The Athrú Pot Stills
Ollie Alcorn is our head distiller here at the Lough Gill Distillery.
Why Three Pot Stills?
Irish whiskey has traditionally been distilled three times, which is why we have three pot stills. Scotch, on the other hand, has traditionally been distilled only twice.
Alcohol that undergoes triple distillation is lighter in flavour while maintaining a higher strength of spirit, resulting in a cleaner, crisper taste.
The first pot still (called the wash still) holds 15,000 litres, the second pot still (called the feint still) is only 12,000 litres and the third (called the spirit still) is only 7,500.
The distillate from the third pot still ends up in the spirit receiver. Here, we cut back the spirit from 83% ABV down to 63.5% ABV before it is pumped into ex-Bourbon casks and moved to our warehouse for three years and one day. Only then can it be called whiskey!
How Did We Choose Our Pot Stills:
Our pot stills are made by Frilli, an Italian company based in Siena, and are 100% copper with a stainless-steel bottom and the liquid is heated externally by heat exchangers to help with consistency.
Back in November 2018 (before the world had turned upside down!) while the distillery was being constructed, Brian Raethorne (Commercial Director) Christopher Kitchin (Distillery project manager) and I made a trip to Siena, Italy to see our pot stills being fabricated and to make plans for the coming installation.
In these pictures, you can see the stainless steel still bases before the main body was welded to it. Our still bases are concave which allows the liquid inside to drain into the recirculation line easily under gravity.
Our stills are heated externally using a plate heat exchanger with steam to heat the plates from the opposite side. Steam generation is a vital part of whiskey production as it's the most efficient and clean way to distil alcohol.
How Does This Shape The Taste Of Our Whiskey?
The design and configuration of our pot stills is to maximise reflux, which will in turn give us a lighter and more refined spirit.
Reflux is when the ethanol vapour condenses before reaching the intended condenser, meaning it gets re-boiled more than once and has increased copper contact and therefore, better flavour.
The bulbs just above the still pot naturally have cooler pockets where some of the vapour will condense and drip back into the pot. The still necks are quite tall and lead into an ascending lyne arm on all 3 stills, which again, maximises the reflux of heavier congeners.
