MODULE 05 · 8 MIN
Water and Yeast: Function versus Myth
Water is used in mashing, cooling and dilution. Its chemistry can affect process efficiency and consistency, while reliable supply historically influenced distillery locations. Romantic claims that a stream alone creates a whisky’s flavour should be treated cautiously.
Yeast converts fermentable sugars into alcohol, carbon dioxide and flavour-active compounds. Strain choice, pitching rate, temperature and fermentation time can shift fruity, floral, cereal or heavier notes. Yeast is therefore both an engine of alcohol production and a contributor to new-make character.
Key ideas
Water supports several production stages.
Water-source stories should not replace process evidence.
Yeast creates alcohol and flavour precursors.
Glossary
- Yeast strain
- A selected type of yeast with particular fermentation behaviour.
- Flavour precursor
- A compound that can become or help form a later aroma or flavour.
Three-question self-check
Pause before moving on.
1. Can you explain: Water supports several production stages.
Water supports several production stages.
2. Can you connect: Water-source stories should not replace process evidence.
Water-source stories should not replace process evidence.
3. Can you define “Yeast strain” in your own words?
Yeast creates alcohol and flavour precursors.
Sources & further reading
- SWA — How Scotch Whisky is madeScotch Whisky Association
Last reviewed: 2026-08-09