Scotland Distillery Tour – Scotch Whisky Production

If you’re considering a visit to Scotland, chances are you’re also planning a Scotch whisky distillery tour. Scotland is famous for its whisky. With over 143 malt and grain distilleries licensed to produce Scotch whisky [as of March 2023], Scotland has the greatest concentration of whisky production in the world.

In 2019, I relocated from Vancouver, Canada to Hawick, Scotland, to work as a Scotch whisky distiller at The Borders Distillery. I was responsible for operating the mash tuns, the stills, and conducting distillery tours. So let me take you on a virtual tour of the Scotch whisky making process at The Borders Distillery!

The Borders Distillery is a relatively new player in Scotch whisky distilling scene. It opened its doors to the public in March 2018, making it the first distillery in the Scottish Borders since 1837. Situated in Hawick, Scotland, it is located in the Lowland whisky region.

Milling Process

The production processes for our scotch, vodka, and gin begins with the delivery of barley from local farmers in the Scottish Borders. The distillery is situated in the middle of a town, so we cannot use the traditional system of pouring into a sunken pit due to pest control reasons. Instead, we store the barley in blow-in silos. Once the silos are filled, the conveyer moves the cereal to the back of the distillery to start the milling process.

We use an Allen Roddick mill to grind the malt to a specific ratio of 10% flour, 70% grist, and 20% husk. The mill receives 5 tonnes (5,000kg) of malt, which is then fed into the semi-lauter mashtun. The mashtun acts as the beating heart of any distillery or brewery. It is where the yield, and therefore productivity is determined.

Mashing Process

During the mashing process, hot water is mixed with the milled malt to form a consistent and even bed. This allows water to percolate easily and freely into the underback. A typical mash takes between four to six hours depending on the time of the year. The resulting sweet sugary liquid, known as wash, is drained and collected into a stainless steel washback (fermenter). We pitch 40kg of pinnacle yeast into 24,000 litres of wash and allow it to ferment for 72-84 hours. The fermentation duration depends on our production schedule. Our aim is to produce a base liquid that can be distilled into an aromatic fruit-forward sweet spirit.

We use stainless steel washbacks because they are more energy efficient and can be thoroughly cleaned. By comparison, wooden washbacks, cannot be fully cleaned due to the porous nature of wood. Wood pores can harbour microbes that cannot be effectively removed by cleaning agents.

Distillation

Once fermentation is complete, we evenly pump the wash into two 12,500 litre capacity wash stills. We raise the temperature of the wash stills to around 96°C to separate the alcohol from the rest of the liquid. The alcoholic vapours travel upwards, down the lyne arm, and enter the condensers. The cooling water running through the condensers cool the vapours back into liquid form. At this stage, the liquid is referred to as low wines, and typically have an alcohol by volume (abv) of 25-30% abv.

The low wines are subsequently pumped into two spirit stills, each with a capacity of 7,500 litres. These stills feature a bump or onion shape, which promote high levels of reflux and high levels of copper contact. Our goal is to collect around 2,000-2,100 litres of pure alcohol through these distillations.

Scotch, Vodka, & Gin

The spirit collected from the spirit stills is around 71%abv. If we want to make our Scotch Whisky, we will dilute the spirit to 63.5%abv by adding water. Old Bourbon basks will be filled with this “new make spirit.” Casks are then stored in a bonded warehouse for whisky maturation. However, if the new make spirit is not filled into a cask, it will undergoes further processing to make vodka or gin.

Introducing the Carter-Head Still

In the image above, we see our Carter-head still. The Carter-head still was designed by the Carter Brothers, who apprenticed under renowned Irishman, Aeaneas Coffey. Aeaneas Coffey was famous for designing the Coffey still. The Carter-head still is a hybrid of a pot and column still. A section of the column is encased in a water jacket and is packed with sacrificial copper rings. These copper rings, specifically designed for our still, allow maximum copper contact, resulting in an extremely clean tasting spirit.

During a distillation, the vapour will rise up the still and pass through a section containing four perforated baskets. To make our vodka, we will run the new make spirit through the Carter-head still twice. In the first distillation, the baskets on top will contain nothing. In the second distillation, the baskets will contain a considerable amount of activated charcoal. Activated charcoal is a volatile substance which allows us to strip off flavours from the spirit to produce a very clean vodka.

We don’t necessarily have to extract flavor in this section of the Carter-head still. Using the same process we can impart flavor by placing a selection of botanicals into the baskets. We add a mixture of our botanicals, with specific ratios, into our four baskets. The resulting distillation will produce a flavourful gin.

For a better look into The Borders Distillery production process, I encourage you to watch the video below.

Watch it on YouTube Below