The character and flavor profile of a finished brew is due to the presence of malted barley. The physical condition of the grains needs to be just right to achieve the desired yield efficiencies, and an appropriately adjusted mill will give us that condition.
Contents
The Best Crush
The brewer wants to open up the malted barley kernel to allow efficient process and extraction of all they need from the inside to create an excellent beer.
The husk needs to be split along the length and in big pieces. Starch and enzymes contained within the kernel need to exposed, to do so requires the crush to create several larger pieces and some smaller pieces. The brewer wants the least amount of flour that is possible.
To get the best crush for the equipment being used, the brewer must achieve a balance between a light crush and a heavy crush.
Light Crush – If the particles are large, then the husk is well preserved and will create a good filter bed. However, the barley kernels are not small enough (broken down) to give access to the starch and proteins to provide an efficient yield.
Heavy Crush – Particles are minuscule, and the husk will be powder. The heavy crush will give you a higher yield, but the powdered husk will not form a filter bed. The tannins from the powdered husks will lead to some harsh flavors. Plus, a great deal of trouble getting the sweet wort from the grain bed. (Stuck Sparge)
The grain bed developed a heavy crush will more than likely become gummy, which also contributes to the stuck sparge.
Brewers compromise by crushing more on the coarse side, creating the least possible amount of small particles (pulverized). Home brewers consider this a good compromise, even with the small loss of extract yield, there are fewer headaches. Plus it is easy to add extra grain to the recipe to achieve the yield required.
As you become more experienced with your equipment, crushing the grain, and the mashing process. Your crushing technique will become fine-tuned to increase your yield.
Mill types
The purpose of a mill is simple: crush the grains consistently. There are two types of mills used by home brewers.
Plate Mills
This is the variety of mill and is used to grind cereal grains into flour. (Not what we want) These are the most affordable of the mills on the market, ranging from $35-$50.
The first type of mill is called a plate mill and is manufactured to grind cereal grains into flour. These are usually the most affordable mills and range in price from about $37 to $50.
As the name indicates these mills have plates (two) usually with a spiral auger that push the grain through a space (adjustable) between these plates.
There are ridges on the opposing surfaces to grip the grains as the plates rotate against the other, thus creating a grinding action.
As indicated above, the distance can be adjusted between these two grinding discs and is essential to a good-quality crush. Adjust the plates too far apart, you will get a heavy crush (large particles) or pushed through without any crush, not good and useless for brewing. Adjust the plates to close together; you will probably get flour and few husk traces also useless for brewing.
For a consistent crush, the brewer will need a constant speed of the auger. A steady speed by hand will be almost impossible; therefore it is best to create the constant speed using an electric motor or drill.
The brewer only needs a couple hundred RPMs and the right adjustment to get the right crush with a plate mill. The need to be always checking your output with the plate mill and checking your adjustment is one of the drawbacks of the plate mill.
Another drawback is the capacity of plate mills, it is very difficult to get an efficient grind when you are required to stop to refill the hopper.
Roller Mills
This is the variety of mill and is used to grind cereal grains into flour. (Not what we want) These are the most affordable of the mills on the market, ranging from $35-$50.
The first type of mill is called a plate mill and is manufactured to grind cereal grains into flour. These are usually the most affordable mills and range in price from about $37 to $50.
As the name indicates these mills have plates (two) usually with a spiral auger that push the grain through a space (adjustable) between these plates.
There are ridges on the opposing surfaces to grip the grains as the plates rotate against the other, thus creating a grinding action.
As indicated above, the distance can be adjusted between these two grinding discs and is essential to a good-quality crush. Adjust the plates too far apart, you will get a heavy crush (large particles) or pushed through without any crush, not good and useless for brewing. Adjust the plates to close together; you will probably get flour and few husk traces also useless for brewing.
For a consistent crush, the brewer will need a constant speed of the auger. A steady speed by hand will be almost impossible; therefore it is best to create the constant speed using an electric motor or drill.
The brewer only needs a couple hundred RPMs and the right adjustment to get the right crush with a plate mill. The need to be always checking your output with the plate mill and checking your adjustment is one of the drawbacks of the plate mill.
Another drawback is the capacity of plate mills, it is very difficult to get an efficient grind when you are required to stop to refill the hopper.
Purchasing a mill
When you decide you need a mill, check carefully the specs given by the manufacturer.
- Be aware of these items when purchasing a mill.
- Roller mills – One, two, or more rollers.
- Are rollers adjustable on both ends of the mill?
- Will the hopper be large enough?
- Are you brewing big gravity beers often? Meaning larger grain amounts, then the larger the hopper, the better.
Just make sure it fits your needs before making the purchase. You will want to talk to other home brewers to see what they are using and why.