A New ‘Electronic Tongue’ Can Detects Wine Spoilage Accurately

It’s axiomatic that wine is alive, and that it lives within in its process of becoming what we want it to be. That makes wine a fellow traveler and a fine mirror of all other living things, and that’s arguably one of the many good reasons the Romans invented the god Bacchus and put him in their pantheon to rule wine and its many illuminating — and some not so illuminating — effects on us.   

When a wine’s life process is going as it should, we enjoy it and celebrate it at its chosen point on the spectrum of its maturation. But as a living medium motoring along within that grand process, wine can be attacked and broken by a host of biological forces, such as certain bacteria, that have radically different ideas and uses for wine than we do. Put a different way, as a living thing, over time wine can become prey to a series of natural predators — and that’s part of the risk in which we engage when we make life and try to put it into a bottle.   

Famously, tooth-and-nail, winemakers fight this spoilage 24/7/365, and they have done that for centuries. Testing wine demands extremely detailed manual labor, not to mention outlay. Many testing methods have been spun off the last half-century’s digitization, most notably and recently, the so-called “electronic tongue,” a device with a series of digital sensors that can be instructed to detect — much more quickly and accurately than any human palate or olfactory system can — whether red wines are “infected” with a range of organisms that will cause spoilage.   

Now, thanks to a team of scientists from Washington State University, a range of white wines have been put through the electronic tongue in a rigorous series of tests that compared its accuracy and response times to those of a panel of (trained) humans.   

To spoil the plot of the experiment in the service of celebrating it, the electronic tongue won the test hands-down, detecting as early as seven days in, in other words, as the attack was in its infancy, that there would be a taste-killing bloom of one sort or another. In essence, the test was about the nose, or more specifically, whether and how early the trained human panel could smell four top sorts of spoilage compared to the electronic tongue’s data-driven analysis of the presence of the (known) chemical traces of those natural bacteriological wine predators.   

To give us a sense of the thoroughness of the study, two of the more entertaining wine predators with which the WSU scientists chose to inoculate bottles were Acetobacter aceti, which makes wine smell like vinegar, or, as quoted by the study, “fingernail polish remover,” and  Lactobacillus brevis, which can give wine what vintners describe as a “mousy” smell.   

That means that we should most heartily salute the brave WSU human panel who underwent weekly bouts of competition against the machine as the inoculated wine matured over the course of the 42-day test because they were trained by sniffing (used) mouse bedding, and nail polish remover, among other things, in order to refine their noses to compete with the electronic tongue.  All in valiant service to preserving, and building, a trustworthy early-warning system for spoilage.  

In all wine production, such a clear, irrefutable warning system would have great value to the maker, but in white wine production, the value would be amplified since white wine production generally happens at far greater velocities than does the production of reds, thus increasing the velocities of the decision-making faced by makers by orders of magnitude. Days, or in some cases hours, can matter in white production. Not that they don’t face a super-grueling grind of their own, but makers of reds don’t usually have that gauntlet to run.   

Bottom line, according to the scientists at WSU, if you’re opening a well-iced and well-deserved bottle of dry, well-balanced Riesling and it smells like a mouse, or some moss, or a something-wet instead of something-dry, give a salute to that wine’s valiant battle in life, and crack a different one.