Scientists Built a Synthetic Tongue to See if Your Whisky is Legit

Many snobs will tell you it takes decades of work and expertise to be able to distill, identify, and appreciate a fine whiskey. But now with the power of science you can tell the good stuff apart from a cheap imitator in a matter of minutes. In research published Thursday in the journal Chem, a team of organic chemists from Heidelberg University in Germany outlines the creation of what they call a “synthetic tongue” that can compare and contrast two whiskeys down to the molecular level.

While calling the device a tongue is a bit of a stretch — it’s actually an array of glowing dyes that respond to the different chemicals found in whiskey — it functions in a comparable way to how our taste buds pick up on different substances and trigger a chemical reaction that tells our brain about a food or drink’s flavor.

The idea came to lead author Uwe Bunz when academic journals decided not to publish the process for synthesizing these polymer dyes that he developed two years ago, Bunz tells Inverse.

“When your papers are rejected, your start to think hard, what the potential of these polymers could be and what they could be used for,” he says.

Further results found that the dyes were good for detecting compounds like proteins and other biological agents, so he set to work developing an array. In his own way, Bunz turned to drink and started testing the dyes on whiskey.

“Whiskies are an almost ideal test bed for our tongues,” writes Bunz. In spite of the variety found in whiskeys based on flavor, ingredients, blends, age, and country of origin, the liquor is made up of compounds that are difficult to distinguish without either a sophisticated palate or chemical analysis.

After pouring some shots onto his tongue (and also his array) Bunz found that his device could not only tell the differences between two different whiskies but it could also group different whiskies by their differences. For example, single malt scotches had a different chemical signature from bourbons or Irish whiskey, and some water and fake whiskies that were thrown in as controls were easily isolated.

Bunz says that his synthetic tongue could be used to tell whether someone is trying to rip you off by labeling cheap whiskey as an expensive brand. But whiskey, as all great endeavors begin, is just the beginning. Bunz writes in an email that there are several different directions that he wants to expand his research, such as red wine tasting.

“It might be possible to look if similar Bordeaux wines can be differentiated and if one can differentiate a Saint Emilion from a Medoc of Pauillac. This could be then counter tested with wines from a discounter to check if their wines are really what they say they are.”

Bunz also envisions that his tongue could be used to weed out fake, expired, or heat-spoiled medications to make sure people are not only being prescribed what they actually need but also not taking drugs that have gone bad.

Since the technology for the synthetic tongue is readily available in an organic chemistry lab, home use might prove difficult. But Bunz suggests that anyone interested in forming such a whiskey watchdog company could get everything they need — including the polymer dyes from his own Heidelberg University — for the low, low cost of fifteen-thousand dollars. To be fair, that’s a small price to pay for anyone who wants to make sure that their one hundred forty-thousand dollar bottle of whiskey is the real deal.

Abstract:

In biology, non-specific interactions are ubiquitous and important, whereas in chemistry, non-specificity or non-selectivity is suspect. We present simple tongues consisting of fluorescent polyelectrolytes or chimeric green fluorescent proteins (GFPs) to discriminating 33 different whiskies according to their country of origin (Ireland, US, or Scotland), brand, blend status (blend or single malt), age, and taste (rich or light). The mechanism of action for these tongues is differential quenching of the fluorescence of the poly(aryleneethynylene)s or the GFPs by the complex mixture of colorants in the whiskies (the interactome), extracted from the oak barrels and added coloring. The differential binding and signal generation of the interactomes to the polymers and proteins result from hydrophobic and electrostatic interactions. The collected quenching data, i.e., the response patterns, were analyzed by linear discriminant analysis. Our tongues do not need any sample preparation and are equal or superior to state-of-the-art mass spectrometric methods with respect to speed, resolution, and efficiency of discrimination.