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Everyone has preferences when it comes to their food, but what happens when your next meal responds?
That uncomfortable question is at the center of a new study by a team of researchers at Japan’s University of Electrocommunications. To answer, they created one of the only known edible robots in the world, something they clinically refer to as an edible agent (not to be confused with an edible arrangement, the popular fruit basket). In the experiment, the team wanted to see if they could shape how onlookers perceived the robot by altering its behavior, and then see if that perception made people more reluctant to eat the little guy. The findings were recently published in the journal PLUS one.
The consumable part of the robot is made of a gummy candy-like material sweetened with sugar and apple juice. It is connected to a pneumatic system that pumps air through internal chambers to make the robot move. The resulting pulses and thrusts resemble a mini version of the inflatable air puppets with long, wavy heats you see at used car dealerships. A hidden speaker allows the robot to vocalize, in this case speaking Japanese in one scenario and crying like a cranky baby in another. Tiny arms and black dot eyes were added to enhance the weird factor.
Video 2 (Low A, High E)
A talking ‘god’ robot and a crying baby
About 1,000 participants watched two videos showing a researcher interacting with the robot. The first video was designed to present the robot in the role of “strict god or mentor.” An off-screen researcher consults the robot about his personal problems. With the camera focused on its glowing eyes, the robot responds with a deep, emotionally flat Japanese voice generated using speech synthesis software. While talking, the robot rocks back and forth.
The second video was more disturbing. The robot no longer speaks with an adult voice, but instead sounds like a helpless baby. When a researcher waved his hand, the robot responded with a playful laugh. When they approached him with an inflatable toy, he made a frightened sound. When approached repeatedly, the robot became angry. The sticky robot finally let out a sad hum as the researcher waved goodbye.
After watching the clips, presumably bewildered study participants were asked to answer a series of psychological survey questions designed to measure how much agency or expertise they attributed to the robot in each video. In psychology, agency corresponds to perceived control and the ability to make decisions. Experience reflects whether something seems capable of feeling emotions such as pain or joy. As expected, participants rated the Japanese-speaking robot as having more agency and the crying baby as having more expertise.
But then something contradictory happened. Having established that participants perceived the robot to have some kind of mind, the researchers asked whether they would hesitate or feel guilty about eating it. Overall, they didn’t seem to care. Participants were a little more reluctant to eat the talking robot, but not by much. Guilt was not an issue in any way.
So are humans ambivalent cannibals?
Before losing complete faith in humanity, some important caveats are in order. While the researchers asked participants how they would feel about eating the seemingly alive robot, no one actually had to do it. Consuming it was still theoretical. The sight and sounds of a rubber robot screaming in agony while being devoured for lunch would probably trigger some type of reaction.
Perhaps most importantly, none of the participants were physically in the room with the robot. The researchers note that conducting the experiment entirely online was a practical decision made to ensure a large enough sample size. While understandable, it is a limitation for a study whose central question involves something as inherently physical and visceral as eating. A much more illuminating experiment would be to ask participants to observe the robot in person, take a bite of it, and then perform its autopsy.
Curiously, something similar has already been done with this same robot. A separate 2024 article introduced the edible robot and used it to explore the psychology of eating things that are still in motion. The practice is common enough in Japan to have its own word: odorigui or “eat while dancing.” In that experiment, 16 students at Osaka University were asked to put the edible robot in their mouths while it was still moving and let it dance for 10 seconds before taking a bite. When asked how they felt afterwards, participants tended to feel more guilty about eating it the more the robot moved.
The key difference between the robot in that study and the most recent one is the introduction of vocalization and the addition of arms and eyes to make it appear more realistic. But those additions only go so far when they’re muted by the distant sterility of a computer screen.
Still, researchers are optimistic that they have found something with this unique little robot. Future versions could be expanded to represent a broader range of animals, possibly opening the door to exploring the psychology and ethics of why some people and cultures refuse to eat creatures that others consider perfectly acceptable. It could also be used to examine human attitudes toward novel foods such as lab-grown meat and gene-edited mushrooms, which are being presented as potential solutions to food shortages as global populations and appetites grow.
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