The congener of “soot” is parts of the “burnt” sub category as part of the “peaty” head category.
“Burnt” is a congener that is chemically linked to a lot of chemicals. For an overview one can look at this page on the “the goods cents company” website. This website does not have a “peaty” congener, but it does have one for “smoky”.
First some links to explain what soot is:
Soot, a mass of impure carbon particles, is the result of an incomplete combustion of a organic material (HydroCarbon). This can be best illustrated by a photo. In the photo below one can see a “complete” combustion of a gas to the left and an “incomplete combustion” to the right. The result of a complete combustion, next to heat from the flame, is CO2 and H2O, meaning Carbon Dioxide and Water.
An incomplete combustion results in other other components. One of those is Carbon, Soot. If you have ever seen the inside of a fire place you will see the blackening of the fire place. This is the result of the incomplete combustion of wood, resulting in soot.
There are two stages in the whisky production process where soot from an incomplete combustion could come into contact with the components that make the whisky or the whisky itself. The first stage is during the drying of the malted barley in a kiln. The second stage is when the whisky is in a charred cask for maturation.
The carbon on the inside of the cask is not part of this blog entry.
First there is the drying of the barley with the heat and smoke of a peat/coke fire. Coke as in NOT COLA!! lol
Please see how the process uses an incomplete combustion to keep the heat from being to high. To create smoke or Reek an incomplete process of combustion is needed.
The smoke contains tar, phenols, lots of other components but also soot. Some call this “Reek”.
As is mentioned in the video’s by Highland Park, the fire uses coke, coal, and peat to dry the malted barley. Both Coke, Coal and Peat produce soot when combusted in an incomplete way.
The process can also be seen in the video’s Ralfy did at Springbank Distillery. See the explanation given at about 7 minutes into the video.
So soot is one of the by-products from the combustion of fuels in the kilning of the barley. This was also true for the Tar and it is also true for the Ash.
If soot was pure carbon it would have no smell. The soot is part of the smoke. I have never smelled just the soot, because it is part of the smoke. If you want to smell soot you would have to stand behind an old Diesel Car or Truck and wait for it to drive away. Since the smell of the soot would be a combination of incomplete hydrocarbons there is no way to say that “soot” would always smell the same. It is depending on the level of incomplete combustion and the material being burned incompletely.
Soot as a descriptor is therefor not very specific. If we limit ourselves to the soot produced at the kilning we would still need to be standing next such a fire in order to recognize the smell. So if you really want to know “Soot”, go visit the Springbank, Highland Park or Kilchoman distilleries. They do there own kilning. Only then will you be able to smell “soot” as it was (probably) intended on the Flavour Wheel.