Bourbon is an American whiskey which is made from malted grains, 51% corn. It is stored in charred oak casks with no use of any additives. The bourbon must be made entirely within the United States in order to be qualified as bourbon. There are two other types of bourbon – straight bourbon and blended bourbon. Straight bourbon is from one American state that must be aged for at least two years with no use of additives. Blended bourbon is a mix of bourbon and other spirits, but minimum 51% of straight bourbon has to be in it. It is slightly sweet in taste, sometimes a bit smoky. Its reddish colour is the result of its fermentation in charred oak casks.
There are rules for this whisky to be qualified as a Scotch whisky. Scotch whisky must be made from malted barley or grain, mixed with the spirit aged in oak casks of maximum 700 litres, for minimum three years. To be called a Scotch whiskey, it must be made in Scotland. Scotch whisky can be further categorized as single malt Scotch whisky, grain whisky and blended Scotch whisky. Single malt scotch is made in a single distillery using only malted barley, water and yeast. Grain whisky’s main ingredient is maize or wheat. A blended scotch is a mix of single malt whiskies and single grain whiskies.
Irish whiskey is made in Northern Ireland. Yeast-fermented grain mash or a mash of malted cereals are used in making of Irish whiskey. It has to be aged in wooden casks for a minimum of three years. Compared to Scotch, Irish whiskey has a smoother finish.
As the name clearly suggests, it is produced in Japan. Japanese whisky is made from double malted or peated barley. Like Irish whisky, this one is also aged in wooden casks. This whisky is often drier and smokier, unlike other whiskies. It comes as single malt or blends.
Primarily produced in North America, Rye whiskey is made from the mash of a minimum of 51% rye. It is aged in charred barrels for a minimum of two years. Rye is a type of grass, a member of the wheat family. This whiskey is slightly fruity and spicy in flavour, highly recommended for making whiskey cocktails.
Tennessee whiskey is made in the United States. The only difference between Tennessee and Bourbon is the method of filtering. Before fermentation in the casks, Tennessee is steeped in charcoal.