The tamp is one of the most important parts of your espresso crafting process. You can have a killer espresso grinder, a high-end espresso machine, and fancy accessories, but if you don’t nail the tamp you won’t get great results.
Tamping is also one of the trickiest pieces of the espresso puzzle to get right consistently. Today we have some tips on how to approach it!
Distribution
Before you even tamp your puck, you want to make sure the coffee is evenly distributed in the portafilter. This means that you need to ensure that there’s no mounds of coffee that are higher in one spot than another. If you don’t do this, the density of the coffee will be higher in certain parts of the puck. This can lead to channeling, which is when water naturally finds a path of least resistance through less dense areas of the puck.
The ultimate result of channeling is under-extraction in denser areas of the puc, and over-extraction in the less dense areas. To put it more simply, you’ll get an uneven shot that can taste sour and bitter at the same time.
So how do you solve it? On a simple level, you can gently tap the sides of your portafilter with your hand, and on your tamping mat. This encourages the coffee to spread out gently and naturally around the portafilter. Note that you’ll want to avoid using the side of the tamper, as the metal on metal contact will create more of a shockwave rather than a gentle distribution.
You can also invest in tools, like this option from St. Anthony Industries. There’s also a growing interest in stirrers that use clusters of dull metal needles to distribute the grounds and break up clumps. We think you should do what works best for you! The key is just ensuring even distribution around the portafilter.
Grip
It’s also important to work out a proper grip and stance when tamping. You want to hold the portafilter firmly, but without straining your hand. We find that gripping it a bit like a doorknob is the way to go.
You also want to properly position your body for the tamp. You should position yourself over the tamper so that you can push down without any strain or discomfort, and so that you can apply pressure to the tamper evenly.
One thing that can help with positioning your body and the portafilter comfortably and effectively is to purchase a tamping station. Normal tamping mats are great, but with a station that has a raised platform you can sometimes get better leverage depending on your own ergonomics.
The Tamp
Of course, the most important part of the equation is the tamp itself. You might already know that you want to apply 20-30 pounds of pressure to your puck, but what does that feel like? How do you know how much you’re applying? Unfortunately there’s no easy answer.
There are calibrated tampers you can get, like this option from St. Anthony Industries, and some that provide a “click” when you push down enough. These can be really great tools for learning the feel of that perfect tamp. That said, you can also get there by practice and seeing how your espresso tastes after the tamp.
If you have a sensible grind size then you can zero in on your tamp as the inconsistent variable from shot to shot. It can take many shots to get there, but eventually you’ll start to feel just the right amount of pressure.
It’s also important to tamp evenly. So if your tamper feels like it’s not level after your tamp, give it a gentle push to level out the bed of grounds.
Finally - we find that “polishing” your puck, or giving the tamper a twist at the end, can actually unsettle your grounds bed and undo your hard tamping work, and it doesn’t really provide any benefits to the shot. In our opinion, it’s best to avoid that twist.
Common Tamping Mistakes
We’ve talked about some of these above, but if you’ve still got questions about your tamp then we have a great video just for you! Check out John’s list of common tamping mistakes below.
