"It is a fact well known that the old-established Scotch houses, above all others, are enabled to give a higher class of whisky, by reason of their careful study of the science of blending, which they have now reduced to a fine art....The idea is, to produce a blend so perfect that it strikes the consumer as being one liquid, not many – i.e., having absolute unity, tasting as one whole."
This theory of blends is coincidentally the same for one of my other great loves - tiki drinks - that combining spirits in multiple styles will produce sets of flavors that are impossible to create by any one distillery on its own.
To a lesser degree, this principle is at work in every bottle of single malt that doesn't come from a single cask. Most single malts are combinations of many different casks, which are put together to create a consistent flavor profile from batch to batch. More variety can be created by aging malt whisky in different varieties of casks, but there will always be a delineated range of flavors that evolve from the same spirit being put into oak casks. Even distillers that produce multiple styles of spirit in-house, such as Springbank, Benriach, Benromach, Bunnahabhain, and Bladnoch (that's a lot of Bs, isn't it?) are ultimately still producing those spirits with the same equipment, which will create noticeable similarities between the different varieties.
The next level would be blend malts, which are mixtures of malt whiskies from two or more distilleries. This vastly increases the range of possible flavors as there are dozens of different malt distilleries in Scotland. Compass Box is one of the most lauded producers of blended malts in Scotland, producing expressions like Spice Tree and Peat Monster. Other producers include independent bottlers like Douglas Laing, Wemyss, and Duncan Taylor.
Finally, there are blended whiskies, which are mixtures of malt whisky and grain whisky, either from multiple distilleries or a single distillery (Ben Nevis and Lochside briefly produced both malt and grain whisky). The components of a single blend will often include malt whisky from a dozen or more different distilleries with grain whisky from several different distilleries (there are only a handful of grain distilleries in Scotland). This means that the blenders putting together each expression have an enormous range of whiskies to work with, which, as I noted above, makes it possible to create flavor profiles that would be impossible to produce with the products from a single distillery.
While the grain whisky component is usually thought of as a way to dilute and stretch more flavorful and expensive malt whisky, it does bring its own set of flavors. Unfortunately it's very difficult to get a sense of what grain whisky has to offer as there are so few expressions available (even fewer that are cask strength) in the US for reasonable prices (Haig Club doesn't count). Corn and wheat (the two most common grains used in grain whisky) have their own flavor profiles that are distinct both from each other and from malt whisky.
|John Walker & Sons - from Alfred Barnard|
Another place to start is with a blended whisky like Johnnie Walker Black Label or Compass Box Artist's Blend. These already contain a number of different malt and grain whiskies, but their flavor profiles can be shifted dramatically by the addition of a bit more malt whisky, especially if it's heavily flavored. Wish your Johnnie Black was a bit more peated? Pour in a touch of Ardbeg or Laphroaig. Wish Artist's Blend was more aggressively sherried? Add a bit of Glenfarclas or Macallan. Even a tiny splash of malt can pull the blend in a new direction. This is, coincidentally, a great way to stretch your expensive single malts. While the home blends won't be quite as robustly flavored as the single malts, you may be pleasantly surprised to find how flavorful the blends can be with a little doctoring.
From there you can move on to more complex blended malts. Again, it's good to start with something a little more neutral as your base - Clynelish is fantastic for this purpose, Arran is also a solid pick, and the multitude of Speyside distilleries exist largely because they form such a good base for blends. Bourbon cask malts are probably the best, as the vanilla and oak will help to give balance and backbone to the other components. Refill sherry would be next best, especially if it's on the lighter side. The two simplest axes to work with are cask type and peat - both can nicely inflect the base malt without overwhelming it as long as you are careful about how much you add. You can try layering multiple styles of the same influence, e.g. the more coastal notes of sherried Bunnahabhain with the cleaner character of a sherried Speysider or multiple styles of peat from different parts of the country. Alternatively, you can stack influences, putting sherry together with peat for an elegant but smokey profile. At this point you will start to notice how different whiskies fit with each other, either meshing to form a coherent whole or remaining distinct elements within the blend. There aren't hard and fast rules - much of this has to be learned through trial and error, though caution and a light hand can help to reduce the number of drams that have to be poured down the sink.
Finally, if you can get your hands on some grain whisky that you don't mind tinkering with, you can go all the way to making true blended whisky from scratch. One tricky element is that the grain whiskies that are bottled are sometimes less neutral than what gets used in commercial blends. Experiment carefully as they can strongly influence the flavor of the blends you make with them. With that said, I highly recommend the Signatory North British 16 Year bottled for Binny's as one of the few reasonably priced cask strength single grain whiskies available in the States right now. If you can, experiment with different types of grain whisky - most grain distilleries currently use wheat as their primary grain, but Invergordon still uses maize as its primary grain and older ones made before the 1980s are also more likely to be made from maize (a switch occurred at that point as locally grown wheat became more economically attractive than American maize). A typical commercial blend is likely to be 50-80% grain whisky, but you can also aim for something more like Compass Box's Great King Street New York Blend, which was only 20% grain whisky. As I've already noted, experimentation is going to be critical to finding out what kind of blends work best for you. Though one great place to start is the recipe offered by Alfred Barnard in his piece "The Art of Blending Scotch Whisky", which utilizes malt and grain whiskies from every region of the country.
Glenlivets would today be called Speyside whiskies - many distilleries in the area used to append -Glenlivet to their name before cease-and-desist orders were sent out by the owners of The Glenlivet. Between the Speyside, Lowland, and grain whiskies, this should give a fairly mellow and balanced whisky aided by the more characterful Islay and Campbeltown malts (though somewhat less if you stick with unpeated whiskies from Bruichladdich, Bunnahabhain, and Hazelburn). As noted in Barnard's text, using some sherried whiskies in the mix will also help to give the final product character and body.
While it's perfectly acceptable to simply pour different whiskies into a glass, give it a swirl, and taste the results, if you really want to understand what's going on measuring each component and letting the result marry for days or weeks will be critical. For making single drams, a 50 mL glass graduated cylinder is perfect along with 30, 50, and 60 mL sample bottles for storing the blends. Additionally, this will let you more precisely proof down blends that are made with cask or batch strength whiskies, as they may be more harmonious (or just taste different) in the 40-50% ABV range.
I'll leave you with some general things I've learned. They're limited by the particular bottles that I've had open while carrying out these experiments and I'm sure I'll find out more in time, but here they are:
•Some peated whiskies are more forgiving than others. Highland Park and Bowmore give you a bigger margin for error and are less likely to dominate a blend, whereas Laphroaig requires a very light touch as it can all too easily dominate a blend. Others like Ardbeg, Benriach, and Springbank will run somewhere more in the middle.
•Sherried whiskies will initially dominate a blend right after mixing, but integrate more thoroughly with time.
•Adding more of a bourbon cask malt can help to smooth over the cracks between disparate malts - slip more in if things don't seem to be coming together.
•Don't be afraid to try malts that seem at first blush like they would clash - sometimes things like Auchentoshan and Bowmore can go together surprisingly well.
•Be extra careful with batch and cask strength malts when adding them to lower proof malts or blends. The extra alcohol also means extra flavor, so a little bit will go a long way.
For further advice, you can turn to the K&L Wines Spirits Journal and the Master of Malt blog, both of which have talked about the process of making blends at home.