Nikka Coffey Grain Whisky is a 100% Japanese Grain Whisky distilled in Coffey Stills. The Coffey Still is a type of continuous column still patented by French-born Irishman Aeneas Coffey in 1830. Nikka has two Coffey stills in their Miyagikyo distillery mainly for the production of grain whisky. Interestingly, Nikka are the only whisky distilling company to make a Malt Whisky in Coffey Still too (link below). These two old Coffey stills were imported from Scotland in 1963. The distillation process is continuous, whereas the pot stills which are used in single malt production require two separate distillations. These old stills produce a distillate with more flavour and depth than modern column stills, imparting a distinct character to Nikka’s blended whiskies. Nikka Coffey Grain Whisky is based on corn, as was traditionally the case – most modern grain whiskies rely on wheat.