Malt overview — base, specialty, and roast
How malt is categorised, what each category contributes, and how to read a malt spec sheet.
Last updated 2 April 2026 · 10 min read
The three groups
Most malts you’ll buy fall into one of three categories:
| Category | Diastatic power | Typical % of grist | Examples |
|---|---|---|---|
| Base malts | High (50–150 °Lintner) | 60–100% | Maris Otter, Pilsner, Pale Ale, Vienna, Munich |
| Crystal/caramel | Zero | 0–20% | Crystal 20, 40, 60, 90, 120 |
| Roast & specialty | Zero | 0–15% | Chocolate, Black Malt, Roast Barley, Special B |
Diastatic power is the malt’s ability to convert its own (and other) starches into fermentable sugar during the mash. Only well-modified base malts have meaningful enzymatic capacity. Crystal and roast malts contribute flavour, colour, and unfermentable sugars (for body) but no enzymes — they must be paired with a base malt that can convert the whole mash.
Reading a spec sheet
- Colour (°L or EBC): how dark the malt is. 1 °L ≈ 1.97 EBC.
- Moisture: below ~5%. Wet malt is bad malt.
- Diastatic power (°Lintner or WK): enzymatic capacity. Above 35 °L can convert itself and a roughly equal weight of adjuncts.
- Potential yield (ppg / extract %): sugar yield per pound per gallon (US) or as a percent of the kernel weight.
- Moisture, protein, FAN, free amino nitrogen: mostly relevant if you’re brewing high-gravity or all-malt European styles.
Substitution rules of thumb
- Base malts substitute well for one another within their region — Maris Otter ⇄ Golden Promise ⇄ Pearl. Pilsner ⇄ Pilsner from a different Continental maltster.
- Crystal malts of the same colour rating from different maltsters are interchangeable for practical purposes.
- Roast malts are NOT interchangeable. Chocolate malt and roast barley produce very different flavours despite similar colour.
Storing malt
Crushed malt loses freshness within weeks. Whole malt stored cool and dry will keep for 6-12 months. We sell uncrushed by default; ask at checkout for a crush.
Related products
- Maris Otter Pale MaltThe classic British base malt. Rich, biscuity wort with enough enzymatic power to convert itself and an adjunct or two alongside.
- Weyermann Pilsner MaltA very pale, well-modified Continental base malt. The starting point for almost every German and Czech lager, and a clean canvas for Belgian ales.
- Crystal 60 LMid-colour crystal malt. Adds amber colour, body, and toffee/dried-fruit sweetness without overpowering the base malt character.
- Chocolate MaltA roasted malt that delivers chocolate, espresso and dark-cocoa flavour. The defining colour and flavour grain of porters and brown ales.