Like any important piece of equipment, keeping your grinder in tip-top shape is a necessity to ensure you have a properly working grinder for a very long time. One of the most important components of your coffee grinder is the burrs.

What is a coffee grinder, Burr?

A coffee grinder burr crushes coffee beans and pushes them through a small opening between the two burrs in your grinder. Some grinders use flat burrs & some grinders use conical burrs.

Read our article on the difference between the different types of grinders.

Whether you have a coffee grinder with conical or flat burrs, you must clean them on a regular schedule so they continue to work optimally at grinding coffee consistently. If you have been cleaning them regularly, have had your grinder for quite some time, and have noticed some changes in the coffee, it may be time to change out the burrs!

Why do you need to replace the burrs on your coffee grinder?

Changing your burrs ensures your grinder is working efficiently and higher levels of extraction are more achievable, which means you’re brewing better coffee. Not changing your burrs will most likely result in negative changes in your brew. You could be getting a lot of fines in your brew and tasting off-flavors or muddled tasting notes. It could even affect your pocket because you may have to increase the dose of your coffee or use more than normal to adjust for the flavor and thus resulting in going through coffee more quickly. Taste is everything, so noticing these changes is also insight into your equipment.

What is the expected lifespan of a burr set?

There are a lot of differing opinions as to the frequency of changing out the burrs. Some burrs place priority on the number of pounds of coffee grounds and some prefer to have a hard date regardless of when to change them out. Here we have a few things that can be positive signs that your burrs need to be changed out.

How to tell when you should replace the burrs in your coffee grinder

Here are a few things that you can keep in mind when dealing with the current burrs in your grinder.

The Burr edges become dull

Since you are cleaning them on a regular basis, you can feel the sharpness. When they start to feel dull, then you know it’s time to change them out.

Consistently having to increase your dose

If you find that you’re having to grind finer or increase your starting dose to achieve a similar flavor, then that’s a clear sign of dull burrs. You also may have noticed the brew time changed and brewed quicker like an espresso shot.

Inconsistent Particle Size

As the burrs become dull, they will start to grind inconsistently and you may be able to notice a high level of variation. Keep in mind, that all burrs will produce a range of particle sizes, even new ones. However, you want to see one size that is consistently dominant. Inconsistent particle size (like a blade grinder!) will result in an uneven extraction and thus you will taste more muddled, sour, or astringency in the brew.

Decrease in Extraction

A straightforward way to tell your burrs are dull is by measuring the TDS ( total dissolved solids) with a refractometer. If you use a consistent recipe to brew coffee and measure TDS regularly, over time, you will notice the extraction decrease because the burrs are becoming less sharp. Coffee particle size starts to increasingly vary as the burrs become dull.

Clumping of Coffee Grounds

This applies more when grinding for espresso but can also happen with larger grind sizes. When your coffee grounds start clumping, it can ultimately affect the taste of your espresso, turning it bitter, by producing inconsistencies in your portafilter. However, there are some tools that you can use to help break up those clumps like The Comb from Barista Hustle.

Conclusion

Maintaining clean burrs will ensure quality enjoyable brews. Burrs can last a very long time with proper upkeep and maintenance. However, the taste is something that you will want to be in-tuned with your coffee, so you know when the time has come for replacement.

Of course, the manufacturer will have information on their recommendations so also keep that in mind, unless you prefer a regular burr replacement schedule. In that case, you are less likely to notice taste differences and you would be ahead of the degradation. Whatever is your preference, understanding that burrs don’t last forever and they have to be replaced when needed will make sure your getting quality brews to enjoy.