Glossary
Mash temperature
The temperature the mash is held at, which determines how much of the extracted starch becomes fermentable sugar and how much remains as unfermentable dextrin.
Also called saccharification rest, mash rest.
This is the single most useful thing a brewer can change to alter a beer’s body without altering its recipe. Two beers from identical grain, one mashed at 63 °C and one at 70 °C, will differ noticeably in dryness, mouthfeel and final gravity.
It is why "attenuation" is not purely a property of the yeast: a strain cannot ferment sugar that was never made.
Related
- Mash — The step this controls.
- Attenuation — What it largely determines.
- Dextrin — What a hot mash produces more of.
More vocabulary
Arrested fermentation · Barrel ageing · Batch sparging · Biotransformation · Blending · Bottle conditioning · Bottom fermentation · Burtonisation · Cask conditioning · Centrifugation
See every term on the glossary index.
Last reviewed 2026-08-16.