Analytical chemistry says that Scotch whiskys really are different

Short: The Scotch industry has new scientific evidence that different single malts and blended Scotch whiskys are complex and distinctly different from one another. (Unlike, the suggestion might be, some mass-produced American “craft” whiskeys.)

Long: You can learn a lot about a field by its acronyms. Acronyms arise for awkward word-strings that a certain flavor of professional uses often but everyone else uses infrequently enough for English not to have a better and less cumbersome word for whateveritis. Winemakers talk about MOG: Material Other than Grapes.* MOG is interesting because winemakers are generally trying to get rid of it. Mass spectrometry experts talk about NOM: Natural Organic Material. Wine is a NOM. NOM is interesting because it’s replete with myriad compounds at miniscule concentrations and therefore helps spectrometer-ers figure out how good their techniques are. Mass spec is interesting to NOM-lovers because its a good way to learn about the composition of the NOM. And who are NOM-lovers? You are. Wine is a NOM. So is whisky.

A batch of analytical chemists from Scotland has just published a new article (open-access) in the Journal of the American Society of Mass Spectrometry (no, I didn’t know that existed, either) applying a particularly sensitive and wide-seeking version of mass spectrometry (more detail on what that means below**) to quantify the complexity of single malt and blended Scotch. Across 85 different commercial whiskies, they found 4271 unique molecular fingerprints – not precisely the same as identifying 4271 unique molecules because of the kind of data mass spec generates, but definitely evidence that whiskies are very, very complex mixtures. Only 407 of those probably-molecules were common to every whisky, and only about a thousand were common to 75% of the samples. In short, whiskys are highly variable, and perhaps even more complex than you’ve been imagining.

That result should please the SWRI – an acronym you’ll recognize if you’re in the spirits trade and that I should otherwise explain stands for the Scotch Whisky Research Institute – who provided funding for the study. A cadre of American “craft” whiskeys have been attacked from many quarters (including NPR and Serious Eats) for being remarkably similar across brands and price points and, not unrelatedly, for originating in the same industrial production facility in Indiana. Funding analytical chemists in Edinburgh looks like a Scottish move to assert that Scotch is the real deal, and maybe that consumers’ money is well-spent trying honest-to-goodness different brands.

That implication brings us back to the NOM. For the chemists, the choice of NOM isn’t precisely inconsequential – I know that the lead author on this paper is a NOM-lover himself, and they obviously wouldn’t have won funding from the whisky industry if the lab was studying, say, latex wall paint. But this study is published in a journal of mass spectrometry, and at least a large fraction of the point here is about demonstrating the prowess of their hardware and analytical methods. And that point has to do with the kind of data this study provides. We know that whiskys contain a lot of unique molecules, and we know that different whiskys contain lots of different molecules. What we don’t know is anything about how or whether those molecular differences translate to sensory differences. But since the SWRI is interested in Scotch, not just in NOMs, I suspect that we may be seeing that sensory study soon.

 

* Material other than grapes that ends up in collection bins with grapes, not all non-grape matter everywhere; winemakers might get accused of singlemindedness, but they’re not that bad.

**Mass spectrometry, broadly speaking, is a method to identify chemicals by their mass which, given that every kind of atom (think the periodic table) has a unique mass and molecules are defined by their atomic composition (and how those atoms are arranged, which makes life more complicated), makes mass spec something approaching a molecular fingerprint. Mass spectrometry, narrowly speaking, is any one of many, many different versions of that general principle, all of which have their own acronyms. These folk sent their 85 samples of fine Scotch through ESI-FT-ICR MS, which means electrospray ionization-Fourier transform ion cyclotron resonance mass spectrometry, which means that the scientists didn’t have to decide in advance which compounds they wanted to look for.

Have we domesticated yeast? Yes.

Common sense says that winemakers – and beer brewers, and bread bakers – were developing specialized Saccharomyces cerevisiae yeasts a good long while before Red Star marketed its first dried and packaged commercial product to the industry in 1965. Winemakers weren’t inoculating ferments with an aluminum foil packet they bought at the store, but that doesn’t mean they weren’t inoculating, maybe with a little bit of an already-active ferment, maybe just by having a conducive winery environment where the right kinds of yeast were happy to make a home. Either way, the yeast you’d find in any given winery or brewery weren’t the same as the yeast you’d pick up off the street, or the same as what you’d find in the next alcoholic beverage factory down the road.

Plenty of evidence, old and new, supports that story. But did those yeast become different simply because they were isolated from each other, like Darwin’s famous Galapagos finches? Or did they change because they became domesticated, because brewers and winemakers cultivated and selected them? In other words, what kind of difference did the humans make to the yeasts’ evolution?

The theory basically goes like this. If yeast populations developed in different ways just because they were physically separated, then their genomes should look like what you expect from “wild” yeast. If humans domesticated them, they should be less genetically fit, because they’ve grown accustomed to being specially cared for and protected by humans and have lost some of their capacity to live on their own.

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The neurophysiological shape of wine expertise (and why reports that somms are Alzheimer’s-resistant are wrong)

Even if you think of your brain as a muscle, you probably don’t think about it literally bulking up as a result of exercise. It does, at least in some cases. Master sommeliers – professionals who we assume (and sure hope) have intensively developed senses of smell – have more white matter in regions of the brain associated with olfaction, according to new research (open-access) comparing images of master somm’s brains with those of randomly wine inexpert university students. Very similar patterns of brain-buffness have been found in the heads of professional perfumers.

There’s a funny paradox at play here. On the one hand, smell is probably the least understood of the senses – at least if we’re only counting the canonical ones. On the other, in part because it’s so little understood, smell is a favorite subject for this kind of study. You might suspect that smell is also useful for being simple and isolated from other elements of mental function. It’s not.

One reason for being interested in the brain’s anatomy of smell is to test the limits of neuroplasticity – how much our brains can change after we become adults. (How much can it change? A lot more than previous models of human development allowed.) At least in the United States, most wine experts will have learned their craft as adults. Another reason for smell-focused research is that olfactory regions are among the first to deteriorate in Alzheimer’s and Parkinson’s, to the extent that smell impairment is being considered an early warning sign of those diseases. That link is especially interesting in light of the mountain of scientific and lay-person evidence linking smell with memory.

I’m still waiting for the study investigating whether well-trained oenophiles have better memories or are less prone to Alzheimer’s. Which, contrary to reports by writers who actually earn salaries for their work, is not what this study did. This is observational research about neuroplasticity and developing expertise, about the capacity of the adult brain to change shape with training. No one investigated rates of Alzheimer’s amongst aging sommeliers. No one gave them memory tests. Certainly no one sat around and watched the somms who took part in this study into their retirement years to check up on their mental acuity. Even if they had, too few sommeliers were involved to make any kind of statistically significant judgment even about a disease that the US National Institute on Aging calls the sixth leading cause of death in the United States.

We can say that the effects of intensive sensory training are apparent on an MRI. We can’t say that becoming an expert wine-sniffer prevents Alzheimer’s. Not yet.