How To Tamp Espresso – Tamp Pressure and Common Mistakes

Tamping is one of the quickest parts of the espresso brewing process and, when done correctly, is a simple procedure. However, there are still factors to consider to ensure that your tamping technique and equipment are correct. What’s more, getting it wrong would be enough to ruin what would otherwise have been a delicious shot.

In this article, we will look at the correct methods for tamping and common mistakes to ensure that you adopt good tamping habits to provide the perfect coffee puck every time.

What’s Tamping Espresso For?

Tamping involves using a tamper to apply pressure to the bed of your ground coffee in your portafilter to remove air pockets and create a denser puck.

This creates more water resistance and more even control of water through the puck. The theory is that it helps ensure that the coffee is neither over nor under-extracted, providing a more flavourful shot of espresso. When tamping, you look for the correct balance of resistance and flow.

How To Tamp Espresso Like A Pro

Step One: Once your coffee grinds are in the portafilter, adjust your standing position. Hold the espresso tamper and try to keep your wrist straight and press your tamper against the bed.

Step Two: Begin to press the ground coffee, but don’t apply too much pressure on them. You only need to tamp for a few seconds. If you go in too hard, there is a chance you won’t be going in flat.

Step Three: Remove the tamper gently. If you remove the tamper too quickly, there is more chance of suction leading to the removal of some of the grounds.

How Hard To Tamp For Espresso?

There is no minimum or maximum tamping pressure. However, the consensus is that around 20 lbs to 30 lbs of pressure is ideal. If you tamp too hard, it will make the coffee puck too tight, which can plug the holes of your filter basket and stop water from leaving the puck.

There can be a physical cost, too, particularly if you are a professional barista making 100 or more cups of coffee a day – it can hurt your wrist.

Conversely, if you tamp too softly – under 15 lbs of pressure – water will quickly saturate the ground coffee and increase the flow rate, especially if your espresso machine has pre-infusion. This can cause channeling, leading to a watery and unsatisfactory espresso.

Does Tamp Pressure Really Matter?

While tamping is known to impact the shot quality, many experts have discovered that it doesn’t significantly change the flow rate and espresso extraction within certain parameters.

One intriguing experiment carried out by Lifestyle Lab used different tamp pressures and discovered that the flow rate and overall shot time were indeed almost unaffected by a decrease in tamping pressure from 35 lbs to 25 lbs [1].

However, there was a significant difference once that pressure dropped beneath 15 lbs. Nevertheless, without pre-infusion, the flow rate and shot time are relatively similar regardless of tamp pressure.

Another thing to note is that once tamping pressure reaches around 20 lbs and over, the flow rate and shot quality are relatively consistent with or without pre-infusion.

It’s not just Lifestyle Lab that has put this to the test. Seven Miles Coffee Roasters also researched the subject and found the same result:

“higher tamping pressure made no difference to the extraction.”

– Seven Miles Coffee Roaster – Tamping Coffee: does it even matter? [2]

Therefore, we can conclude that altering the grind size is the most effective option when your shot time is not correct when dialing in.

What If You Don’t Tamp At All?

Those results may make you wonder what happens if you don’t tamp. The answer is that it is not a good idea to avoid tamping.

If you do, your espresso will have lots of channeling and a fast flow rate. This will result in a sour and watery espresso because it will be severely under-extracted as the water will not have spent enough time interacting with the coffee. We tried that and the drink was not drinkable.

Another issue with failing to tamp is the mess it creates in the portafilter. Cleaning the mess after pulling the shots will likely take longer than simply tamping for a few seconds beforehand.

Level Tamping Is More Important

When tamping, one of the most important considerations is ensuring the grounds are level with the basket. Indeed, one test that applied the same tamping pressure across three shots, but used a level tamp on one, a 10-degree tamp on the second, and a 20-degree tamp on the third found considerable differences in the shot’s flow consistency.

There was also more channeling in the angled tamps, while those espressos did not taste as good.

Not only that, but the results were even more stark between 10 and 20 degrees, suggesting the results worsened the greater the angle. Therefore, it is vital to ensure you tamp level.

Should You Twist The Tamper After Tamping?

Many baristas twist at the end of their tamping, which helps polish the coffee bed to ensure a flat surface for more even extraction. While this could be a useful technique if you didn’t tamp level in the first place, it’s not necessary if you employ the correct technique beforehand.

Nevertheless, if twisting at the end of your tamping offers extra assurance that you have a flat tamp, there is no harm in the practice.

Common Mistakes When Tamping Coffee

Mistake 1: Tamper doesn’t fit the filter basket

If your tamper is the wrong size for the filter basket, it can lead to several problems, including the ability to apply the necessary pressure to avoid under-extraction. More likely is uneven tamping, which can lead to channeling and an uneven extraction.

There may also be a coffee waste if your tamper is not the right fit for the basket. The poorly fitting tamper will lead to coffee grounds being pressed out of the sides of the basket leading to wasted coffee.

Mistake 2: Tamp right after grinding without leveling the coffee bed

If you grind into the basket, then immediately begin tamping without leveling the coffee bed, after you tamp, the center of the coffee puck will be denser than the outer edges.

That will force the water to those edges before it can reach the center, causing uneven extraction.

Mistake 3: Not tamping on a level surface or level basket

Some portafilters have a spout and stay level when you place them on a table. However, with bottomless portafilters, you must ensure the basket is level before tamping.

Mistake 4: Tamping too hard

If you tamp too hard, while it is unlikely to affect the extraction quality, you could clog the filter basket or damage your wrist, particularly if you are a barista who pulls dozens of shots daily.

Mistake 5: Removing the portafilter too quickly

If you remove the portafilter too quickly. there is more chance of a suction effect that will bring some of the coffee with it, causing both wastage and the tamp to be less flat than ideal.

Mistake 6: Wrong wrist angle

Using the wrong wrist angle also increases the chances of damaging your wrist and more difficult to get a level bed. However, another potential issue is that the tamping pressure will not be even throughout, leading to uneven extraction.

Final Thoughts

Tamping need not be an infuriating or painful part of the espresso-pulling process. Indeed, it will be the opposite of those things when done correctly.

As we have explained, some extremely simple methods ensure you tamp correctly each time. The key is not to overcomplicate by applying unnecessary pressure or flourishes.

You only need to consider your consistency from shot to shot. If you master this, tamping is one of the most straightforward elements of pulling a great espresso shot.

FAQs

References:

[1] Espresso Tamping Pressure | Does it Matter?? – https://youtu.be/i70xWHhiFzI

[2] Tamping Coffee: does it even matter? – https://www.sevenmiles.com.au/blogs/editorial/tamping-coffee/