Espresso is a lovely way to drink coffee. Every part of the process is worth celebrating; the preparation, the process, and the drink. Most espresso-lovers soon discover that without proper focus on preparation, there are consequences on the final shot. One of the critical steps is to prepare your puck for the next stage; brewing. This involves everything that happens from the moment your coffee exits the grinder to the moment you place your portafilter in the machine. Here’s where individual skill comes into play. The difference between a good espresso and a bad one could possibly boil down to puck preparation.
A good puck is one where coffee is extracted as evenly as possible. This lets us use less coffee for similar or often better results. With little to no room for over-extraction, the coffee is naturally sweeter and less likely to taste bitter. A good puck has a flat surface along with even density and distribution of particle sizes throughout. The appearance of the puck after brewing doesn’t give us much information about our puck but we can use a bottomless portafilter to evaluate the distribution and tamping technique.
Here are the factors that make a difference in puck preparation quality and ultimately your final espresso:
Ross Droplet Technique (RDT)
For this technique, all you need is a small spray bottle filled with water suitable for brewing espresso. Before adding your beans to your coffee grinder, add one spray of water over your beans, and gently shake the beans for the water to spread uniformly It helps reduce static and coffee retention in your grinder. This means that your grinder output is more likely to match the input without any grounds left behind. Back in 2005, David Ross pioneered a revolutionary technique that has since been called the Ross Droplet Technique (RDT).
Weiss Distribution Technique (WDT)
Distribution is perhaps one of the most important factors to keep track of. When you first add ground coffee to the portafilter, coffee is not evenly distributed. There’s a mound of coffee with lots of grounds in the middle and barely any at the edges. Tamping at this stage won’t produce an even bed of coffee. Depending on the type of beans and roast level, ground coffee can be in clumps after grinding. If we brew right away, water can get through the thin parts of the bed with ease, and barely or slowly through the dense parts of the bed thus over-extracting or not extracting the whole set of flavors. The same effect can happen if the grind size is not uniform which often happens with blade grinders.
The best way to overcome this problem is to use a WDT tool. By doing so, the bed of coffee is evenly distributed, and any coffee clumps are broken apart. The WDT tool consists of several thin metal needles that are placed into the bed of coffee and stirred around to ensure even coffee distribution from the base of the basket to the top. The WDT is named after John Weiss, who developed this technique back in 2005 as a way to compensate for grinders that produced excessive clumps.
Tamping is often the last step of espresso puck preparation. A traditional tamper requires some focus on ergonomics. The goal of tamping isn’t to exert a lot of pressure onto the bed of coffee, but rather to push the air out of the coffee grounds. In fact, applying more pressure does nothing to improve your shot. While tamping, make sure that your wrist and your elbow are perpendicular to the surface you’re working with, like you’re holding a screwdriver pointing downwards. An even bed is paramount for creating a uniform brewing environment.
Another option for tamping is a force tamper that alleviates some of the anxiety involved in the tamping process. For one, the force tamper is designed to sit on the basket ensuring a perfectly level tamping surface every time, and two, the force tamper doesn’t allow more pressure after a certain threshold is reached. Forced tamper is not a must.
This puck preparatory tool also has a set of needles. But these needles aren’t for distribution. The time to use your Porcupress is after using your WDT tool and before tamping. The Porcupress is placed upon the portafilter containing your well-distributed bed of coffee. After doing so, push the needles down once, then rotate your Porcupress a little and push the needles down once again. This step creates several tiny holes in the bed of coffee. After tamping, there’ll be numerous pathways in the bed for water to pass through allowing for even extraction throughout.
Paper Filter & Puck Screen
Paper filters were initially introduced to remove some of the lipids in coffee. The efficacy of lipid reduction is somewhat argumentative. Still, paper filters reduce a portion of the oils and lipids in your espresso along with any fine particles that may otherwise get through the basket. A puck screen on the other hand is a thick metal mesh designed to sit on top of your puck. They act as an aid to improve water distribution for the bed of coffee. Another benefit of using them is to avoid excessive puck expansion during pre-infusion which creates a more even extraction later.
Before you begin puck preparation for your espresso shot, it’s good practice to weigh your beans. This is especially true if you’re using a new grinder. Not every grinder has zero retention, which means that there will be some losses. Measuring the bean input and output will help alleviate this uncertainty.
If you had to choose just one of these tools, we’d recommend the WDT tool (or a puck rake). The order after that would be RDT, PorcuPress, Force tamper, and Paper filter/Puck screen. The path to great espresso is rewarding, fun-filled, and informative. Every time you prepare a puck for your shot, you learn something new. And with each espresso you make, you’re working with the knowledge of all the shots that came before this one. Once you understand what you like in your espresso, getting your perfect shot is just a matter of time. If you’re looking for a place to start, here’s our recommended reading.
We see a lot of coffee lovers think it’s all in the espresso machine and grinder but that’s only a part of it. Indeed, good machines and grinders help extract the most flavors but your choice of coffee should matter too. So make sure to pick the best single-origin coffee and roast it light for nuanced flavors. Good coffee beans are a prerequisite to all of this.
If you’re yet to decide on an espresso machine for your home, these are our top picks.