Good espresso preparation is all about the details. Details like controlling the dose going into the portafilter using scales. Details like measuring the yield being extracted by programming volumetrics or using scales on the drip tray. Details like making appropriate adjustments to your grinder to hit that magic 30 seconds for consistently great espressos (give or take a few seconds).
You got it ... when it comes to the perfect brew, every detail matters!
But you can hit all these metrics and still produce an espresso which is disappointingly average. Rage! So, what gives?
The answer lies quite possibly in how effectively you’re distributing your coffee into the portafilter: it's surprisingly hard (but crucially important!)
Once you’ve locked in a loaded portafilter and hit that brew switch, a flow of pressurised water will hit your bed of coffee and try to cause trouble. Be aware, this is crunch time – all the preparation of growing, sourcing, roasting and grinding your coffee will either be celebrated or made redundant in this little basket where water meets grinds. An even distribution of grinds within the basket will force the water to behave and deliver you a quality, predictable result. But the trick is to manage that, each and every time you brew.
It's important here to note that once your coffee is in the portafilter, you need to ensure that the grounds are spread evenly around the basket before you tamp. Tamping only distributes the top of the bed of coffee, not the bottom!
A good distribution technique will help you to achieve an even extraction of your coffee and avoid channeling. Ideally, you want it to be as repeatable and effective in a busy café environment as in a lab or at your home coffee station.
So about that technique…
There are two things we’re focusing on here. First, the easy part – getting the coffee into the portafilter. You want to hold the portafilter so that as much of the coffee as possible ends up in the centre of the basket. Depending on which model of grinder you’re using, this is either really easy or a bit of a challenge. Some grinder models tend to dump the coffee off-centre: first, try moving your portafilter and angle it to achieve the most central distribution during grinding. If you're using a manual dose grinder, play with the speed that you pull through the dosing lever to help control how and where the coffee is thrown out of the chamber. If the result is a little asymmetrical, don't sweat it at this point.
If you’re using a funnel or dosing cup to dispense grounds into your basket, you might get a lot of coffee on one side of the basket. Give the portafilter a swift circular shuffle to neatly spread the coffee around the basket. give the portafilter a swift circular shuffle to neatly spread the coffee around the basket. Like so:
In a perfect world, you now have a perfectly flat bed of coffee and you are ready to tamp. But, let's say it's not yet quite perfectly flat and horizontal, what's next? There are certainly a number of different approaches to this issue out there. In this article, we will focus on two different techniques: tap distribution and stockfleth with the option to use a distribution tool at the end of each technique to create the perfect flat bed of coffee.
Tap distribution
The following technique is the approach we teach at our Academies, in our Fundamentals: Espresso & Milk course, as we've found it delivers the most consistent and delicious results, shot to shot. But it's also easy to repeat and speedy to perform - so you can deliver the results when the docket line is piling up.
To tap distribute your coffee, take an empty portafilter and place your ground dose of coffee in the basket using the most effective method for your grinder and workflow, as mentioned earlier. Once you have the dose of coffee in the basket, it's time to tap.
Hold the portafilter in your non-dominant hand and with your dominant hand, tap the basket side of the portafilter five or six times until the bed of coffee has levelled out and is nice and flat. The nuance of this distribution method is in how hard you tap, how many times you tap, how you hold the portafilter whilst tapping.
First up, when you’re tapping the side of the portafilter you need to hit it hard enough to encourage the ground particles of coffee to move about. If you tap too softly, the ground coffee will not move, meaning that the coffee essentially remains undistributed. Use the palm of your hand, not your fingers. If you tap too hard on the other hand, the coffee will just fly straight out of the portafilter basket! We're aiming for the middle ground here.
At the same time, you want to be nice and consistent with regard to how many times you tap the coffee. As you tap the portafilter, the coffee grinds move around and down. The coffee moves a little more and starts to get compact on one side of the portafilter if we tap say 15 times compared to 10 times. Ultimately, you want to be consistent. We’ve found that you can consistently distribute your coffee in five to six taps.
