Grain Selection and Malting
1. Selection of the Main Ingredients
Irish whiskey is produced from barley, wheat and corn. The amounts used depend on the type of whiskey. Naturally the grain contains a lot of starch within its shell. This starch needs to be converted to sugar which is needed for the fermentation where yeast transforms sugar into alcohol. Most sugar can be extracted if barley is malted. If it is not malted or wheat or corn is used, the grain is cooked under pressure in order to cut the starch into sugar.
The best whiskeys are produced from malted barley. However it is also the most expensive and laborious. In the following we describe all types of Irish Whiskeys.
Interesting fact: The Irish whiskey production is so great that the whole country could never fulfill the industry's demand with its regionally grown grain. Therefore much is imported from the continent.
Water is very crucial for the whiskey production. It is needed in many steps of the production like steeping, mashing, cooling or reducing the whiskey to bottle strength. In former times most of the power used in the distilleries often came from waterwheels. Below is a picture of the waterwheel of the Old Midelton distillery.
Depending on the use the water can be taken from rivers or lakes. However the water quality in most rivers is not high enough for the whiskey production. Most of the distilleries thus take their water from water from local wells.
In order to produce Malt whiskey the barley has to be prepared differently then for Grain whiskey.
The Old Way
During the early ages and during the great rise of the Irish whiskey industry, the barley was collected during the harvest season and stored in the silos at the distillery. The barley then had to be steeped and transferred to the malting floors. In the picture below you can see how the Midelton distillery transported its barley to the malting floors at the higher levels.
The barley has to be steeped in water to start the natural germination. It was then spread out on malting floors by hand with various tools. During the next five days the grain had to be turned regularly to ensure a even growth and to guard the malt from attacks of the all present mould. After enzymes inside the grain have transformed the starch into sugar the germination process needs to be stopped. Therefore the grains are dried until only 4% moisture remains.
In the old times peat was the cheapest source to produce the necessary heat for drying. However it added a smoky flavour to the malt. Thus most whiskeys back then had a smoky aroma. You can see the heritage of the peating process at almost all the distilleries. The houses with the pagoda shaped roofs used to be the kilns with the drying grid.
3. The malting process today
After many improvements today's process differs from the traditional methods. The barley is malted in the big malting companies that produce more efficiently and supply both the whiskey and beer industry. The desired peat level can be specified exactly.
Here we see one of the trucks from the big malters unloading the malt into the silos at the Bushmills distillery in northern Ireland.