When you are looking for a new coffee grinder, one of the common details listed will be the material for the grinding burr. The two I’ve seen the most are ceramic and hi-tempered or stainless steel.
Having a degree in Engineering and coming professionally from a manufacturing background, I always like to understand why certain designs use a type of material.
When I researched these two commonly used materials, it all started to make sense to me.
I’ve listed the pros and cons to each material, and theoretically why you will see them used where they are. Check this out:
Ceramics are an inorganic, nonmetallic material consisting of metallic and nonmetallic elements.
Think of them similar to glass.
They are typically molded into their final shape, and hold accurate dimensions well. Ceramics are high-strength, but brittle. They are typically very hard and don’t conduct electricity well. They won’t rust or oxidize, which makes them good for use in things that can get wet or washed with water. They also handle heat very well and won’t retain a lot of heat (or conduct heat) if exposed.
All of these properties make them a good use for a manual grinder that runs off hand power. You won’t spin them at high speeds using a hand crank, which makes them a long-lasting durable option.
While the ceramic sounds like a great material to use, it does have a couple drawbacks. One of the drawbacks can be cost.
There are low cost options in ceramics, but some higher-end hand grinders may use an extremely durable ceramic that could cost more to produce.
As mentioned, they are also brittle. They won’t handle an impact well, and low density ceramics can break when they are hit with a high impact.
You won’t think a coffee grinder would be an issue, but imagine if it jammed. Something will give, and it could be the grinding burrs if they are low quality.
One last drawback to mention is that they may not handle a thermal shock well. Think of it as changing temperatures quickly. Cold to hot, hot to cold, etc. Low quality ceramics can crack when changing temperatures quickly.
Stainless Steel Burrs
Stainless steel is obviously a metal, so if you are familiar with the properties of metal then you know what to expect.
What makes stainless steel different from a standard metal is that it has chromium mixed in, and potentially molybdenum. The chromium will resist corrosion (rusting and oxidation) and the molybdenum would help resist acidic corrosion.
Steel is easily formed, either through casting and/or machining, and makes it a good choice for applications involving food and drink because of the anti-oxidizing properties. It will also handle high-impact environments as in a high-speed grinder attached to an electric motor.
After reading how great stainless steel is, you would think it must be the best material to use in every situation.
One of the drawbacks of a stainless steel is heat soak. Metals, even stainless steel, will absorb and retain heat. When grinding a large amount of coffee, the burrs can heat up and then transfer that heat to the beans.
You may be roasting the beans while you’re grinding them. That’s more of a worst case scenario, and not a daily occurrence.
They will expand more than a ceramic burr in a hotter environment, and they tend to have shorter lifespans requiring replacement more frequently.
Can I Pick and Choose Between Which Burr to Buy?
When you look at a new grinder, most of the time you don’t have a lot of choice in the burr depending on the model. Most manufacturers list what burr is used, but don’t offer a custom design option that would allow you to pick grinder styling A with a choice of which burr is included.
What you can do is find a few different designs that you like and they pick the burr that matches the style of coffee you enjoy most.
For example, the ceramic burr does well in a hand grinder that would be used for espresso mainly. If you’re more in the mood for a quick cup of coffee, maybe an electric grinder with a stainless steel burr is just what you need.
You can see some of our favorite manual grinders here for some good ideas.
What Should I Do?
For the average coffee drinker, the choice of which burr to look for is probably not something that will sway you one way or another.
The things you’ll search for are a manual or powered option, and what styling you enjoy in the grinder itself. You will probably leave the choice in materials of the burrs to the design experts and manufacturers.
Here are some of our favorite electric burr grinders to give you more good ideas.
But, if you’re like me and enjoy knowing why things are designed and put together the way they are, you’re still probably interested to know which grinder burr was chosen for your favorite grinder.