Barrel char levels impact on the taste of Whisky. The inside surfaces of new barrels are exposed to flames as part of the barrel-making process. This process creates a deeper burn char into the wood than the process of toasting. But how do they impact on the flavour of whisky?
This Charring affects the flavour and colour of the spirit aged in the barrel. Older barrels are sometimes rejuvenated and re-charred to prolong their useful life.
Charring the casks will impact on wood compounds, such as lignin, in different ways. This in turn will affect the flavour of the new make spirit deposited into the barrel, ahead of maturing for a few years and becoming a whisky in due course.
There are different levels of charring depending on how much time the barrel wood is exposed to flames. The whole process will impact on the flavour of the whisky which also benefits from the filtering out of unwanted sulphur compounds.
Loch Lomond Distillery is one of only a handful of Scotch whisky distilleries to have their own cooperage on site. Below is a video taken by a visitor to highlight the rejuvenation process of a cask for use again, including charring of the barrel.
There are some really interesting articles available online on the topic of barrel charring and the impact on whisky.
The Whiskey Wash website has an article on the differences between a charred barrel and a toasted barrel. Click here for the full article.
Another excellent article comes courtesy of Emily Bell at Vinepair. On this article, there is a good description of how the impact of char levels on a barrel affect the flavour of whisky and why. Click here for the article.