Mash at 148-152°F (64-67°C) for a drier, more attenuated beer, or 154-158°F (68-70°C) for a fuller-bodied, sweeter one. 152°F (67°C) is a common balanced default. The difference comes from which starch-converting enzyme is more active at a given temperature — not from the grain bill or yeast strain.
Why mash temperature changes fermentability
Mashing converts starch into sugar using two enzymes with different temperature preferences:
- Beta-amylase — most active around 131-150°F (55-65°C), produces mostly fully fermentable simple sugars (maltose)
- Alpha-amylase — most active around 154-162°F (68-72°C), produces a mix that includes unfermentable dextrins alongside fermentable sugar
Both enzymes work across a wide overlapping range, but a mash held toward the low end lets beta-amylase dominate before heat denatures it; a mash held toward the high end favors alpha-amylase and shortens beta-amylase's active window.
What temperature gives a drier beer?
Mashing at 148-152°F (64-67°C) favors beta-amylase, producing wort with a higher proportion of fermentable sugar. Yeast consumes more of that sugar during fermentation, leaving a lower final gravity, thinner body, and — at a given original gravity — a slightly higher ABV than a higher-temperature mash of the same grain bill would produce.
What temperature gives a fuller beer?
Mashing at 154-158°F (68-70°C) favors alpha-amylase, leaving more unfermentable dextrins in the wort. Those dextrins pass through fermentation unchanged, adding body, mouthfeel, and residual sweetness to the finished beer without adding fermentable extract.
| Mash temp | Effect | Good for |
|---|---|---|
| 148-150°F (64-66°C) | Very fermentable, thin body, driest finish | Light lagers, dry saisons |
| 152°F (67°C) | Balanced fermentability and body | Most ale styles, general-purpose default |
| 154-156°F (68-69°C) | Fuller body, moderate sweetness | English bitters, brown ales |
| 157-158°F (69-70°C) | Fullest body, most residual sweetness | Milk stouts, barleywines |
A 60-minute mash is the standard recommendation for full conversion at any temperature in this range — cutting the mash short risks leaving unconverted starch behind, regardless of which body/fermentability profile you're aiming for.
Mash temperature and yeast attenuation both affect final gravity, but they're separate levers. A highly attenuative yeast strain mashed high will still finish fuller-bodied than the same yeast mashed low — the dextrins from a high mash simply aren't available for the yeast to consume, no matter how efficient the strain is.
Build your recipe around the right mash
Pick a BJCP style in the recipe calculator and get a full grain bill, target mash temperature, and complete brew-day plan for your batch size.
For the full mashing chapter — including enzyme chemistry, step mashing, and troubleshooting a stuck conversion — see Home Brewing Science.
Enzyme temperature ranges above are typical figures for standard malted barley — specialty malts, adjuncts, and non-barley grains can shift optimal mash behavior. Use a calibrated thermometer and stir well to avoid temperature stratification within the mash tun.