor components of each food sampled. He developed equations that convert that flavor data into a corresponding amperage for each of the five flavors.

Today’s taste sensors are bulky machines that are rather slow to deliver results. Miyashita is exploring faster, more portable ways to capture flavor – perhaps using a thermometer-like device that can be dipped in food, allowing for quick readings of the different flavor components. A portable “salt meter” like this already exists, and it could be adapted to measure other flavors as well. He predicts that within ten years we should be able to immediately register and reproduce taste information.

However, food is about more than just feeling the five basic flavors in their countless combinations. Scent is also an important part of the taste experience, and Miyashita is already experimenting with ‘scent displays’. He also examines the sense of touch and how a particular food feels in your mouth. To this end, he is working on 3D printing, using not only smooth plastic, but also a range of materials with varying degrees of roughness. “By combining that with our taste research,” he says, “we hope to reproduce the texture you feel while eating.”

“But you can only do so much,” he admits. ‘You could watch a travel video, but that probably doesn’t mean you don’t want to visit a foreign country. Nor would listening to a record necessarily satisfy your urge to hear live music. And so it is with taste. Technology can, of course, do amazing things – his lab is an excellent example. But there’s also something to be said for a good home-cooked meal, says Miyashita, perhaps taken from the pages of his mother’s recipe book. .