How to Crush Your Own Malts at Home

Crush Your Own Malts at Home

Are you wondering how to crush your own malts at home? Learn more in this article.

When I got my first job at a small brewery, I looked forward to days spent developing recipes, tending to a gently rolling boil, and assessing the quality of the results.

What I did not picture was hours spent sitting on an upside-down 5-gallon bucket, with a drill in one hand and a bag of grain in the other, feeding malts into a hopper and running the drill until I crushed enough grain for multiple 15-gallon pilot batches. 

I also could not imagine spending more time cleaning than actually brewing, but that’s a story for another day. 

Of course, I would eventually get the chance to brew, but first, learning how to get the most out of the freshest ingredients was a foundational skill that has served me well over the years. Now, my homebrew benefits from greater consistency due to dialing in the crush of my malts.

Sure, I also save a few bucks by crushing grain at home versus having the homebrew shop handle that task, but the real advantage is in the freshness and efficiency of my brew.

Each homebrew system is unique. By taking matters into my own hands to fine-tune the crush of my malts, I get an improved yield over time. Like grinding my own coffee beans just before brewing a cup, crushing my own malts on brew day also leads to the freshest possible flavors in my beer.

Equipment Needed: 

  • Grain mill, hopper, and base
  • Handheld driver or drill
  • 6.5-gallon grain bucket
  • Scale

Alternatively, if you don’t have a mill, you can use a rolling pin to crush malt at home. Not to say it’s impossible, but the rolling pin method won’t be very efficient for a typical 5-gallon all-grain batch. However, if you are extract brewing and need to crush a small number of specialty malts for your brew, you can use this method.

Place your malts in a freezer bag, seal it, and use a rolling pin to roll back and forth on top of the bag firmly. Stop when the husks of your grain begin to crack open, and the kernels are crushed but not totally pulverized. 

For all-grain brewing, here are the steps you should take to crush your own malts at home:

Step 1: Weigh Your Grain

How to crush your own malts at home?
When planning to brew with grain, you’ll need to work backward from your targeted original gravity

Plan your malt quantities and use a scale to weigh out the grain bill for your batch of homebrew. When planning to brew with grain, you’ll need to work backward from your targeted original gravity to determine how much malt to use in your recipe. 

Step 2: Set Up Your Mill

I use a roller mill with a hopper mounted to a wooden base and placed over a five-gallon bucket. You can make your own base from the lid of your grain bucket, or a piece of wood, by cutting a hole that aligns with the bottom of the grain mill. Milling grain can be a dusty business, so a piece of cardboard can come in handy if there are gaps between your base and the container you are dropping your freshly milled grain into.

You can opt to use the hand-powered crank, but a hand drill will allow you to finish the task more quickly and with less effort. Install the driver on the crankshaft of your mill, and now you’re ready to crush.

Step 3: Calibrate The Crush Size

Malt requires crushing for the hot water in your mash to access the inner parts of the grain so that the enzymes can convert the starches inside the grain into fermentable sugars. The husk then serves as a filter to allow good flow during lautering. 

The rollers in my mill came calibrated to a default setting, which can be adjusted to achieve a finer or coarser crush as needed. Start by running a small amount of grain through your mill to ensure you have a good balance of cracked husks and crushed kernels. If the mill is not adjusted correctly, you may experience poor mash efficiency or long runoff time.

Step 4: Fill The Hopper With Grain And Begin To Crush

Once you have determined the appropriate crush size, fill the hopper with grain and start your drill at the lowest setting. Once the grain is moving through the hopper, you can gradually increase the speed of your drill. 

Step 5: Repeated Until The Entire Bill Is Crushed

Top off your hopper and continue crushing until you’ve made your way through the whole grain bill. A 6.5-gallon bucket holds around 15 pounds of milled grain. If you need more milled grain than that, have additional buckets nearby ready to go.

Step 6: Evaluate Your Crush

Too coarse a crush will make your sparge go too fast, and you’ll end up with low efficiency. Too fine of a crush can lead to a stuck sparge or hazy beer. Monitor your results and adjust accordingly. If you do end up with a bit of a fine, powdery crush, avoid making porridge in your mash tun by adding a handful of rice hulls to your mash.

Rice hulls are readily available at your local homebrew shop and are cheap to buy. They can act as filters to help the liquid flow through during your sparge without adding any undesired flavor or color to your beer. 

Step 7: Clean And Maintain Your Mill

You can take a few steps to make sure your mill stays in excellent condition between brew days. First, wipe away any dust, disassemble the hopper, and remove the plates surrounding the mill’s rollers. Next, use a brush to wipe the rollers clean. Then, apply a few drops of vegetable oil to resist rust and keep the mechanical parts lubricated. Finally, before using the mill for your next batch, you can wipe away any excess oil to avoid any unnecessary clumping of grains and to keep any oil out of your brew.