People stand in line for hours for smoky barbecue in Austin. Securing a table for a perfectly seared steak at one of NYC’s many famed steakhouses is often impossible. And whisky drinkers, and distillers, in the U.S. are tapping into the trend. You don’t have to look further than the distilleries making American whiskey — or even vodka or gin — with smoked oak, mesquite, or hickory to know that there’s something to the intangible goodness of a smoky liquor. But Americans are just catching on to what’s been done for millennia across the Atlantic.
In Scotland, Scotch whisky has the smoky flavor we crave nailed to a science, one that’s been in the making for at least 500 years. And those who love Scotch know the term is nearly synonymous with peat, the secret ingredient to Scotch’s complex flavors: bonfire, floral, fruity, nutty. “The peat is critical to the flavor, the final flavor, of Highland Park and many whiskies,” says Gordon Motion, master whisky maker of Highland Park Distillery in the Orkney Islands.
What exactly is this mysterious ingredient?
Peat bogs cover huge swaths of Scotland, about 20 percent of the country. What may look like soil is actual natural material made from decomposed plants that’s been compressed into the ground for thousands of years. It’s essentially young coal: Because the plant matter never fully breaks down, the peat stores large amounts of carbon.
The importance of peat to whisky can’t be overstated — nor can the peat’s origins. In the Orkney Islands, where Highland Park Distillery is located, the peat is more than 9,000 years old. Because there’s nothing between the Orkney Islands and America but ocean, says Motion, there are very few trees on the islands. So peat from the Hobbister Moor is mostly made of low-growing shrubs and is rich in heather. “There’s very little woody material in [the peat],” he says. “And when you burn the peat in Orkney, you get a completely different, sort of floral smoky smell compared to peat that you dug up from the mainland Scotland or from over in Islay on the west coast, which gives you a more TCP, iodine character.”
How does peat get into Scotch?
To achieve an aromatic smokiness in a Scotch like Highland Park 12 Year Old, you begin with malting barley. It’s a true labor of love for Highland Park. To start, distillers steep barley in water for about six to seven hours, let it rest, and repeat. This kicks off the germination process. Then, the barley is spread over the malting floor, and Highland Park is one of the few distilleries in Scotland that still turns its malt by hand. Although, they won’t turn their malt for too long; the germination process eventually has to stop so the barley grains don’t sprout completely and are still able to be fermented.
Then the fun starts: It’s time to start the first stage of drying the barley with peat. At Highland Park, peat is cut in April, dried naturally over summer, and then burned in its ancient kilns, where its heathery aromatic smoke infuses the malting barley. “In the early stages during the drying process, you’re just driving off the moisture that’s on the surface of the barley bed,” Motion says. “So it’s not actually drying down very much. But it’s at that point that the smoke from the peat fire adheres to the barley grains. So, that’s the point that you get the real smoky character in the malt.” Moisture must be ideally 30 to 45 percent at Highland Park to fully absorb the “reek,” or the smoldering peat smoke.
Peat is among the deciding factors of shaping how a whisky will eventually taste.
The peat found in the Orkney Islands, and in Highland Park, is unlike what you’ll find in any other Scotch. “Pulling peat from different regions of Scotland gives you a completely different character to a unique spirit,” Motion says. “The peat that’s burnt is unique to Highland Park. We’re the only distillery that has access to that peat, so we’re the only ones with that distinctive aromatic character.”
And how peat is used in the production of Scotch also differentiates distillers like Highland Park from others. Few distillers in Scotland still hand-malt, and fewer use peat to dry the barley. Commercial malters, in order to be energy-efficient, dry barley with hot air. “In order to get that peat character, you maybe still have to make that decision that you dry over a peat fire to get that character in,” Motion says. “It’s part of the production process for one of the raw ingredients. You know, if you think of it as smoky bacon versus unsmoked bacon, it’s that sort of thing.” And honestly, who would ever choose an unsmoked bacon over a smoky bacon — or a boring whisky over a peated Scotch?