I’ve been giving a lot of thought to yeast and barley lately (mainly because I’ve been reading a lot about brewing and distilling). Particularly, I’ve been thinking about how barley and yeast have developed over the years and how regional variations can greatly affect the flavor of whisky. When the ancestral distillers of malted barley first put flame to kettle, there was not much choice in ingredients. There was a local barley crop (malting on-site), a local water source, and wild yeast captured from the environment.
I like the idea of wild yeast; riding air currents looking for the right slurry of fruits or grains, gorging themselves on the precious sugars until their wanton gluttony causes them to choke on their own excrement (alcohol). I think there is a metaphor for the American financial system somewhere in that.
It seems so simple: barley, yeast, water. However, since the invention of refrigeration, distillers have been able to store and cultivate yeast strains.* This alone represented a huge step toward consistency of product and innovation. Not only could distillers be sure the same yeast was used each year, but they could tinker with a strain to get more of the qualities they found desirable (higher/lower alcohol content, more floral notes, less/more acidity, etc.). Any home brewer will tell you, the right yeast can have massive effects on your final product. Modern distillers go as far as patenting their yeast strains so no one can duplicate their product.
And what of barley you say? Well, barley has changed too. Distillers are no longer required to source barley from down the road. Modern transportation methods make shipping barley quite simple. Most Scottish distilleries use Scottish barley, but it’s sourced mostly from large-scale facilities that service multiple distilleries and offer several varieties of grain. However, several things are happening right now. There are a handful of distilleries experimenting with barley traditionally used for brewing beer (The Glenlivet Nadurra Triumph, for one). There are experiments in malting (some of the malt in Glenmorangie’s The Signet is roasted in a tumbler like coffee beans). Additionally, barley can be tinkered with in the same way as yeast. Scientists can build it stronger, heartier, sweeter. We have the technology.
When we are talking about whisky, we can’t leave wood or water completely out of the equation. However, I think we sometimes forget the importance of barley and yeast. I’m willing to bet that if you gave ten distilleries all the same water and a first fill bourbon barrel (all from the same distillery), you would still get ten distinct products. Somebody contact the SWA. I think we have a contest on our hands.
Of course, I’m leaving out the size and shape of the still and the unique environmental conditions of the warehouses, but you get the idea.
This was supposed to segue into a discussion about a tasting I recently lead, but I’ve somehow gone off track. Oh well, such is life. I think I’m going back to my books for now. Or maybe I’ll hit the streets with a tub of grain slurry and hope for the best. Do you need a butterfly net to catch wild yeast?
-Matt
*Note: It was possible to preserve yeast strains before this, but the process was tricky at best, relying mainly on spent yeast to create starter cultures for the next product. Of course, the term “starter culture” is an anachronism as it was not until the 1860s that Louis Pastuer discovered that yeast is indeed a living organism.