Got a new espresso machine and aren’t completely sure how long it should take to finish pulling one shot of delicious espresso? Here’s what you want to know.
A good shot of espresso should take 25-30 seconds to pull from starting the pump until getting 30 gram of liquid in the cup. The amount of time is just a benchmark to check if you got the flow rate right which in turn is an indication of extraction. There are many factors that impact flow rate.
It’s a complicated topic so let’s get into the details so you can understand what to expect and how you can change the time it takes to pull a good shot of espresso.
How Long Does It Take To Pull A Shot Of Espresso?
The target duration for a shot of espresso is 30 seconds. Although anything from 25-35 seconds can produce good results. This is the time from turning on the pump until you’ve got the desired amount of liquid in the cup and stop the pump.
Is a 30 seconds shot the end all be all of espresso? If you hit 30 seconds and turn off the pump, do you have the perfect espresso? Sadly, it’s not that simple.
A single shot of espresso usually weighs around 30 grams. That means you don’t just run the pump for around 30 seconds, you want to get 30 grams out of the machine in 25-30 seconds. So the time is an indication of flow rate and extraction.
If your shot takes longer or shorter, the flow rate and extraction are probably not in the ballpark to brew good espresso and the shot will likely taste less than perfect.
There are many things you can change to change the flow rate and therefore the shot time. Getting 30 grams of liquid in 25-30 seconds is a benchmark that shows you did everything right before starting the pump. It means you got the grind size, puck prep and tamping pressure right.
Let’s take a look at the factors that change the amount of time it takes to get 30 grams of liquid through a puck of ground coffee.
What Changes Espresso Shot Time?
So the roughly 30 seconds for an espresso shot is a kind of benchmark. It’s mainly a benchmark of if the puck of ground coffee in the filter basket provides the correct amount of resistance. Or at least the amount that usually leads to the right extraction and therefore good taste.
There are many factors that impact the flow rate through the puck and therefore how long it takes to get +- 30 ml of liquid into the cup.
Can you pull an espresso shot faster? Click here to find out.
The biggest impact on shot time is the grind size. The finer the grind size the longer the shot time. The finer the coffee particles, the smaller the gaps in between them and the harder it is for the water to get through which is why it takes longer. The resistance becomes higher and the water flows slower.
One important thing to understand is channelling. Once the resistance of the puck is too high, the water will find the weakest spot in the bed and start flowing there. You want the water to flow through the whole puck, not just a single spot. Because when the water just flows through a single spot, the water will erode the puck and dig a little tunnel (channel) in the bed. That is obviously bad since that means the water doesn’t extract any of the grounds. The water will flow faster and extract very little.
Another issue is the particle size distribution of the coffee grounds. You want all the particles to be close to the same size. This helps extract all the grounds at the same rate which leads to more well-rounded taste without harsh bitterness or excessive acidity.
Things especially go wrong at both ends of the size distribution. Some grinders produce a lot of ‘fines’. These are basically coffee dust. Fines clog up the filter and therefore reduce the flow rate dramatically. Because the flow rate is slow, you might adjust the grind a bit coarser, now all the other grounds are too coarse so they aren’t extracted properly. Because the fines are extracted really quickly, they also give a very harsh bitterness to the espresso.
On the other hand you have ‘boulders’ or coffee particles that are much larger than the average. These will not extract fast enough and leave air pockets around it. Those air pockets will provide no resistance to the grounds.
A good grinder is a must so you get very little fines, very little boulders and a tight size distribution. Grinders for espresso and different styles of coffee aren’t necessarily the same so make sure your grinder can grind for espresso.
Check your coffee grounds after grinding (or taking a scoop out of the bag) for consistency. Is there a lot of dust? A lot of different sized particles? If so, it is probably time for a new grinder.
Before tamping, how you prepare the ground coffee in the filter is also important. Ideally you want the grounds to be distribute grounds as evenly as possible in the basket without any clumps. A dosing funnel helps you get all the grounds in the basket without a mess and a distribution tool helps break up clumps and distribute the grounds.
