What is Peated Whisky?

Traditionally, peat was used as a fuel before modern alternatives were available. It was harvested as part of the annual farming cycle – cut in the spring when at its wettest and sodden with winter rain and snow melt, then piled up and dried over the summer months before being used for heating, cooking and the preservation of meat and fish during autumn and winter.

Peat is cut using a traditional tool called a ‘tairsgeir ‘- a long wooden handled tool with an angled blade on one end. It cuts the peat at right angles on two sides. When cut peat is dense and clay-like with a consistency and look of good chocolate brownie.

How Does Peat Get into Whisky?

Peat enters whisky making during the malting stage – the process of turning naturally occurring starch in the grain to sugar. Sugar is needed to produce alcohol and the ‘green malt’ needs to be killed otherwise the sugar will be used to create a new barley plant.

Peat smoke is the traditional way of achieving this. A peat fire is lit in a kiln below a mesh floor holding the ‘green malt’ and smoke rises through it. The smoke dries the barley, killing it off.

A compound called phenol permeates the husk and is carried through the entire production process – milling, mashing, fermentation, distillation, maturation, and bottling – until it lands in your whisky glass. This is what you smell and taste in a peated whisky.

The smokiness or peat level of a whisky is measured by the phenol level or PPM scale (Phenol Parts per Million). Distillers increase or decrease the levels in their whisky by simply burning peat in the kiln for longer or less time, or with less or more intensity.

Where is Peated Whisky Made?

Scotland is the largest producer of peated whisky with the island of Islay being at the forefront. Islay is famous for its smoky style of single malt and remains one of the last bastions of the peated genre. This is also true for many other outlying and remote regions and is a direct result of being the final locations in the UK to receive modern fuel alternatives.

Peated whiskies are produced in other countries such as India and Japan, although they use peat or peated barley imported from Scotland. Elsewhere several craft distillers are using local peat sources where they have them. Leading examples include Mackmyra in Sweden, Stauning in Denmark and Westland in Washington state, USA.

The Drive to Make Peat More Sustainable

Several concerns about the burning of peat and releasing of carbon have been raised recently, along with damage to sensitive peat bog environments during harvesting. With peat only regenerating itself at the rate of one millimetre per year, nothing of significance will grow back during our lifetimes.

This has led to distillers trying to operate in more sustainable ways. Some are now powdering down the peat rather than using traditional blocks – this creates more surface area and therefore more smoke from the same amount of peat.

Higher amounts of phenol are also released. Industrial maltings are also using closed ventilation systems to recycle the same smoke through several batches of malted barley.