

Bourbon has to be aged in “virgin oak” i.e. a brand new barrel to be classified as bourbon. Which is why it’s so dark in colour and part of why it’s so sweet. They sell the used barrels off after they’re done with them to get some money back on the now unusable (for them) barrel.
Most Scotch is aged in ex bourbon barrels or ex sherry/port barrels. Using ex bourbon barrels gives the Scotch a lighter, more golden colour, and a more delicate flavour. Notes like vanilla, honey, caramel or florals.
Ex sherry and port give Scotch a darker amber to a deep red colour with rich and sweet flavours like stewed fruits, spices like cinnamon or cloves and a stronger darker caramel.
Most Scotch brand product lines will be like “ex bourbon barrel aged with: no age listed, 12 year old, 15 year old, 21 year old etc”. and then their other line will be the same again but in sherry barrels. They may also have a “sherry finish” where it’s aged for 10 years in bourbon then 2 in sherry, since the barrels impart less flavour the more they are used they can squeeze more out of the sherry barrels.
Sherry barrels cost magnitudes more than bourbon barrels. I was told (like ten years ago so grain of salt on the figures) that bourbon barrels are around 50-100usd per barrel while sherry is close to £1000 per barrel. Hence why the tariffs would be screwing over the industry.
/Rant
Source: I was a whisky bar manager that hosted a ton of whisky events/tastings for a few years.


The whisky industry is like multi billions worldwide, it’s not a small industry. There’s definitely some lobbying going on here lol.