The actual distillery itself is only one of four very important stages in the process of making single malt. Each of these has significant impact on the final taste of the whisky.
The malting
To be classed as single malt, a whisky must made entirely from barley. Blended whisky contains other grain like wheat.
To make alcohol you need sugar. Applying heat and moisture to barley fools the grains into germination, releasing sugar energy. Drying then stops the process. This is malting. Peaty character in whisky traditionally comes from when dried peat was burnt in Scotland to provide the malting process heat.
The brewery
Before making whisky, first make beer but without hops. The barley is cracked to give access to the sugar inside, then hot water is added. The sweetwort is then drained from the barley husks and yeast added.
The yeast eats the sugar and produces alcohol, together with esthers and congeners that add to the whisky’s final taste.
The distillery
The beer is placed in a copper kettle or ‘still’. As it’s boiled the first steam that rises is alcohol and this is what we keep to make whisky. The steam also bounces off the copper, removing some unwanted sulphury tastes from the whisky.
Most single malt is distilled twice in a copper-pot still. (Irish whisky is often distilled three times.)
The bond store
All of whisky’s colour and up to 60% of its taste comes from the barrel. In Australia whisky must spend at least 2 years in a barrel.
The oak barrel does three things, it adds flavor to the whisky, it improves some existing flavors and finally it reduces some of the harshness of the new spirit.