Why Is My Espresso Shot So Bitter? (7 Common Reasons & Fixes)
Last updated on March 13th, 2025 at 04:31 pm
Why does my espresso taste so bitter? Yeah, I’ve been there!
When I first got my Breville Barista Express, I was beyond excited. It’s an amazing machine, and I was ready to pull café-quality shots at home.
But my first few espressos? Bitter. Really bitter. And I couldn’t figure out why. My beans were fresh, I was grinding them properly. At least, I thought I was. But something was definitely off.
I tweaked everything: grind size, dose, extraction time, even water temperature.
Turns out, there are quite a few things that can go wrong and lead to an overly bitter espresso. If this sounds familiar, don’t worry—you’re not alone.
In this guide, we’ll go through the 7 most common reasons espresso turns out bitter and, more importantly, how to fix it. So let’s start brewing!
Quick Table: Espresso Biterness Fixes
| Problem | Solution |
|---|---|
| 1 – Over-Extraction | Grind slightly coarser, reduce extraction time to 25-30 seconds, lower brewing temperature to 195-205°F. |
| 2 – Grind Size is Too Fine | Grind slightly coarser to avoid slow extraction and bitterness. Aim for a texture similar to table salt. |
| 3 – Too Much Coffee (Overdosing the Portafilter) | Use 18-20g of coffee for a double shot and evenly distribute before tamping. |
| 4 – Low-Quality or Stale Beans | Use freshly roasted, high-quality beans (within 2-4 weeks of roasting) and store them in an airtight container. |
| 5 – Incorrect Water Temperature | Set your machine’s water temperature between 195-205°F. Let the water cool slightly before brewing if using a manual machine. |
| 6 – Poor Machine Maintenance (Dirty Equipment) | Backflush your machine regularly with espresso cleaner and clean portafilters and baskets daily. |
| 7 – Using Too Much Pressure When Tamping | Tamp with firm but even pressure (around 30 lbs.). Avoid excessive force to maintain consistent water flow. |
Note: If you want more details on each issue, be sure to read the full guide!
7 Common Reasons Your Espresso Tastes Bitter (And How to Fix It)
Usually, bitter espresso is an easy fix. So, let’s talk about the most common reasons:
1 – Over-Extraction
Ever taken a sip of espresso and felt like you were chewing on a charred piece of wood? That’s because of over-extraction.
This happens when water takes too much time pulling flavors from the coffee grounds, dragging out all the bitter compounds. Instead of a bold, rich shot, you get one that’s dry, harsh, and just plain unpleasant.
How to fix it:
Grind slightly coarser. A super-fine grind slows the water down too much, which leads to over-extraction. You want to try loosening it up a bit.
Shorten your shot time. If your espresso is running past 35 seconds, it’s over-extracting. You want to aim for a sweet spot of 25-30 seconds.
Lower the brewing temperature. Water that’s too hot (above 205°F) pulls out extra bitterness. So, keeping it between 195-205°F helps tone things down.
2 – Grind Size is Too Fine
If your espresso is coming out like liquid tar and tastes way too bitter, your grind size might be the issue. A grind that’s too fine means water has a harder time flowing through the coffee puck. This leads to over-extraction, which pulls out all the bitter compounds you don’t want.
You’ll know your grind is too fine if your shot takes forever to pull (think 40+ seconds) or if the coffee drips out sluggishly instead of flowing smoothly.
While a fine grind is necessary for espresso, there’s a sweet spot: too fine and you’ll end up with a shot that’s harsh and unpleasant.
How to Fix It:
Grind slightly coarser – Try making small adjustments rather than going too coarse all at once. You want a texture similar to fine table salt and not powdered sugar.
Pay attention to shot time – A properly extracted shot should take 25-30 seconds. If yours is creeping past that, adjust the grind coarser until you hit that range.
Check your espresso puck – After brewing, tap the coffee out. If it looks like mud or leaves a soupy mess in the portafilter, the grind is probably too fine. Usually, a drier, firm puck means you’re in the right range.
3 – Too Much Coffee (Overdosing the Portafilter)
It’s tempting to think that packing more coffee into your portafilter will give you a stronger, richer shot. However, more isn’t always better.
In fact, overfilling your portafilter can choke your espresso machine, making the shot take way too long to pull. This means the water is stuck in the coffee bed for too long, leading to—you guessed it—bitter, over-extracted espresso.
