Whisky The Macallan 18 Year Old Triple Cask. The Macallan Triple Cask 18 Years Old forms part of our Triple Cask Matured range a series of single malt whiskies crafted in a triple cask combination of European and American sherry seasoned oak casks and American ex-bourbon oak casks. Exquisitely and expertly married together, this trinity of spirits produces an exotic single malt with orange, velvety cocoa and wood spice flavours.