While water is not technically an ‘ingredient’ in the distillation process, it is crucial to it.
Some distillers claim the water they use to make their ‘wash’ – specifically, where it is sourced from – has an impact on the flavour and/or texture of their spirit, although there is question over how much influence it can truly exert.
In gin making, water is generally added to the still alongside neutral spirit and botanicals to aid the distillation process. It is also used to help bring a spirit to ‘bottling strength’ after it comes off the still. Prior to use for dilution, water must be purified to remove contaminants, and hardening substances such as calcium; common purification processes include water distillation and reverse osmosis.
As well as being a part of the spirit itself, water is also important as a tool in distilling (for example, as a coolant in your condenser, or to help regulate still temperature through steam jackets).
However, with water availability predicted to be impacted significantly by climate change, its use – particularly in often-wasteful cooling systems – is one of the distilling industry’s most pressing environmental concerns. Gin distillers including Wrecking Coast and Greensand Ridge in England have developed closed-loop systems to conserve the water they use for cooling, saving thousands of litres per distilling run, while the use of cold distillation techniques can also reduce water demand.