Peat (Peat)

Partially decomposed plant material formed in peat bogs is used as fuel in drying malted barley in whisky production. During drying, smoke from the combustion of peat is introduced, and this smoke gives malt and the subsequent whisky a characteristic smoky profile. Smoke notes primarily originate from the phenols in the peat smoke; the most important compounds are guaiacol and creosol, as well as other phenols, which contribute to notes of smoke, tar and spicy elements. The intensity of the smoke notes depends on the origin of the peat, its composition and the conditions under which the drying takes place; therefore the profile ranges from mild to heavily smoky, particularly in whiskies from Islay. The origin of the peat, often peat from specific wetlands in Scotland and Ireland, affects the aroma through differences in impurities and phenolic compounds. The level of peating is often measured as the phenol content in malt (given in ppm); low levels yield mild smoke notes, higher levels yield a more pronounced smoky profile. Overall, peat-based smoke is one of the whisky world's best-known characteristics and is particularly prominent in Islay whiskies and other regions where peat plays a central role in the drying process.