The grist moves by a conveyor belt system into a Lauter Tun. Ours is made by Briggs and holds 2.6 tons of grain. It has a false bottom with slits to allow liquid through, but not solids. Hot water is added to the grist via the mash mixer. The ratio of grist to water is approximately 1:4 so that a hot mush like porridge is created. During the mashing process, heat from the hot water washes out the fermentable sugars, with the mash being constantly stirred using special hydraulic arms and rakes. Gravity causes the hot sugary water, known as wort, to seep down through the mash, out the false bottom, where it is recirculated back into the mash. The mash starts to behave like a sand filter and a turbidity instrument measures clarity of the wort. At the right clarity, the wort is drawn off and goes on to the next stage of the process, fermentation. The grist and water are mixed in the lauter tun three times in a process lasting around 6 hours. Each time the mash is mixed up and the temperature is increased (to around 60-70°C for the first wash, 70°C for the second and 80-90°C for the third) as a way to maximise the sugar yield. In the last wash, the sugar content of the wort is the lowest, so it is stored in the weak wort tank and used to prime the next batch in the lauter tun. The leftover mash is now called draff and is sold for animal feed. Water is very crucial for the whiskey production, as it is needed in many steps of the production including mashing, cooling and reducing the whiskey in strength. Ours is drawn from our own 120m well located beside the distillery and is passed through a filtration system supplied by Aquachem to maintain purity and consistency.