Okay, so I’m going to be very honest with you. When I first learned how to make coffee, I was pretty confident that I’d nail it. But then I got behind the machine and actually started making an espresso. Did I nail it? Well, let’s just say, I didn’t pull the famous “god shot” that baristas obsess about. That shot was less than average.
Preparing an espresso is a simple process, once you get the hang of the variables and use the right equipment. Once you understand how to play with tamping, grinding, dose and extraction time, you will be able to customize the taste of your shots to your liking.
This page is an introduction to the art of pulling an espresso shot. If you have some experience with brewing espresso, this might not be for you.
What Is an Espresso?
An espresso is a concentrated “shot” extracted from finely ground coffee, pushing water under high pressure in a short amount of time. It is identified by a foamy brown substance called crema. It is slightly bitter in taste and floats atop a darker liquid which carries most of the flavor and tends to be sweeter.
The crema is what makes espresso special, and it gives your shot personality. It looks nice but more than that it gives your coffee its great aroma and taste. It also plays a pivotal role in your milk-based beverages as it makes your latte art much easier (a bit more on this later).
What Are the Variables that Influence the Taste of Espresso?
Let us first discuss the key factors that make or break your espresso.
The grind is how fine or how coarse you grind your coffee beans. When you make an espresso, you need to grind very finely. Adjust the grind size to a table salt comparable size. The finer you grind your beans, the longer it will take for water to be pushed through it. The coarser you grind your beans, the less time it will take for water to run through your coffee.
The dose is the weight of dry coffee beans you dispense into your portafilter. Check the weight of the portafilter basket and dose within 1 to 2 grams of the weight. We recommend using 17-20 grams.
This is one of the most important variables as it evens the out the grounds and compresses them. You shouldn’t tamp too hard as this will create too much resistance for the water to pour through. Neither you should tamp too light as the water will pass through too fast, resulting in a weak shot.
When you turn your machine on, wait for it to heat up before you start playing around with it. The temperature is usually around 90 degrees. The water needs to be hot enough to absorb the flavors of the coffee.
This variable is the most important difference between espresso and alternative brewing methods. When we speak about pressure in espresso, we are usually referring to 9 bar pressure. The 9 bar pressure creates enough force to break the resistance of the compacted grounds created by the tamp. The pressure pulls the flavors out. The more pressure exerted the more flavor you’ll extract.
Many espresso machines have a pressure gauge, usually located at the front of the machine. You can read on the gauge the pump operating pressure. This is an important part of the machine.
Last but not least, check the cleanliness of the machine. Particularly the portafilter and the group head. There should be no trace of old coffee grounds left in the portafilter and the group head. Use a cloth to wipe the group head and then flush the group head by turning the water on and then off.
Now that you know the variables, let’s make coffee!
Why a Pump Espresso Machine?
We have an article about alternative espresso brewing, but if you want authentic espresso, a pump driven espresso machine is the right equipment for you. The pump espresso machine has the 9 Bar pressure needed to push the water through the compacted coffee grounds. Other methods are nowhere near that force. The pressure does a few great things to your coffee. Here are a few of them:
- Allows more soluble solids to pass into your cup
- It shortens the brewing time
- Lowers the brewing temperature, and permits colder brewing
- It emulsifies the oils into your coffee
Low-pressure coffee makers, such as moka pot, or steam espresso makers, cannot produce crema, and there is a higher risk to burn the coffee, (over-extract). At the same time, a good espresso machine will create a beautiful foamy layer, that is both aesthetic and tasty. It adds a new flavor dimension to your shot. If you think you cannot afford a pump driven machine, take a look at these inexpensive espresso machines. You’d be surprised at how affordable some of these units are.
How to make an espresso using an espresso machine
a. Prepare Your Machine and Equipment
- Fill up your water reservoir.
Open the water reservoir and pour distilled water in there. If you’re a beginner, your water quality may not be as important as getting the steps right, but as you advance and start to play around with flavors and espresso quality; water will play a huge role. In fact, the best is spring water, but using distilled is more convenient because you don’t need to descale as often. But this is another discussion.
- Heat up the entire machine.
Before you start using your machine, make sure the water in the boiler has the right temperature. All the espresso machine have a light that indicates when the water in the boiler is hot. The worst thing you can do is pull a shot with lukewarm water. This will give you a weak, under-extracted cold espresso shot. Yuck!
- Check your equipment.
Wipe your portafilter with a clean cloth to remove any remaining coffee grounds and flush your group head to drain residue off your machine. If your machine and portafilter aren’t clean, the taste of your espresso is at risk of being bitter and over-extracted. Cleanliness is probably one of the most neglected aspects. But let me ask you this: “Would you drink from a dirty cup?”
Prepare your beans
- Dose your coffee
Using a scale, weigh the entire weight of the portafilter and lock down this amount in the memory of your scale. Now grind your beans under the coffee grind dispenser. Keep tapping the portafilter lightly to evenly distribute the beans in your portafilter. Place your portafilter on the scale again to check the dose of our coffee. The more grounds you use, the more resistance you create in the coffee puck. Because of this, it is very important to get the right dose.
If you absolutely dread the idea of weighing coffee beans, (I’ve seen that before), then measure with a scoop.
- Give it a good tamp
Once you’ve dosed your beans, use your finger to spread the coffee grounds around your portafilter. This step creates an even bed of coffee grounds in your portafilter to make sure your tamp is as even as possible. Place your palm on top of the knob of the tamp, grab the tamper and place your thumb and index finger on the top edge of the base. With your elbow at a 90-degree angle and your forearm in a straight line with your wrist, push the tamp down on your bed of coffee allowing your fingers to kiss the rims of the portafilter basket. Give it a gentle twist and lift the tamper. For more advanced tamping techniques that real baristas use, check the Stockfleths Move. Finally, wipe the rim of the portafilter to remove any trace of dry, loose coffee grounds.
Tamping should be the variable that doesn’t change. Think about it: if you change 3 things at the same time, and you get the perfect shot, how do you know
Prepare to Pull the Shot
- Prepare to pull
Weigh your espresso cup on the scale and lock in the amount. Flush the group head (if you haven’t already) and lock the portafilter into the group head. Push the button to release water and press the timer at the same time, (if your machine has one). A timer or the stop clock on your phone will also do the trick!
There are two things to look out for at this stage. First, you could go by the time it takes to extract a shot, or you could go by sight – which means you observe the change in the color of the crema. If you go by time, the standard extraction time is somewhere between 20-30 seconds for a shot. Alternatively, look at the color of the espresso. It will start to drip a dark brown color. Then it will go from a reddish brown to a medium brown and finally a golden brown color. In barista language, this is called blonding. At this point, your espresso is fully brewed so stop here. Any further brewing will cause your espresso to be over extracted and thus taste bitter.
One more thing, no matter what size you pull, a solo or a doppio, the extraction time is the same. That means you need to adjust grind size to restrict the flow for a solo, whereas you grind coarser for a doppio, to compensate for the thicker coffee puck.
That’s it! Make sure you keep practicing getting the flavor, the timing and your tamp right.