Making a proper espresso is rewarding, but it can be cumbersome when starting out. Like most things in life: when it’s good it’s great. However, it’s frustrating to put your time (and money) into it and pull a sour shot of espresso.
There is no device to tell you why it’s sour. Unless you’re a seasoned barista, it’s hard to know what caused the off taste. Some blame the espresso machine, grind size, water, etc.
Although these factors could be the culprit, the problem typically arises during the extraction process. Chances are you’re making some small mistakes costing you the taste of sweet success.
This article discusses why espresso tastes sour and how to fix it.
How to Tell if Your Espresso is Sour or Bitter
The difference between sour and bitter espresso is apparent once you understand the distinction.
Sour espresso has a bit of bite and is dry. It’s due to the tannic acid in the beans (learn about the science behind tannin in caffeine). It’s the same tannins in wine. After you swallow, you can still feel the dry & bitterness in your mouth.
Bitter espresso lingers on your tongue afterwards too. Bitter coffee lacks flavor and tastes stale. Think gas station coffee in the middle of nowhere at 4am.
Learn how to decipher what coffee companies are trying to say, so you can get the best kind for you!
What Causes Sour Espresso & How to Fix it
There are different reasons why espresso tastes sour. It could be because of the prep method, wrong ratio, etc.
Below are the most common reasons espresso tastes sour:
Poor Preparation Method
Espresso preparation technique matters.
Ex: Shots taste weird if you use a dirty portafilter. Also, you’ll get an under or over-diluted drink if you choose the wrong coffee to water ratio.
Here are other costly mistakes coffee lovers make:
- Ignoring good tamping practices
- Grinding straight into the portafilter without weighing
- Not measuring water
- Timing extraction in your head
If you’re guilty of these mistakes, and everyone does it at some point, you’re going to get a sour tasting shot.
Solution
Focus on the most important variables when brewing espresso: grind size, time, and ratio. We’ll discuss them here.
Also, follow the recommended process for brewing espresso.
Ex: Grind your coffee, then distribute your grounds evenly before tamping. You’ll notice an instant improvement in your shots.
Use the timer on your phone. Aim for 20-30 seconds. Timing starts from first drip to last drip.
Short Extraction Time
Many put too much emphasis on the ground’s coarseness and less attention to the more important aspect; extraction time. The time actually pulling the shot, which should be 20-30 seconds.
Pro Tip: If the shot is taking less or more time then check your grind, tamp and dosage. A good way to tell if your tamping unevenly is if the shots are pouring unevenly from a double spout.
Your shots will taste sour if you run your shots short. The bitterness will come from a heavy concentration of particulates in your basket.
Let me explain:
When you tamp the grounds, a small percentage of ground coffee particulates will go into your cup as water flows through the puck. Your small shots will have a higher concentration of bitter elements. You’ll get a sour drink with a bitter taste. Sometimes the bitterness can intensify the sourness.
Solution
Extend the pull time. If you use 10 grams in and you’re doing 20 grams out in 30 seconds, your coffee will be good if you run your shot a little longer. Water will flow evenly through for a more even extraction.
No problem! Click to learn how to make the delicious espresso drink without the need of expensive equipment.
Using The Wrong Ratio
The brew ratio is the amount of coffee you put inside the portafilter against the mass of the brew you get.
Ex: 20 grams of ground coffee should yield 40g of liquid espresso. Your shots will be sour if you use the wrong ratio, so stick to the standard 1:2 espresso ratio.
Solution
There’s no such thing as a perfect ratio. Too many variables from the water to the machine, and bean types, just to name a few.
It varies according to the roast profile, origin, etc. The 1:2 ratio is more like a guideline for brewing espresso. Start with it then adjust to 1:2.5 to 1:3 while keeping everything constant. Change 1 variable each time and then try again.
Pro Tip: If your portafilter is too big, there is no need to fill it up. If the basket is small, then dial it down and change all your measurements accordingly.
Take notes and test until you get the perfect ratio that delivers that hits your sweet spot.
Poor Water Flow
Water flow plays a key role in pulling an espresso shot. Water will move through the puck evenly if your grounds are ground finely, evenly and compact. If not then water will move through the same channels. This is called channeling.
A major culprit of sour shots is under extraction.
Note: You might be tempted to grind your coffee further or extend the extraction time. That’s a wrong move. Instead, check the water flow in the puck to see signs of channeling.
Solution
Coarsen your grind and allow a shorter time. The water will flow evenly through the puck. You’ll get a more even extraction and better results
Using The Wrong Beans
The roast level also determines if the coffee will turn out sweet or sour.
We don’t recommend light roast for brewing espresso. It’s difficult to extract, and shots are tough to achieve a balanced flavor profile.
Also, light roasts typically demand expensive machines and require experience.
Solution
We recommend using dark roasts for espresso.
Dark roasts are made for most espresso machines. They’re more forgiving for small variances to your dose, yield and extraction time. Therefore, you’ll get the best chance to pull off a great shot and avoid the dreaded sour espresso.
Fixing Sour Espresso is Tedious but not Impossible
If you love your espresso balanced, but keep getting sour shots, you’re doing something wrong. Fortunately, we’ve discussed why most espresso tastes sour and how to fix the problem.
By isolating and identifying the problem you can fix a sour espresso and get a truly great espresso.