Next up, you need to move the portafilter around as you are tapping it to ensure it creates a flat surface. If you hold the portafilter perfectly flat and tap it, the ground coffee will just bounce in one direction making the distribution even worse. To compensate for this, as you are tapping the portafilter, hold it on an angle so that the highest point of the basket is where you are tapping and the lowest point is the opposite side of the basket. Essentially, if you hold the basket on an angle, the ground coffee will be moved to the lowest side of the basket as you tap.
Let's recap: you had a hill of coffee grounds on the left side of the portafilter. You want the coffee to evenly distribute to the right. You must then incline the portafilter and tap distribute to even out your coffee bed.
Once the coffee is evenly distributed, it’s time to collapse it by tapping it downwards onto the bench. When doing this, ensure that the basket of the portafilter is perfectly flat and you are moving with a straight downwards motion.
On many portafilters, the angle of the basket is different to the angle of the handle, so a barista who is holding the handle of their portafilter flat is actually holding the basket on an angle. Therefore when they tap down, they are not creating a perfect downwards force on the coffee. Keep this in mind and ensure your basket is perfectly flat and moving straight down for your collapse. Your collapse doesn’t need to be a super hard smack on the bench. Just firm enough to move that coffee down.
One extra step you can add here is using a distribution tool to allow you to create an extra flat bed. Our recommendation here: spin it 3-4 times, but feel free to try it out!
Side note: keep in mind that distribution tools only distribute the top of the bed of coffee, not the bottom so make sure you tap distribute your portafilter beforehand if you use a dosing canister or your grinder delivers the grind off centre.
Stockfleth
Aka - distributing with your fingers. For this one of course, you want to make sure your hands are always clean! This technique is traditionally used when your grinder dispenses the coffee perfectly in the middle of the basket (you have a nice mountain of coffee grounds in the middle), and you do not use a dosing canister. In this scenario, the bottom of the bed of coffee is well distributed and only the top needs a little help. Check out Chris Baca's video for a fantastic Stockfleth tutorial here.
Many techniques exists here, but the goal is to have a flat bed of coffee as quick as possible so find a technique that is efficient and easily replicable!
Time to tamp!
Once you’ve distributed your coffee, it’s time to tamp it. Once again, there’s a real emphasis on flatness here. Ensure the tamper enters the basket of the portafilter as level as possible and moves straight downwards. You don’t want to enter on an angle and correct it later because you’ve already changed the distribution of the coffee by that point.
A lot of people will ask how hard they need to tamp. Historically, baristas have put a lot of emphasis on how hard you need to tamp, even going to such lengths as practicing the pressure of their tamping on a set of bathroom scales. Some baristas will tell you that 15kg of pressure is necessary, others will say 25kg or even 10kg. In reality, it doesn’t actually matter that much. You can only compress a solid so far (unless you’re a hydraulic press) so it’s quite easy to tamp hard enough. Just push down until you feel the coffee pushing back against you. Make sure you tamp only once ... or twice ... as long as your technique is consistent. Once again, consistency is key to a consistent extraction of espresso!
Once you’ve done all this, how do you know if you’ve improved your coffee making or not? Well, it’s time to do some taste testing! If you control all your other variables and only change your distribution technique, you can taste several espressos and compare results.
Make several espressos, one where you do not distribute and one where you employ our tap distribution method, and then add any other distribution methods you’re interested in testing, like stockfleth, needle tools, etc. When your shots are pulling in a time that you know should taste good, start tasting the different espressos. We’re looking for the shot with the most balance, due to the water extracting as much even deliciousness from the coffee as possible. Better prepared espressos will taste sweeter, richer and less sour – and they will have a pleasing balance between acidity and bitterness.
Tap distribution hits all these marks and ensure a greater water flow through your bed of coffee. Give it a try!
