The Still Room
For me the most impressive process in Whisky production is distillation. The big copper pot stills, used in the production of Single Malt Whisky, seem to be the most complex equipments at a distillery. Copper is important as it removes highly volatile compounds including sulphur from the distillate. Distillation is carried out in these beautiful vessels by batch distillation. You can find other kind of stills in the whisky business like Column Stills, where the process is a constant process of distillation without a need to stop and start between batches. The final distillate has a higher concentration of alcohol and that means that they have a higher output and are more economical than pot stills. But hey, being the richest man in the cemetery doesn’t matter to Hedley G. Wright, the great great great grand son of Archibald Mitchell, who founded Springbank Distillery in 1818.
If you’re interested in Scottish Distilleries I can recommend a nice map for your office or tasting room. It contains all distilleries, working, closed and even planned.
For each of the three spirit styles produced at Springbank – Hazelburn, Springbank and Longrow – wash distillation is carried out in the same fashion. The wash from the wash charger is filled into the Wash Still up to the level of the man door . After closing the man door and the air valve, the steam valves are opened and the oil fire lit. The wash still at Springbank is heated by direct fire and internal steam coils. There are just a few pot stills like this in the Scottish Whisky industry. The effect of direct fire is some burning unfermented sugars on the copper bottom of the still. This certain amount of caramelisation brings additional flavours to the new make. Like stirring in a cooking pot the rummager ensures that on the bottom of the still aren’t too much scorched sugars. The next picture shows the rummager inside the Wash Still. Here I want to thank Ian Rich from the Springbank staff who shot the picture for me because I forgot to do so 🙂
Once the Wash Still produces distillate the application of heat must be controlled in order that wash does not travel up the neck of the still and out through the condenser to the Spirit Safe. The distillate, known as Low Wines, flowing from the still is monitored through the spirit safe and collected in the Low Wines Receiver.
Distillation of wash is continued until the alcohol strength of the Low Wines has fallen to 1% abv. This is after an average time of six hours. The oil fire and flow of steam is then turned off and the air valve and man door are opened again. The remaining content, known as Pot Ale, is discharged by pump to the effluent tank situated at Glengyle Distillery.
Low Wines collected at the Low Wines Receiver have an average alcohol strength of 15 – 20% abv.
When the distillate comes off the stills it has to condense back to liquid. Traditionally this is done in a special tub where coils of copper pipes are submerged in cold water. This apparatus is called a Worm Tub and only a few distilleries still use this traditional way of cooling the alcohol vapour. At Springbank No 1 Low Wines Still is connected to a Worm Tub.
The flow of distillate coming from the two Low Wines Stills can be switched into two directions. The still men can do this with the Spirit Safe. You can see this in the picture titled “Spirit Safe”. The jars on the left and on the right are connected to the Feints Receiver. Only the middle jar is connected to the Spirit Receiver.
As mentioned before Springbank produces three different spirit styles:
Triple Distilled Lowland style with no peat influence
Two and a half distillation, lightly peated
Double distilled , heavily peated Islay Style Whisky
The peat influence is not affected by the kind of distillation. It depends on the kind of kilning. I have described this in a previous post about malting.
The triple distillation of Hazelburn started in 1997. In the late 1980s Frank McHardy worked for Bushmills in Ireland. When he came back to Springbank in 1996 he decided to create a light lowland style spirit with triple distillation at Springbank. Triple distillation is the main distilling type in Ireland. Another Scottish Whisky Distillery doing triple distillation is Auchentoshan in the Lowlands.
From the Low Wines Receiver the result of the Wash Distillation is charged to No 1 Low Wines Still at a strength of around 20% ABV. The distillate of step no 2 is than collected to the Feints Receiver at a strength of 20 – 25% to charge No 2 Low Wines Still. The Feints of the 3rd distillation go back to the Feints Receiver, which makes the ABV increase to 35 – 40%.
When the distillate’s alcohol strength goes down to 78% the middle cut begins and the spirit is collected into the spirit receiver. This is continued until the strength falls below 63%. The average strength of the collected spirit is 71 – 75% alcohol. The distillation cycle of No. 2 Low Wines Still for Hazelburn takes around 13 hours.
With every additional distillation the spirit becomes lighter because more and more heavier components are left in the still. Unfortunately some of these components are full of flavours and stay in the spent lees.
If you are interested in more details about Triple Distillation you can visit Whisky Science.
To get a short impression about the Hazelburn taste enjoy Frank McHardy tasting a 8 YO Hazelburn in the still room:
Double Distillation is the most common type of distillation found in Scotland. With Longrow Springbank has a heavily peated Single Malt in its range.
Low Wines from the wash distillation are collected together with the “Foreshots” of No 1 Low Wines Still. This is the reason for the higher ABV (25 – 30%) in the charge of No 1 Low Wines Still.
During the part of the distillation where the Foreshots are collected, the distillate contains high volatile components which are regarded as impurities. The time running foreshots varies from distillery to distillery and is generally 20 – 30 minutes. The still man sometimes adds water to the distillate in the spirit safe to reduce the ABV to 40 – 46%. Adding water to the distillate will create a milky liquid, which is the result of the reaction to long chain fatty acids and their esters. Once the distillate runs clear when water is added the collection of spirit begins. This procedure is is known as the water test or demisting test.
At this point the still men reduces the heating and slows down the flow of distillate to a minimum. The temperature of the collected distillate has to be kept below 20°C.
This is important to keep the desired flavours of all Spirit types produced at Springbank Distillery.
The average strength of the collected new make in the spirit vat is 68% ABV. No 2 Low Wines Still will not be used for Longrow distillation.
Tasting note of Frank McHardy for the Longrow 14 YO.
A very unique type of distillation is used for Springbank. Two and a half times distillation is not easy to understand. You may ask how they manage to do the half distillation. In my opinion the term “Two and a half” is not the correct description for the way they do it, but I don’t find a better one either.
I will try to explain how it works:
The first distillation is the Wash Distillation like described above. When there are sufficient Low Wines collected, some 6850 litres are pumped into No. 1 Low Wines Still. Then the second distillation starts and the total is collected as Feints in the Feints Receiver. When sufficient Low Wines and Feints are produced from these first two distillations a mixture containing 80% Feints and 20% of Low Wines is pumped to and distilled in No 2 Low Wines Still.
The middle cut of No 2 Low Wines Still is collected as Spirit with an alcohol strength of 76 – 60%. The Heads and Tails go back to the Feints Receiver. With a lot of Low Wines bypassing the No 1 Low Wines Still, we have the “Two and a Half Distillation“.
The spirit distillation of Springbank is extremely slow with Spirit collected at around 230 litres per hour.
You might ask why they do it like this for Springbank? Well, nobody honestly can answer this. Every new generation was introduced by their predecessor to this technique and no written documents about this exist. So, like with everything at Springbank, they will never change it.
The result is a very complex and unique Spirit and you won’t find a Whisky with a similar taste.
Frank tasting the perfect introduction to the Springbank range. The 10 YO – my everyday Malt 🙂
Springbank Distilling Equation
To produce Single Malt Whisky you just need 3 ingredients:
- Malt (Barley)
The following pictures shows the distilling equation for Springbank distillery.
There is so much to tell about distillation and within our week at Springbank Whisk School we learned a lot of stuff. If you’re interested to get deeper into this fascinating topic – or if you wanna run your own distillery, like my Japanese class mate Kohei, I highly can recommend a book written by Professor Inge Russell: [thirstylink linkid=”1756″ linktext=”” class=”thirstylink” title=”Whisky Production”]