The Deanston distillery is located just a half an hour's drive north of Glasgow, Scotland (and not far from Edinburgh either), near the town of Stirling alongside the River Teith. It's just barely in the Highlands and has that honey-forward flavor I associate with the lower Highland area.
In addition to producing single malt scotch whiskies, Deanston is the "spiritual home" of the Scottish Leader blended scotch brand. The distillery is open to the public for tours.
The River Teith is the source not only of water for distillation, it is the power source of the distillery. River water flows into the distillery and passes through a hydro-electric station. They use only 25% of the power generated to supply the distillery (they say it is the only self-powered distillery in Scotland), and sell the rest of it back to the national power grid.
Previously the water powered a huge water wheel to accomplish the same thing. The distillery was originally built as a cotton mill. Here's a brief overview of the history:
- 1785 The Deanston Cotton Mill opened. The cotton mill employed and housed a whole town (the houses are still a few hundred yards away), printed their own currency, and offered schools and other services for the workers.
- 1965 The mill closed.
- 1967 The mill reopened as a distillery. The weaving shed became the barrel warehouse.
- 1974 The first Deanston single malt was released
- 1982 The distillery closed in the bad whisky economy that was about to turn around
- 1991 The distillery reopened in the good whisky economy from the 1980s
- 2000 Deanston received certification to produce organic whisky
- 2008 Deanston begins bottling only non-chill-filtered single-malts
Making Whisky at Deanston
For Deanston's single malts they use all un-peated barley (less than 2ppm phenol), and soft river water that flows over granite (so no peat in there either).
Their malt mill is a Porteus mill, which is so sturdy they've only had to recalibrate it twice since the 1960s. Unfortunately for the company they made their machines so well they went out of business as people didn't tend to need to buy new ones. The mill grinds the malted barley but does not separate out the husks.
They have a rare, huge open-top mash tun that holds 11 tons of barley/water though they do 9-ton mashes. Mashing is where the ground barley is washed with hot water to release sugars and leave behind the solids. As is typical, they wash the grains three times with different temperature waters:
- 64 Celsius water: Gets the enzymes out of the barley without destroying them, along with some sugars. (These enzymes will help break up the larger sugars so they can be fermented by yeast.) The sugary/enzyme water goes toward fermentation.
- 78 Celsius water: To remove the majority of the sugars. The sugary water goes toward fermentation.
- 88 Celsius water: To remove last bits of sugar. The sugary water goes into the next mash (the next batch) rather than into fermentation.
There are 8 washbacks, 60,000 liter steel (not stainless) tanks. Yeast is added to the sugary water for fermentation. Yeast comes in liquid form via tanker. Yeast is combined with the wort (sugar water) at about 19-20 degrees Celsius. During fermentation, the liquid naturally heats up then cools at the lend.
They do a long fermentation- 100 hours- that includes a secondary fermentation to bring in fruity, green-apple notes.
Distillation and Aging
Then it's time for distillation. At Deanston they have 4 stills - 2 wash stills (first distillation) and 2 spirit stills (second distillation).
The first distillation in a 15,000 liter still brings the fermented beer from 8% ABV up to 23-25%. They don't make any heads/tails cuts in the first distillation. The second distillation in a 14,000 liter still takes the spirit up to an average of 68% ABV.
The lyne arm/swan's neck of the still tilts slightly upwards at an angle, which also helps produce a lighter, fruitier style of Highland whisky.
During distillation, they manually adjust the stills to prevent over-foaming - the distiller looks into the windows of the stills and cuts down the temperature if it's foaming all over the place. They boil the spirit at a relatively low temperature to increase reflux/copper contact, which also helps produce a light spirit.
New make spirit goes into barrels at 63.5% ABV. The water used to reduce the spirit to barrel proof is river water that has been treated with a UV filter to ensure nothing grows in it. The barrels, 50,000 or so of them for their single-malts, are stored in the former weaving shed - a unique aging facility in Scotland.
This building has a ceiling (unfortunately difficult to photograph) similar to sherry bodegas with tall cathedral-style arches and central poles that collect water from the roof down through their middles. The high ceilings were to maintain consistent temperature year-round (better for the sewing equipment) and were covered with grass.
There is only a 5-6% temperature change in the warehouse during the year, which gives them less than a 2% evaporation rate (angels' share).
To bring the whiskies down to bottle strength, they use municipal water that has been demineralized on-site using a resin bed filtration system. They do not chill filter their whiskies, but they run them through a paper filter before bottling at room temp.
- 12 Year - The flagship product, with tastes of biscuit and ginger spice. All the whiskies have a honey note.
- Virgin Oak - No age statement whisky aged in ex-bourbon casks of various ages, then finished in virgin oak casks from Kentucky for 9-12 weeks. My host and brand ambassador for the Burn Stewart Distillers whiskies, Dr. Kirstie McCallum, calls the Virgin Oak a "summer whisky."
- Spanish Oak - Aged 10 years in ex-bourbon casks then 9 years in ex-Spanish brandy barrels, with dried fruits and nutty sherry notes.
- Sherry Cask - I think this was a limited edition, aged for 10 years in ex-Oloroso sherry barrels
- 1974 - Aged 37 years in ex-Oloroso sherry casks, yet it still comes in at 50.3% ABV (showing their super low angels' share). It has rancio, ashy, high vinegar notes of super old sherry.
My trip was hosted by the parent company, Burn Stewart Distillers, who also own Bunnahabhain, Tobermory, Ledaig, Scottish Leader, and Black Bottle. I also visited Bunnahabhain and will write about that more in another post.
By the way, Deanston was my 100th distillery visit!