Peat. What is Peat and how does it make whisky smoky?
Soapy, sulfuric, medicinal and seaweedy or smoky, rich, fruity and spicy can all be flavours imparted by this decomposed plant matter.
Peat is made from partially decomposed plant remains – grasses, mosses and heather which has been in a waterlogged environment and starved of oxygen.
The very top, soft layer is the Peat Moss you can find at your local hardware store for plants and such. The next level down is used as it contains a lot of roots and it’s these roots that provide most of the flavour, this section is usually 1,000 to 5,000 years old. The very bottom layer is about 10,000 years away from becoming coal!
The surrounding environment of a peat bed shapes the flavour of the peat and ultimately the whisky, such as the type of roots, grasses, moss etc
Peat, when burned, creates a group of chemical called Phenols. When the peat is burned during the kilning process, that smoke and other chemicals are absorbed into the barley. The more peat burned, the smokier the whisky. The amount of phenols is measured in Parts Per Million. Many Scottish Whiskies that are unpeated may have 1-4 PPM depending on where the water has been flowing.
- Lightly peated – below 15 PPM
- Moderately peated – around 20 PPM
- Heavily peated – above 30 PPM
At 20 PPM, that is 0.00002 % of the whisky. I find it absolutely fascinating that we can let alone taste that, but can tell the difference between these minute variations.
Peated Whiskies is mostly reserved for Scotch Whisky, and some other countries are using local Peat to make Single Malt Whiskies. Peat is definitely an acquired taste, something I have yet to fully acquire.
Canadian Whisky, for the most part, does not have any phenols in its chemical structure. But we have plenty of Peat in this big country and wouldn't be surprised if someone started putting it to good use.