What is Peated Whisky?
Peated whisky divides opinion more than almost anything else in the whisky world. Here's what peat actually is, where it comes from, and how to approach it.
In this guide
- The whisky people either love immediately or need time to understand
- What is peat, exactly?
- How is peatiness measured?
- What does peated whisky actually taste like?
- Why do some distilleries use peat and others don't?
- How to approach peated whisky for the first time
- Peated whiskies to explore on Whisky Diaries
The whisky people either love immediately or need time to understand
Peat is polarising. Some people take one sip of Laphroaig and feel like they've found the whisky they've been looking for their whole life. Others find it medicinal, aggressive, or simply baffling. Both reactions are completely valid.
What almost everyone agrees on is that peated whisky is unlike anything else.
What is peat, exactly?
Peat is decomposed organic matter, mostly plant material, that has accumulated over thousands of years in waterlogged ground. In Scotland, it forms thick layers beneath the surface of moorland, particularly on islands like Islay and in parts of the Highlands.
It burns slowly and produces a dense, aromatic smoke. That smoke is what flavours the whisky.
During malting, barley is dried in a kiln after it has germinated. Traditionally, the fuel for that kiln was whatever was locally available. In parts of Scotland, that was peat. The smoke from the burning peat penetrates the barley and leaves behind a set of compounds called phenols, which survive through distillation and maturation and end up in your glass.
How is peatiness measured?
The level of peat influence is measured in parts per million (PPM) of phenolic compounds in the malted barley. This gives you a rough guide to intensity:
0 to 5 PPM — unpeated or lightly peated. You won't notice it unless you're looking for it. Most Speyside whisky sits here.
5 to 20 PPM — a gentle smoke character. Present but not dominating. Highland Park and Bowmore are good examples.
20 to 40 PPM — noticeably peated. Smoke is a central part of the flavour. Talisker sits in this range.
40 PPM and above — heavily peated. Laphroaig, Ardbeg, and Octomore territory. Smoke is the point.
It's worth knowing that PPM measures the barley, not the final whisky. Some of the phenols are lost during distillation and maturation, so the number on the label isn't a precise guide to how the whisky will taste. It's an indication.
What does peated whisky actually taste like?
Smoke is the obvious answer, but that's too simple. Peated whiskies from Islay in particular have a complex set of characteristics that go well beyond bonfire smoke.
You might find: medicinal notes reminiscent of antiseptic or iodine, seaweed and brine, tar, ash, smoked fish, or something earthy and dark. Underneath all of that there's usually fruit, sweetness, and vanilla from the cask. The best peated whiskies balance these elements rather than letting smoke overwhelm everything else.
The peat character on Islay has a distinctly coastal quality, shaped by the island's geography and the seaweed-rich peat itself. Highland and Speyside peated whiskies, where they exist, tend to be drier and more heathery.
Why do some distilleries use peat and others don't?
It's partly tradition, partly geography, partly choice. Before modern transport made other fuels widely available, distilleries used what they had locally. Islay had peat in abundance. Most of Speyside had access to other fuels and developed a lighter, unpeated style.
Today it's a deliberate decision. Some distilleries have always been peated and built their identity around it. Others produce both peated and unpeated expressions. A few, like Bruichladdich, make some of the world's most heavily peated whisky (Octomore) alongside completely unpeated spirit (Classic Laddie). The peat is a tool, not a requirement.
How to approach peated whisky for the first time
Don't start with Laphroaig 10. Or rather, don't start there if you want to give yourself the best chance of appreciating what peated whisky can be. Starting with the most intense expression is like trying your first glass of wine by opening an old Barolo. It's a lot.
A better path:
Start lighter. Try Bowmore 12 or Highland Park 12. Both have smoke as a supporting character rather than the lead. You'll get a sense of how peat works alongside other flavours without being confronted with it.
Work up gradually. From there, Talisker 10 is a good step. It has real peat presence but also pepper, fruit, and sea salt to balance it. If you enjoy that, Laphroaig and Ardbeg will make sense in a way they might not have cold.
Give it more than one try. Peated whisky is an acquired taste for many people, and that's not a flaw. Your palate adjusts over time. A whisky that seemed like too much at first often reveals layers of complexity once you've spent time with it.
Peated whiskies to explore on Whisky Diaries
You can browse peated expressions and read community tasting notes on Whisky Diaries. Seeing what other people found in the glass, particularly in the nose and finish, can help you know what to look for before you take your first sip.