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A ‘Magnetic Tongue’ to Sample Tomatoes

A mechanized tongue probes its way into yet another industry.
November 2, 2011

Researchers at the University of Copenhagen, led by Anders Malmendal, have developed a “magnetic tongue.” If that doesn’t exactly sound like something you’re apt to put on your Christmas wish list, that’s probably because you don’t work in the tomato-canning industry, which apparently could have a great use for such a thing.

New Scientist reports that Malmendal and some colleagues set out to replicate the ability of a human taste tester, who can rate texture, flavor, and consistency on a numerical scale. In order to create his magnetic taster, Malmendal et al. first analyzed the chemical composition undergirding the taste in 18 different varieties of canned tomatoes, something they achieved by scrutinizing the tomatoes’ hydrogen atoms using nuclear magnetic resonance spectroscopy (or NMR, for short).

It turns out that the location of hydrogen atoms in certain sugars and amino acids act as a kind of signature for those molecules, which in turn are correlated to a tomato’s taste: its saltiness, sweetness, and bitterness. With the magnetic tongue, production of canned tomatoes (and, presumably, in the future, other fruits or vegetables) could be sped up, with factories adjusting their ingredients on the fly to fine-tune the ideal canned tomato taste. “NMR has many advantages,” Malmendal tells Technology Review. “The samples do not need to be preprocessed, it is rapid and has a low cost per sample (once you have an NMR spectrometer) and easy to get a quantitative output. There is for example a commercial NMR-based orange juice analyser that can verify the juice’s authenticity, but so far it does not deal with the taste.

The team wrote up their findings recently in the Journal of Agricultural and Food Chemistry. “The story behind [the study] is actually quite coincidental,” Malmendal tells me. “Antonio Randazzo who is now at University of Naples is an old colleague. A few years ago we were looking for a project together. Antonio’s wife Claudia was working with sensory analysis at the time and had some canned tomato data, so Antonio got the same tomato cans as she had been working with and ran NMR spectra on them, and we started to look at the data.”

This isn’t the first mechanized gourmand this blog as turned its attention to. In August, we were cheered to learn that the robots of the future would have fine taste in wine, given that a Barcelona-based research team had replicated some of the abilities of the sommelier in electronic form.

Robotic tongues have been put to a lot stranger use. Back in April, DigInfo spotted this robotic “kiss transmission device.” Is there also an uncanny valley when it comes to simulated tonsil hockey, I wonder? Even the researcher in this video is unable to demonstrate it without cracking up.

What do you think is the more likely future of the robotic tongue–to streamline production in the food and wine business? Or to provide newer and ever stranger ways for lonely people to be less lonely? Both are robust markets.

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