Crushed vs Whole Malt: Do You Need a Malt Mill?

If you're brewing all-grain, your malt has to be crushed before it goes in the mash. The question is whether to buy it ready-crushed or buy it whole and mill it yourself. Here's how they compare, and how to decide whether a malt mill is worth it for you.

Why Malt Needs Crushing

The sugars you need are locked inside each grain as starch. Crushing cracks the husk and breaks the kernel into pieces so hot water can reach the starch during the mash. Uncrushed malt barely converts at all.

A good crush cracks every kernel into a few pieces while keeping the husks mostly intact. The husks form a natural filter bed, helping the wort drain clearly. Crush too fine, to flour, and the mash can become sticky and slow to drain; too coarse and you'll get less sugar out.

Crushed Malt: Pros and Cons

Pros

• Ready to brew: no mill, no extra time, no dust on brew day
• A consistent crush that suits most home brewing setups
• No upfront equipment cost

Cons

• Shorter shelf life. Once the grain is cracked, it's exposed to air and moisture, so it gradually goes stale. As a rough guide, use it within a few months, stored airtight.
• Less control over how fine or coarse the crush is

Whole Malt: Pros and Cons

Pros

• Keeps much longer. The intact husk protects the grain, so whole malt stored cool and dry stays fresh far longer than crushed.
• Fresher flavour when crushed just before brewing
• Full control of the crush to suit your system

Cons

• You need a mill, which is a significant upfront cost
• Extra time and a bit of dust on brew day

Which Should You Choose?

Buy crushed malt if…

• You brew regularly and will use your malt within a few months
• You're new to all-grain, or brewing small batches on your hob
• You'd rather spend your budget on ingredients than equipment

That's most home brewers, which is why we supply our malts ready crushed: speciality malts from 500g, and 25kg crushed base malts including Maris Otter, Golden Promise, lager and pilsner malt from Thomas Fawcett and Crisp.

Buy whole malt and a mill if…

• You buy in bulk but brew only occasionally, so crushed malt would go stale
• You want to fine-tune your crush for maximum efficiency
• You want the freshest possible grain on brew day

Choosing a Malt Mill

The Grainfather Electric Grain Mill + Mounting Board is a motorised roller mill for home brewers. It has 58mm fluted stainless steel rollers that crack the husk lengthways, 10 gap settings from 0.8mm to 2mm, a 1kg hopper, variable speed, and crushes up to 1.7kg a minute. The bamboo board sits over a bucket or fermenter so the crushed grain drops straight in. Also available as the mill on its own.

Setting the gap: start in the middle of the range and adjust. Brew-in-a-bag brewers can go finer, as the bag does the filtering. Systems that drain through a grain bed, like a Grainfather or a traditional mash tun, need a slightly coarser crush to avoid a stuck mash.

Only need a little? Small amounts of uncrushed malt, like our peated malt, can be crushed in a sturdy bag with a rolling pin. It's slow and uneven for a full batch, but fine for a few hundred grams.

How to Store Malt

• Airtight: reseal bags or decant into a sealed food-grade bin, especially 25kg sacks
• Cool and dry: away from heat, damp and sunlight
• Away from pests: mice and weevils love malt

Signs malt has gone stale: it tastes soft or chewy rather than crisp, smells musty or cardboard-like, or your brews start giving lower gravities than expected. Chew a few grains: fresh malt is crunchy and sweet.

Frequently Asked Questions

Should I buy crushed or whole malt?

Crushed if you'll use it within a few months, which suits most home brewers. Whole malt and a mill if you buy in bulk and brew occasionally, or want full control of the crush.

How long does crushed malt last?

As a rough guide, a few months when stored airtight, cool and dry. Whole malt keeps much longer.

Do I need a grain mill for all-grain brewing?

No. Buying ready-crushed malt works perfectly well. A mill is a worthwhile upgrade if you buy whole grain in bulk.

What gap should I set my malt mill to?

Start mid-range and adjust. Finer suits brew in a bag; slightly coarser suits systems that drain through a grain bed, like the Grainfather.

Can I crush malt without a mill?

For small amounts, yes: use a rolling pin on grain in a sturdy bag. For full batches, a mill gives a far more consistent crush.