malting
Roasting
Take malt or raw grain to high temperature in a rotating drum to produce the deep colours and roast flavours of porter, stout and dark lager.
What is actually happening
Roasting runs well above kilning temperature, into the range where pyrolysis rather than Maillard chemistry dominates. The result is chocolate, coffee, char and — at the extreme — acrid bitterness.
Whether the grain was malted first matters more than the colour reached. Roasted barley is never malted, and carries a sharper, drier, more acrid character than chocolate or black malt at the same colour. That difference is most of what separates a dry stout from a porter.
Typical conditions
| Temperature | 180–230°C |
|---|---|
| Scale | A commercial-scale operation |
Ranges, not targets. These describe what is usual across the styles and breweries that use this step, and a value outside the range is a decision rather than an error.
Styles where this step is decisive
- Dry stout
Sharp roasted-barley bitterness over a light body and a very dry finish — much lighter to drink than its colour suggests.
- English porter
The original dark British beer: chocolate and light coffee over a nutty malt base, restrained rather than aggressive.
- Schwarzbier
Nearly black but remarkably light on the palate: smooth roast, clean lager finish and none of the heaviness the colour suggests.
- Irish extra stout
A stronger, fuller dry stout with more malt depth and body while keeping the sharp roasted-barley character.
- Sweet stout
A stout sweetened with lactose, giving chocolate and cream character over a full body and gentle roast.
- Oatmeal stout
A stout brewed with oats for a silky, full mouthfeel, balancing roast against smoothness rather than sweetness.
- American stout
A bold, hop-forward stout combining strong espresso roast with American citrus and pine hop character.
- Imperial stout
The strongest stout: dense, viscous and intensely roasted, with dark fruit, chocolate and substantial alcohol warmth.
- Foreign extra stout
A strong export stout, more intense in roast and body than a dry stout, historically brewed to travel.
- Tropical stout
A strong, sweet, fruity stout brewed for tropical markets, with less roast bite than its Irish relatives.
- Pastry stout
A heavily adjuncted sweet stout built to taste like dessert, using lactose, vanilla, cocoa and similar additions.
- American porter
A stronger, more assertive porter with deeper roast, firmer bitterness and often American hop character.
- Baltic porter
A strong dark lager descended from exported English porter: deep roast and dark fruit, remarkably smooth for its strength.
- Black IPA
An IPA with dark malt for colour and a light roast edge, keeping full citrus and pine hop character.
- Czech dark lager
A dark Bohemian lager richer and sweeter than its German counterparts, with caramel and light roast over a soft body.
- Munich Dunkel
Deep brown Bavarian lager led by rich Munich malt — bready and gently chocolatey, without real roast bitterness.
- Dark mild
A low-strength dark British ale, gently sweet and nutty, built for drinking in quantity after physical work.
- London brown ale
A low-strength, notably sweet dark brown ale from London, now largely extinct as a commercial style.
Related steps and concepts
- Kilning — The gentler equivalent for base malt.
- Roasted barley — The unmalted product.
- Black malt — The malted product at similar colour.
Also at the malting stage
See the whole process in order on how beer is made.
Last reviewed 2026-08-16.