MODULE 09 · 9 MIN
Dilution, Cask Strength, Filtration and Colour
Water may be added before bottling to reach a target strength, never below the Scotch minimum of 40% ABV. “Cask strength” generally signals little or no reduction after maturation, but exact practice and batch strength should be read from the producer’s statement rather than assumed.
Chill filtration removes compounds that can create haze at low temperature or after adding water. Non-chill-filtered whisky may become cloudy without being defective. Plain caramel colouring may be used to adjust appearance, but it must not be used as evidence of age, cask quality or flavour intensity.
Key ideas
Scotch is bottled at 40% ABV or higher.
Cloudiness can be a harmless filtration effect.
Colour alone cannot prove age or quality.
Glossary
- Chill filtration
- Cooling and filtering whisky to reduce later haze.
- Cask strength
- Whisky presented close to the strength at which it left the cask.
Three-question self-check
Pause before moving on.
1. Can you explain: Scotch is bottled at 40% ABV or higher.
Scotch is bottled at 40% ABV or higher.
2. Can you connect: Cloudiness can be a harmless filtration effect.
Cloudiness can be a harmless filtration effect.
3. Can you define “Chill filtration” in your own words?
Colour alone cannot prove age or quality.
Sources & further reading
- SWA — Scotch Whisky FAQsScotch Whisky Association
- SWA — Protecting Scotch WhiskyScotch Whisky Association
- The Scotch Whisky Regulations 2009UK Legislation
Last reviewed: 2026-08-09