Over the past couple of years there has been a growing trend in grinder burr upgrades; manufacturers who produce grinder burrs which are an upgraded version of the ones supplied by the manufacturer. These burrs can often cost a lot more than the standard set which begs the question: is it worth it?
We decided to put this to the test using an entry level commercial grinder, the Anfim Luna. It comes with standard 65mm burrs which cost around £60 to replace. We then fitted a burr set from the sister grinder, the Mahlkonig E65S, which cost around £125 to replace.
The standard burrs have a grinding capacity of around 400kg while the E65 burrs can deal with around 800kg of coffee. Double the money, but double the capacity plus less downtime to change those burrs!
With the standard burrs the Anfim Luna ground an 18g dose of coffee in around 6.5 seconds. Once the upgraded burrs were fitted, the grinding speeds increased by around a second per portion. This will improve efficiency in a busy cafe environment.
The Coffee Experience
We used our Latitude Espresso to compare the coffee made with each burr set. This espresso uses African components and is a relatively light, though well developed roast. We would expect a bright acidity and plenty of sweetness in the cup.
Using the standard burrs we could detect a nice acidity, though not quite as vibrant as we would like. The acidity was also a little muted. There was also a lingering, bitter finish which we didn’t expect.
When we tried the coffee using the E65 burrs there was a noticeable lift in both acidity and sweetness which, when combined, produced a delicious juicy espresso. The bitter finish was not apparent in the cup.
Grinders do not produce even particle sizes. There are always some finer particles than we would want, and some coarser particles. We sieved the coffee produced by the two burr sets to take a look at the distribution of particle sizes.
Standard Luna Burrs
The chart shows two spikes. The spike to the left indicates fine particles which are over extracted in the cup resulting in the bitter finish we experienced. The larger spike on the right would be the particles contributing the more pleasing experiences in the cup – the sweetness.
The most noticeable feature of this chart is the lack of finer particles. There is a greater concentration of desirable particle sizes. These two combined reduce bitterness and explain the increase in the more pleasing characteristics.
Upgrading grinder burrs clearly has positive benefits beyond the performance of the grinder. It seems a small price to pay to achieve a better drinking experience for the customer.