Distribution — The Primary Cause of Channeling.
We’re straight shooters here at Clive. We aren’t here to sell you anything you don’t need, and we’re not afraid to call out gimmicks in the coffee industry. We’ll tell you when something is necessary or overrated (this is exactly something that someone trying to sell you something would say… kidding). Listen up. There seems to be a nearing infinite list of reasons why a shot of espresso could taste badly or pull improperly (more on that in Why Are My Shots Spraying Everywhere?!). Still, the biggest culprit to a bad shot is channeling — and the primary cause of channeling is distribution. We aren’t saying that it’s impossible to get a good shot of espresso by skipping distribution, but we are definitely saying that by doing it, you’ll increase your chances of a more even, balanced, and better-tasting espresso.
First, a few quick things on channeling.
Your shots likely taste bad because of channeling. Channeling occurs when water finds a specific narrow path through the puck of coffee instead of flowing through the entire bed evenly. Over the course of the shot, this path will have a greater flow rate causing some parts of the coffee to over-extract and others to under-extract, resulting in unbalanced flavors. Channeling is easiest to spot with a bottomless portafilter (this is often why people say bottomless portafilters are harder… they aren’t more difficult, they just showcase all the channeling and mistakes!)
We asked our staff at Clive if they thought bottomless portafilters were more advanced. See what they had to say, just for fun.
Signs of channeling:
- A thin jet of coffee spraying away from the rest of the coffee.
- Coffee favoring one side of the basket as it pulls.
- An unsteady, shaky shot (not to be mistaken for a gusher - when coffee is too coarse).
- Gaps in the basket spotted from underneath the bottomless portafilter as it’s pulling.
All will negatively impact your espresso. To learn more about channeling, check out: Espresso channeling - What is it?
As we already mentioned, one of the biggest causes of channeling is distribution.
Distribution is a technique or method in which you level out the coffee grounds in your basket to prepare for an even tamp. This step is crucial and, if done poorly, can harm the taste of your shot. The more evenly you distribute your coffee in the portafilter basket, the less likely you will see channeling.
Distributing the coffee can be done in two primary ways: manually or with a tool.
1. Side Tap
This is our personal favorite technique as it does the best job at moving the entire bed of coffee and not just the top, like other methods often do. Gently tap the sides of the portafilter just a few times to level the grounds. If you tap too excessively, the fines can migrate toward the bottom of the basket, causing some channeling issues, but if you keep it simple and gentle, this method can be most effective.
2. NSEW (North South East West)
Using your finger, push the coffee grounds around in the basket to level it out prior to tamping. This is usually easier to get the hang of compared to the Stockfleth Method but only moves the top half of the coffee bed.
3. The Stockfleth Method
This one of the most common methods and gets you as close as possible to results from a distribution tool without actually using one. It’s very effective at leveling the bed of coffee and used in cafés globally.
4. Using a Distribution Tool
Distribution tools were created to streamline the process and provide as much consistency as possible. They aren’t going to solve all the problems but they can help rule things out and provide a constant variable to the ever-changing millions of other variables.
When should you get a distribution tool?
If your shots are pulling inconsistently and you’ve tried everything on this list:
- Using freshly roasted coffee
- Grinding your coffee each time using a high-quality espresso grinder
- Purging your grinder / single dosing
- Using a scale to keep your dose consistent
- Checking your espresso machine's pressure and water flow rate
- Keeping everything else consistent, , such as pre-infusion, flow control, or tamping pressure.
Check out Tech Espresso Troubleshooting: Is it the machine? Or is it you? for some quick tips on ruling out some of these problems.
Which distribution tool should you get?
The Saint Anthony Industries BT Wedge has been a staple in the coffee industry for many years. It's solid stainless steel with an adjustable depth between 5mm and 14mm. It comes in black, walnut or maple and can even be custom engraved. To get the routine down even more, get the Saint Anthony New Levy Tamp. The tools are available in both 53mm and 58mm.
Newer to Clive in 2022, the Artpresso tool is an easy-to-use, all-in-one barista tool that tamps and distributes coffee. The distribution side goes up to 13mm and the tamper’s maximum depth is 16mm. It’s available in a 58mm diameter.
Do WDT Tools help?
Before we got our hands on the WDT tool, we were haters. Anyone remember this? The Most Overrated Barista Accessory.
So we ordered one from Sworks Design and we pulled shots with and without it and let us tell you something — we were humbled. Our espresso shots were instantly better and we noticed way less channeling. A miracle worker and saving grace to a clumpy grinder. Definitely invest in the Sworks WDT Tool, especially if you're having channeling issues or problems with consistency. A dosing funnel helps keep it all in the basket while you use the tool, so we do recommend the ECM Dosing Funnel as a good pairing.
Distribution begins the moment you start grinding.
Every grinder dispenses grounds into the basket a bit differently — some deliver a relatively even spread with no interference, while others may favor a certain region or be overly focused. Regardless, we recommend helping the grinder out by moving the portafilter in small circles to ensure that coffee is spread evenly across the surface of the basket. This is step one. Help yourself by helping your grinder with the distribution from the beginning.