Understanding Alpha & Beta EnzymesUpdated 6 months ago
A Deep Dive into a Step-Mash Example
For more control over enzyme activity and beer character, break your mash into stages:
Beta-Amylase Rest
144 °F (62 °C) for 30 min
Maximizes beta-amylase → lots of simple sugars → drier, higher-ABV beer.
Saccharification Rest
155 °F (68 °C) for 15 min
Both alpha- and beta-amylase active → balanced sugars → moderate body.
Alpha-Amylase Rest
162 °F (72 °C) for 20 min
Alpha-amylase dominant → longer-chain dextrins → fuller body and mouthfeel.
Mash-Out
172 °F (78 °C) for 5 min
Halts all enzyme activity → locks in sugar profile before lautering.
Single-Temperature Mash Shortcut
151 °F (66 °C) for 60 min
Blends both enzymes into one rest—ideal for most ales when you want simplicity.
How Mash Temperature Shapes Your Beer
| Mash Range | °F (°C) | Enzyme Focus | Result | Styles |
|---|---|---|---|---|
| Low | 147–151 °F (64–66 °C) | Beta-amylase dominant | Very fermentable → drier, lighter body, higher alcohol | Saison, Tripel, Blonde Ale |
| Intermediate | 151–158 °F (66–70 °C) | Both enzymes active | Balanced fermentability & body | IPAs, Pale Ales, European styles |
| High | 154–162 °F (68–72 °C) | Alpha-amylase dominant | More dextrins → fuller body, sweeter finish | Scotch Ale, Sweet Stout, Porter |
Step Mashing Benefits
Nuanced Flavor & Clarity: Ideal for lagers and complex beers.
Common Lager Profile:
Protein Rest: 122–131 °F (50–55 °C), 10–20 min – breaks down haze-causing proteins
Saccharification: 149–158 °F (65–70 °C), 20–30 min
Mash-Out: 167–172 °F (75–78 °C), 5–10 min
Choosing Your Mash Temperature
Beer Style: Lighter styles lean low, rich styles lean high.
Grain Profile: Specialty malts may need longer or multiple rests.
Yeast Strain: Some yeasts prefer certain sugar profiles.
Quick Start:
Not sure? Go with 151 °F (66 °C) for 60 min.
Want crisp & dry? Try 144–150 °F (62–65 °C).
Want full & rich? Try 154–162 °F (68–72 °C) or add a dedicated alpha rest.
With these guidelines, dial in your mash for exactly the body, sweetness, and alcohol level you aim for. Enjoy experimenting!