The Kiln

Laphroaig's Working Pagodas

The pagoda which tops off the kiln and allows it to vent has become the emblem of the malt whisky distillery, which is a little ironic since the number who operate their own maltings, and so their own kiln, has shrunk to half a dozen at most.

Kiln Exterior, Dallas Dhu Highland Park Furnace Peat and Coke Stocks

So if you want to see a kiln in operation, your best bet is at Bowmore, Laphroaig, Highland Park or Springbank. And if you want to get a really close view, you can do no better than at Dallas Dhu. This is no longer operational and is now instead open as a museum, allowing views of parts normally too hot or smoky to approach.

Working Pagoda, Highland Park

Highland Park's Furnace

The kiln takes as its starting point the still germinating green barley from the floor maltings of the distillery. This is fed up to a mesh floor in the upperpart of the kiln where it is laid in a blanket, heated by the furnace below and permeated by its smoke.

The kiln has three purposes. The first is to stop the germination of the barley at the optimum time by heating it. The second is to dry the green barley enough to allow it to be milled, to be broken down enough to promote the mashing process. And the third purpose, in some cases, is to add a peaty smokiness to the flavour of the malt, and the whisky that is eventually produced from it.

This last of these is much misunderstood. It is probable that in the days when every farm had an illegal still, most malted barley was smoked over the central peat fires often used for everyday heating. The result must have been a flavour far too extreme for modern tastes (and the tastes of many at the time). But when you lived in an atmosphere of peat smoke anyway, you probably didn't notice: especially if you drank your whisky, as all but the well-off did, fresh from the still.

Against this background it is hardly surprising that blended whisky came into vogue in the 1800s. This tempered the excesses of most malt whiskies of the period with blander and more predictable (and cheaper) grain whiskies. It took over a century for most people to rediscover that properly matured malt whisky was actually drinkable, many believe preferable, on its own.

These days the furnaces in distillery kilns are fuelled mostly by coke (or in some cases oil) with peat added to the fire, if at all, for measured periods designed to give the barley a specific degree of peatiness.

After about 40-60 hours in the kiln, the barley has become light and fragile and is known as grist. It is then moved to the milling area ("all grist to the mill") where it is broken down into a rough powder. Here we return to a process that takes place in most distilleries, for those who rely on industrial maltings for their malted barley usually undertake the milling of it themselves, before feeding it into the next stage of the process, the mash tun.