Single barrel spirits offer the world's rarest drinking experience

'Extremely rare' is a beguiling term to put on a bottle of booze. But there it is, emblazoned in gold on the curvy, voluptuous bottle of Glenmorangie 18-year-old that I place in front of a friendly chap who's ordered a dram.

It's his last day off before saddling up for 2016 and all he wants is a special drink to steel himself for the year ahead. But he has one question: "You've gotta tell me, though, is it actually rare?"

Every second person who orders this whisky asks me that question. Of course, it's no secret that in the world of aged spirits rarity sells. From the average punter to the polished aficionado, we all want to feel a bit privileged and special and experience something we can brag ... I mean appreciate the unique complexity of.

The whisky itself is outstandingly delicious, but come on, 'extremely rare'? Red diamonds are rare, a corpse flower in bloom is rare, pre-phylloxera cognac is rare, an honest politician – that's pretty rare. But a bottle of single malt whisky blended together from hundreds of casks with thousands of bottles available all over the world?

Being single

To answer the question I often pull out a single cask bottling of Glenmorangie from an independent bottler like the Scotch Malt Whisky Society (the society was sold to private investors by the Glenmorangie Company last year). The whisky in that bottle comes from one cask, and the label will tell you all sorts of handy info. Like how old the spirit is, what type of cask it was matured in, and crucially, exactly how many bottles of whisky were removed from that cask.

Just when you think you're familiar with the way a particular distillate should taste, whack, something comes along and changes everything you thought you knew.

You could argue that such limited expressions represent the pinnacle of rarity, but also, transience. Every cask of spirit is different, and once the couple hundred bottles from that barrel are gone, that's it, they can't be replaced. That precise combination of flavours will never exist again.

Yes, at times we get too obsessed with single origin, single cask, single vineyard, single farm, single milk cow products, forgetting how important the blender's art is to the most delicious drinks we sip. And no, I don't believe single cask booze is better than blended booze; they both offer different advantages.

What is, however, enthralling about great single cask spirits, though – be they whisky, rum, brandy, even tequila – is that they've achieved a rare and exceptional balance all on their own.

As no two barrels are the same, producers blend them together to achieve a consistent product that consumers can trust. Take blending out of the equation and you're left with a fascinating window into the dynamic nature of aged spirits.


In pursuit of inconsistency

Even though we're led to believe a brand of liquor has always tasted the same, that's not the case. Base grains and grapes change, fermentation and distillation methods change, the availability of certain types of casks changes. All of these changes are amplified when tasted through the lens of a single cask from different periods in a distillery's life.

And that's not even taking maturation into account, where different casks can completely transform a distillate beyond all recognition.

I've tried hundreds of different single cask expressions from Scottish, American, Japanese, Carribean, French and Australian distilleries. Just when you think you're familiar with the way a particular distillate should taste, whack, something comes along and changes everything you thought you knew.

Two single cask expressions I recently tasted reminded of this: a normally delicate and fruity Speyside malt that had turned into a big, spicy, funky behemoth, and a mostly fresh, refined Armagnac that had morphed into a rich, caramel, rancio monster.


Back home, our burgeoning Australian spirits industry is uniquely wedded to the single cask philosophy. The majority of Australian single malt whisky expressions on the market come from single casks, which is just one of the reasons why many old-world experts are enamoured with Aussie drops (whether or not this can be sustained into the future is a question for another day).This single-minded approach even extends to some of the fantastic rums we produce.

Last week I revisited Black Gate Rum from the eponymous distillery in Mendooran, central west New South Wales. It's quite distinct from most Caribbean rums, being matured in small sherry casks from the SA Cooperage in South Australia. On top of that, every bottling that distiller Brian Hollingworth has released is from a single cask.  

While some brilliant 'single barrel' Caribbean rums are available, most are either 'single distillates' or have been blended from a variety of casks and then finished in a single barrel, such as the Cruzan Single Barrel, Angostura Single Barrel, El Dorado Single Barrel, etc.

Not so with Black Gate Rum. Every bottling lists the cask number it came from along with the date it was bottled. Of course, you take a risk by only bottling single casks – variance is unavoidable. But having tried a few of these hard-to-come-by bottlings, I can happily report that each one has been as good as the last.

In some casks, the leathery, smoky, burnt toffee character so prominent in many Black Gate expressions is palpable. In other casks, the honey, caramel and fruit cake notes from the sherry really shine. The only problem: production is minimal, and because Hollingworth's stock isn't blended together to achieve greater volumes through batches, his rum can be difficult to find, rare even.

But it doesn't even say that on the bottle?

A professional barman in one of Australia's most revered whisky establishments, Luke McCarthy has also travelled the world to learn more about the spirits he serves. The result is two parts drinks culture and one part global trends, served with a dash of critical assessment.

What are the rarest spirits you've ever tried? Tell us in the comments section below.