Barley, water and yeast are the only ingredient in Scotch (colourings aside) but few people whisky drinkers seem to know or care much about it. Bruichladdich whisky distillery among others feels very differently about this, as shown by their recent terroir experiment, and few are keen to admit that more and more is being produced not in Scotland but in England.
How much Malted Barley is used for Whisky Making?
The Scottish whisky industry presently consumes an incredible 800,000 tonnes of malting barley a year for whisky distillation and a further 100,000 tonnes for the production of beer, the combined figure is expected to grow by around 20% over the next five years as new distilleries are established, mothballed distilleries spring back to life and existing ones are expanded.
This level of demand means that distilleries are turning to English farmers for barley as they have at least currently exhausted the supply capacity of Scottish Farmers. The HGCA Recommended List 2015 notes that approximately one third of all UK barley production is now used for malting, brewing and distilling.
What Strains of Barley are used?
Whisky producers are looking for low nitrogen concentrate, most contracts currently specify absolute maximum 1.65% (10.3% protein) though some require levels as low as 1.55%, high starch barley with high germinative capacity as this leads to far higher alcohol levels. Beer producers by contrast generally favours higher nitrogen content which goes some way to explain the popularity of dual approval grains such as Concerto and Odyssey. The profitability of supplying these grains has resulted in a number of commercial plant breeding companies such as Limagrain UK or Syngenta offering a range of barley varietals or “cultivars”.
When a new varietal reaches the market these undergo DUS (Distinction, uniformity and stability) testing before being given a position on the HGCA national list. The HGCA list classifies barley as suitable for brewing, malting or feed (one varietal may be used for more than one purpose) and provides yield performance for both spring and winter along with a disease resistance overview.
The current spring 2015 list includes: RGT Planet, KWS Irina, Olympus, Sienna, Vault, Octavia, Odyssey, Propino, Quench, Moonshine, Concerto, Tipple, Belgravia and Optic. The most commonly used of these malting varieties presently are Concerto and Odyssey are expected to comprise the bulk of the spring harvest.
Currently the dominant varietal, Concerto barley is one of the only varietals currently approved for both the UK brewing and malt distilling markets has a market share of approximately 43%, while resistant to mildew but remains susceptible to rhynchosporium and brown rust.
Odyssey is bred from the Concerto varietal with a has an excellent untreated yield, 3%
demonstrating solid resistance to brackling, and extremely high resistance to mildew and Rhynchosporium.
What Difference Does the Barley Make
The most popular barley varietals for whisky making are an interplay of considerations based on market demand and of course the drive for profit, farmers want high yields with low pesticide costs whereas distillers are looking for barley with a high starch ratio, meaning more sugar to make alcohol, and a low enough nitrogen ratio to ensure best possible yeast performance.
Other considerations such as where the barley comes from is seemingly more flexible, while Scotch must be made, aged (for at least three years) and bottled in Scotland there is no requirement that the barley be grown in Scotland. While the bulk of barley is currently grown in Scotland, a growing proportion comes from English farmers. That said a number of distilleries such as Bruichladdich take great interest in the origin, soil, climate and terrain of their barley noting that factors such as altitude make a measurable difference to growing rates and yield.
Terroir or a sense of Place
On paper it seems obvious that the climate the barley grows in, the soil type and the starch to nitrogen ratio of the yield will influence the whisky. After all this sense of place has been ingrained in the wine industry for a long time, going at least part of the way to explaining the negative, even dismissive attitude to new world vineyards, though it is worth noting that terroir has never taken root in the world of brandy.
If you’re looking for a scientific rational behind terroir then you need to consider methylation of DNA, without getting buried in the science DNA methylation events change the exact expression of a varietal by locking some genes on and others off. The methylation process can be influenced by changes in soil, temperature, rainfall and the amount of sunlight a plant receives.
Does Terroir Apply to Whisky
As with wine the notion of terroir makes a lot of sense for beer producers, the bulk of the liquid draws its flavour from the ingredients, but the same is not necessarily true for distillates. For starters a large number of whiskies are smoked or peated, then the distillation process may take Scotch to an alcoholic strength of 94.8% (190 US proof) leaving only 5.2% of the liquid which is not pure alcohol and the taste is further influenced by the size and shape of the still, as well as when the head and tails are cut. On top of all this, while estimates vary the interaction of spirit and wood is widely considered to account for between 60% and 80% of a whiskies flavour. You could be forgiven for assuming that with all of this added to the mix terroir is not applicable and the barley is only there for the sugar, you’d be wrong though.
Does Barley Grain Impact Whisky Flavour?
In a word yes! Of course the taste of the grain in whisky is not as pronounced as the grape flavour in wine, regardless the flavour profile of whisky does change based on the type of grain and its properties. While the number of distilleries giving emphasis to their barley is comparatively low, on some level you can see that this is already understood by their use of small batch distillation for barley and continuous distillation for other grains. Were the alcohol essentially pure and tasteless distillers would use the continuous still, it can be run constantly, has no need to be changed and generally distills to a higher ABV. It also produces milder less flavoursome spirits. Similarly triple, or quadruple, distillation creates much lighter spirits than standard double distillation.
Pure Alcohol Has Flavour
Contrary to popular opinion pure alcohol does have flavour, albeit not one that we are able to taste due to the high ABV, which is drawn from the fruits or grains used to make it. Regardless pot still alcohol, it’s not legally whisky until it is aged 3 years, is generally only distilled to around 70% ABV. While this would still be virtually tasteless to us due to the high alcohol rate, the oils and secondary constituents left behind by the barley can be identified by adding water and allowing us to perceive the sweet, fruity malt flavours.
Peating & Smoking – put simply while the preferred method of drying out a whisky can and will change the flavour of the barley, they do not remove it. The wood although very important still only imparts a percentage, not the total of the flavour, those smoky phenolics, roasted nut and cereal-flavoured compounds do the rest, with a lot of help from the water, yeast and the distillery.
The properties of the barley used are incomparably important to the process, which may explain why distilleries such as Bruichladdich which emphasise this quality are able to achieve liquid gold status with No Age Statements.
If you’ve ever read the Bruichladdich news & library section (highly recommended reading) you’ll quickly realise that they treat the barley with the same care and attention that other distilleries do the aging process. What you may not know is that they also settle for much smaller harvests in their pursuit of quality, around one quarter of the distilleries barley needs are met on Islay itself, despite the fact that yields are generally no more than half what can be expected on the mainland. It’s organic varietals have been known to fail entirely from a malting perspective and the bere barley used in some expressions offers only half what modern varietals would. The results are not yet in from their ongoing terroir experiments but the length of the day, the climate, the soil ph and altitude influence more than just the sugar to nitrogen ratio, so don’t count out that little heart of gold so fast.