In October 2015, Georgie Bell, then global brand ambassador for Mortlach single malt Scotch whiskies visited Sydney to launch Mortlach Rare Old. At the conclusion of the formalities, we asked Georgie to explain Mortlach’s 2.81 distillation process.
Mortlach 2.81 Distillation Process – Photo © Cocktails & Bars
Mortlach Distillery
Mortlach distillery was founded in 1823 and lays claim to being the first legal distillery in Dufftown, Speyside. Dubbed as the “beast of Dufftown” by Dave Broom, Mortlach is said to defy what Speyside whiskies are known for, which is a spirit often referred to as being thick, rich, muscular, meaty, umami-led and savoury. This singular character is the result of a 2.81 distillation process in which the liquid is distilled 2.81 times. This process was started in 1896 by the distiller’s son, Dr Alexander Cowie and is still in use at the distillery to this day.
Mortlach 2.81 Distillation Process Explained
The 2.81 distillation process harks back to 1896 when it was invented by Alexander Cowie. He was working with Charles Doig at the time, the man who invented the Doig Ventilator, a pagoda rooftop which is a kiln chimney that attracts air from all directions, a process that changed the way Mortlach and other distilleries malted their barley.
For the 2.81 distillation, every part of the production process is tailored and calibrated to create Mortlach’s robust, savoury and muscular style. From the short fermentation (53 to 58 hours) through to the still house and the condensers, Mortlach uses worm tub condensers which are only found in fourteen distilleries across Scotland.
Mortlach distillery has 6 stills, 3 wash stills and 3 spirit stills and what sets them apart is that all of the stills are different in shape and size and they all work pretty much independently from one another. They don’t work in perfect pairs but create three different spirit characters from the three spirit stills which are then blended to create the house style.
“It’s like having three distilleries at the one still house”, Georgie Bell says.
The first of these is the pairing of wash still #3 and spirit still #3 to create a malty distillate. Wash stills 1 and 2 work as a pair, which is unusual. All the runs are split into halves, the heads and the tails. The first half from wash stills 1 and 2 are the low wines and the lighter half. These are run through spirit still #2 which creates a lighter floral distillate.
The heavier half of wash stills #1 and #2 is run that through spirit still #2 once but no cuts are taken. Everything that has been through the stills is run through a second time but with the tails from wash stills #1 and #2. The richer half and the heavier half get even richer and more viscous.
“If spirit still #1 is small and its filled high, then it’s a bit of a copper contact. So taking it around twice is not really cleaning it to that same effect, so no cuts are taken. Everything that has gone around that second time is run through a third time with the set of heads from wash stills #1 and #2 because by this point, it has become way too thick and way too viscous. A spirit cut is taken from that.”
A spirit cut is then taken from spirit still #1 from every third run. Mortlach use worm tub condensers and the water is cold at 10 degrees, which means as soon as that vapour hits the copper, it turns back into liquid. So when the spirit is in liquid form, the copper cannot do its work, so every part of the production process is calibrated to create this character, and this has been calculated to be 2.81.
“I know it is nearer to three than to two,” Georgie Bell adds. “Usually when you say triple distilled, you think of a lighter spirit. The 2.81 actually stands for the precision in the way that it has been distilled.”
“Mortlach 2.81 Distillation Process Explained” is part of the ‘Looking Back’ series and is based on an article originally published on our sister website Gourmantic in 2015.
