September 27, 2016

Mahlkönig EK 43: How to Avoid On-Demand Dosing Issues


The Mahlkönig EK 43 might just be one of the most revered coffee grinders in the specialty scene. Yet while it’s become a fairly common sight in third wave coffee shops, many still have reservations. In fact, relatively few places have abandoned traditional grinders entirely in favour of it.

For some, it’s the EK’s lack of an on-demand dosing option that gives them doubts. Others baulk at its cost, especially if multiple grinders are required.

Yet for me, neither concern has to be a deal-breaker. Here’s how I make it work for my shop.

Spanish Version: Mahlkönig EK 43: Cómo contrarrestar la falta de dosificador 

EK 43 grinder on the bar

Fitting the EK 43 into the shop workflow. Credit: Daily Coffee Stand

It All Comes Down to the Single Dose

One of EK’s main advantages is that it can grind single doses with no loss of grind quality or evenness (when compared to grinding with a full hopper). What’s so great about this? It opens up the possibility of running multiple coffees without having a separate grinder for each one. The only limitations are how many coffees you wish to dial in and offer.

This makes the relatively high purchase price of the machine look much more reasonable. One EK could take the place of several traditional grinders – in fact, in my shop Repack Espresso in Bath, I replaced three grinders with it.

But that’s not the only good reason to single dose. Coffee beans fracture less evenly when ground at higher temperatures, according to a 2016 article in Nature by Erol Uman et al. And when uneven fracturing happens, it causes changes in flow rate – leading to a decrease in coffee quality during busy periods.

This suggests there’s a significant benefit to single dosing. The majority of the beans will be removed from the heat source (in a sealed bag or in pre-dosed portions) and so the overall temperature during grinding is lower. The espresso will be more evenly extracted and, in turn, tastier.

If you’re thinking “Ah! But there’s a big downside to single dosing: much slower workflow!”, you’re right – to some extent.

There’s no escaping the fact that using an EK in this way won’t be as fast as the best on-demand grinders. However, just a few little tricks can reduce this difference. Here’s how we do it in my shop.

A double EK 43 grinder

The EKK 43: double the EK. Credit: Mahlkönig UK

Practical Ways to Single Dose

We’re a multi-roaster shop and we run 2–3 single origin espressos and 1–2 filters, all of which we rotate regularly. They’re all ground on our EK 43, which is equipped with “coffee burrs” (more on this later).

30 minutes before opening, I measure out sufficient doses of each bean to last through the morning’s service. I do this using espresso cups, my Ohaus bench scales, and an AeroPress funnel (to stop beans missing the cup and falling on the floor). Each dose will be 0.5 g more than needed to account for retention. The doses are then placed near to the grinder (I find small spice jars work quite well as containers) until needed.

When somebody orders a coffee, the barista first empties the EK of any retained grounds (which we find is mainly parchment). They they move the grind to the appropriate setting for the beans and dose into a 125 ml metal wine measure, which fits precisely over the dosing mechanism. The dose can then be transferred easily to the portafilter, with a quick tap to loosen any grounds that have stuck to the measure.

From then on, making the espresso is the same as with any other grinder – although it should be noted that the EK produces its best espressos when the shots are pulled longer. We typically run 15 grams in and 34–40 grams out.

EK 43 grinder on the bar

Brewed takes the idea of a “practical workspace” to the next level. Credit: Brewed

SEE ALSO: Everything You Need to Know About Mahlkonig’s EK43 Grinder

Pre-Dose to Save Time

The process of pre-dosing does take time. How much? Well, with practice, 100 or so doses will take about 20 minutes. This is partially offset by less wastage: with only 0.5 g of retention, dialling in is much more efficient. There’s no need to discard large amounts of coffee with each change in grind setting. Ditto for any changes made to grind settings throughout the day.

In-service use of the EK is a little slower than with a traditional grinder, as more actions need to be followed – but this, again, is partly compensated for by the speed of grinding. The large, flat burrs are astonishingly effective in this respect.

Barista using EK 43 grinder

Finding a workflow and routine that works for your café. Credit: Cottontree Coffee Roasters

Changing Grind Settings: A Case of Human Error?

There is one final downside to the EK – changing grind settings between coffees. Like all grinders, different coffees will have different optimum grind settings. With the EK, single dosing necessitates that the barista ensures the setting is appropriate for each individual dose rather than relying on the grinder being pre-set to one coffee, as in a more traditional setup.

In practice, this can be mitigated by familiarity. Also, make sure that there are written reminders of the settings for each coffee in the grinder area. Mistakes will still be made, but the more your baristas use the EK, the less frequent they will be.


A different grind setting for every coffee. Credit: Muhammad Mirza

A Question of Volume

With a good workflow in place, a single EK can easily deal with 100+ coffees an hour. Beyond 150, however, and you might want to consider a second grinder – especially if you wish to offer filter coffees.

Below this level, it’s still possible to use one EK to grind for both espresso and filter – but you’ll need to specify “coffee burrs” rather than “Turkish burrs” when ordering it. The latter can grind finer but aren’t as suitable for filter coffee, whereas coffee burrs can be set to produce great filter and espresso.

We should say, though, that while we’ve never experienced issues grinding fine enough to extract all of our coffees properly with the “coffee burrs”, some machine/water chemistry/bean combinations may favour the “Turkish burrs”.

Kuppie Coffee

Serve filter and espresso? You’ll want coffee burrs. Credit: Vincent Guang of Kuppie Coffee

More Practical Considerations for the EK

To ensure consistency, we always start with the hopper flap closed, turn the grinder on, and then open the flap to let the beans fall onto the moving burrs. This is supposed to lessen the pressure on the shear plates, which are designed to fail in the event of a foreign object making its way into the grinding mechanism.

It’s also worth ordering some spare shear plates just in case this happens, as a breakage would result in the grinder being out of action. This is especially bad news if the EK is your only grinder.

Burr alignment and calibration are also critical on the EK. The latter is especially important when using “coffee burrs”, because you need to ensure that a sufficiently fine grind for espresso can be achieved. Correct alignment, on the other hand, is crucial for an even particle distribution; even a slight misalignment can yield a significant decrease in the quality of the coffee. Both of these areas have been covered widely elsewhere, so I won’t go into them in detail here.

Exploded EK 43

Exploded EK 43, with shear plates part 27. Credit: Mahlkönig UK

The EK 43: Yay or Nay?

Of course, the EK isn’t for everyone. If, for example, you’re a very high-volume shop selling a single house espresso, then its upsides are more than outweighed by its downsides.

However, if you’re a low to high-volume shop that wishes to offer a range of beans, and the highest quality espresso and filter currently possible, then the EK 43 offers a lot of advantages. In fact, I’d say that it should be the first item on your shopping list.

All views within this opinion piece belong to the guest writer, and do not reflect Perfect Daily Grind’s stance.

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