During the 18th century the potato became more common in Scandinavia. Initially, it was solely for eating, but when Countess Eva Ekeblad in Sweden managed to render flour and starch from potatoes in 1774, it was not long before the first drops of potato spirit appeared. The potato then swiftly took over the role of grain in producing spirits in Norway, not least because of the fact that from any given patch of ground one could produce four times more spirit from potatoes than from corn.
To ferment potatoes they must first be boiled so that the starch is dissolved. Then add malt, which contains enzymes that convert the starch to sugar. Gradually, the aromatic smell of boiled potatoes pervaded the Norwegian rural districts, and the early 19th century saw the demise of grain as the raw material for spirit production in Norway.
This is probably when the humble potato was first referred to as “the grape of Scandinavia".