When the grounds are not distributed evenly, the density of the puck will be more or less in certain places. The water will flow faster through the less dense areas and slower through the denser parts. But since water takes the path of least resistance, most water will flow through the less dense parts. This is also bad for taste since the less dense parts will be over extracted.
After distributing the grounds in the basket, it’s important to tamp the grounds. This basically means compressing all the coffee particles together and getting all the air pockets out of the puck.
If the puck isn’t tamped hard enough, there are air pockets between the coffee particles which means there is less resistance and the espresso flows out faster. It also leads to the grounds not being extracted properly and the coffee being thin, watery and probably a little sour.
Most baristas use somewhere between 30 and 50 lbs. of pressure to tamp an espresso puck. You don’t exactly have to match that pressure but just go by feel. Once the puck stops compacting, that’s enough pressure and you can stop. There is no benefit to keeping pushing harder.
Not all baskets are created equal. There are open (naked) baskets and pressurized baskets. Open baskets create almost no resistance of their own so almost all the resistance comes from the puck. This means the grind size and puck prep is very important to get right.
Pressurized baskets only have one small hole in the bottom. That means the basket itself creates a lot of resistance. That means there is more room for error with grind size and puck prep without too big of an impact on the brew time as long as you don’t grind too fine. An open basket is considered better since there is much more control over the flow rate that isn’t impacted by the basket. Since the brew time is an indicator, getting a 30 second shot with a pressurized basket doesn’t really tell you anything.
The puck in the basket provides resistance. The pump in an espresso machine creates pressure that overcomes this resistance and pushes the water through the grounds.
Some machines have higher pressure pump which obviously would lead to a faster flow rate. Most espresso machines produce 7-9 bar of pressure at the group head. If your machine has a different pressure pump, it could lead to a different flow rate and faster or slower shot. 7-9 is optimal for taste though so if your machine makes much more pressure, that’s not necessarily a good thing.
Also, there are differences in how quickly the pressure is built after turning the pump on. Some machines build pressure faster than others and this obviously has an impact on the total shot length. This is why there is a range of time that is generally considered a good shot time. It also means you’ll have to experiment and learn how your machine works. Maybe your machine makes good espresso in a slightly different time frame than another machine.
Recommended Espresso Equipment
Besides an espresso machine, there are a few other tools that can make your espresso better. Here are my favorites:
- Espresso Machine: The Breville Barista Express (Amazon) is the sweet spot in price and quality for most casual home baristas. It comes with a built in grinder and most tools you need to brew espresso.
- Tamper: A nice tamper helps you tamp your grounds in the filter for the best result. Any correctly sized tamper can do the job but a nice heavy one just feels so much better in your hand than a plastic model. This Luxhaus one (Amazon) has a nice trick up it’s sleeve to make tamping very consistent.
- Beans: Good espresso starts with good beans. Using fresh beans is a big improvement over pre-ground coffee.
- Scales: Getting consistently good espresso means you have to know how much grounds is going into the machine and how much is coming out and how long this takes. A coffee scale is going to make your espresso much more consistent and also makes adjustments a lot easier. The Apexstone coffee scale (Amazon) is cheap and doesn’t look too sleek but is just as accurate as more expensive scales. The TimeMore scales (Amazon) look and feel a lot nicer but cost a bit more.
- Grinder: To make the best of your fresh beans, a good grinder is necessary. Espresso requires a good grinder to get the best results. The Baratza Sette 30 (Amazon) is a good espresso grinder that can also be used for other brewing methods and while not cheap, is good value for money. If you prefer hand grinders, the 1ZPresso JX-PRO is one of the best options (Amazon)
- Distribution tool: After grinding you can get some clumps in the coffee grounds. Those clumps should be broken up so the water can extract all the coffee grounds equally. Distribution tools are very simple things but this one (Amazon) is beautifully made and will look good in your kitchen.