đĄ Think cask finishing is just about extra time in wood? Itâs actually a chemical transformation that rewrites a whiskyâs flavour.
As a chemist wanting to transition into distilling, Iâve been fascinated by how different cask types contribute unique flavour compounds to whisky. When a whisky moves from its original barrel to a finishing cask, entirely new chemical reactions take place.
đș Sherry Casks (Oloroso & PX) â Think rich toffee, dried fruit, and spice. Compounds like sotolon & furaneol drive those nutty and caramelised flavours.
đ· Port Casks â Ever noticed that deep red berry and plum note? Thatâs malvidin, while vinyl guaiacol adds a subtle spice.
đ Madeira Casks â These give whisky a luscious caramel and almond depth, thanks to 5-HMF & furfural.
đ„ Cognac Casks â Ethyl vanillate & phenethyl acetate bring refined vanilla, floral, and oaky spice complexity.
đ Marsala Casks â Expect roasted nuts, dried fruit, and oxidative sweetnessâdriven by furfural & sotolon.
đŽ Rum Casks â Love tropical whisky? Ethyl butyrate & acetoin drive molasses, pineapple-like esters, and a buttery mouthfeel.
đŹ Why does this happen? Each cask previously held wine or spirits, meaning their wood is infused with unique flavour compounds that interact with the whisky over time. Oxygen, acidity, and residual sugars change the whiskyâs chemistry, adding layers of depth.
đŹ Which cask finish excites you the most? Are you team đș sherry for bold spice, đ· port for rich fruit, or đŽ rum for tropical depth? Or do you have a go-to that always delivers? Drop your pick below!
đ Infographic attachedâcheck it out!