If your shot runs past 35-40 seconds or barely drips out, you might be using too much coffee. Another clue? A soggy, sludgy puck after brewing instead of a firm, dry one.
How to Fix It:
Use the right dose – For a double shot, stick to 18-20g of coffee. Going beyond this (especially in smaller baskets) creates too much resistance.
Even out your coffee bed – Before tamping, make sure the grounds are evenly distributed. Uneven distribution means some areas get over-extracted while others stay under-extracted, leading to unbalanced flavors.
Check your headspace – When you lock in your portafilter, there should be a slight gap between the coffee and the shower screen. If the puck is pressed against the screen, you’re using too much coffee.
4 – Low-Quality or Stale Beans
Bad coffee beans are a one-way ticket to bitter espresso. I mean no matter how perfect your grind size, tamping, or extraction time is. If your espresso tastes dull, harsh, or just “off,” your beans might be the problem.
The fact is coffee loses its freshness fast especially once it’s ground. Even whole beans start staling after 2-4 weeks post-roast.
And if you’re using pre-ground coffee? You’re missing out on all the delicate aromas and sweetness that make espresso taste great.
How to Fix It:
Use freshly roasted beans – You want beans roasted within the last 2-4 weeks. So, check the roast date, not the expiration date!
Store them properly – Keep your beans in an airtight container, away from light, heat, and moisture. A sealed bag in the pantry works, but a vacuum-sealed canister is even better.
Grind fresh – If possible, grind your beans right before brewing. A good burr grinder can make a massive difference in flavor and extraction quality.
Skip the bargain beans – Cheap, low-quality coffee is often over-roasted to hide imperfections, which leads to excessive bitterness. Splurge a little on specialty-grade beans, and your espresso will thank you.
5 – Incorrect Water Temperature
Usually, water temperature is one of the most overlooked factors. It might seem like a small detail. However, brewing too hot can ruin an otherwise perfect shot.
The thing is hotter water extracts more solubles from the coffee grounds. That’s good to a point.
But go beyond 205°F (96°C), and you start pulling out harsh, bitter compounds that overwhelm the natural sweetness and balance of the espresso.
Instead of a rich, smooth shot, you end up with something that tastes burnt and overly sharp.
On the flip side, if the water is too cool (<195°F or 90°C), you’ll get under-extraction. In other words, a sour, weak espresso.
How to Fix It:
Set your machine to 195-205°F – Most espresso machines with temperature control allow you to adjust this. The sweet spot for most beans is around 200°F (93°C).
Let your machine fully heat up – If your espresso machine doesn’t have a PID (a precise temperature control system), give it at least 15 minutes to warm up before pulling a shot. You can run a blank shot (just hot water), which can help stabilize the temperature.
Manually adjust with a cooling trick – If you have a manual espresso machine or a basic model with no temp control, try this: lift the portafilter and let the machine “breathe” for 10-15 seconds before brewing. This helps slightly lower the temperature.
6 – Poor Machine Maintenance (Dirty Equipment)
But if your shots have an unexpected bitterness, your machine might be the issue.
Over time, coffee oils and residue build up in the group head, portafilter, and basket, creating a rancid, burnt taste that sneaks into every shot.
Even if your beans, grind size, and brewing time are all spot on, a dirty machine will ruin the flavor. Think of it like cooking with a greasy pan.
No matter how fresh your ingredients are, that lingering residue will mess up the taste.
If your espresso suddenly tastes more bitter than usual and you haven’t cleaned your machine in a while, it’s time for a deep clean.
How to Fix It:
Backflush your machine regularly – If your machine has a three-way solenoid valve, use an espresso cleaner like Cafiza once a week to flush out old coffee oils and buildup.
Clean the portafilter and basket daily – A quick rinse isn’t enough! Scrub them with hot water and a brush to remove stuck coffee particles.
Wipe down the group head – After each shot, run hot water through the group head and wipe it with a clean cloth. This prevents coffee grounds from sticking and turning rancid.
Descale when needed – Hard water buildup can mess with your machine’s performance and temperature stability. If you notice your espresso tasting bitter and flat, a good descaling session might be overdue.
7 – Using Too Much Pressure When Tamping
Ever feel like you need to crush the coffee puck into the portafilter to get a good shot? Yeah, been there. But here’s the thing: too much tamping pressure can actually make your espresso bitter.
When you tamp too hard, you overly compact the coffee grounds, making it difficult for water to flow through evenly. This can cause over-extraction, where the water lingers too long in the coffee bed, pulling out those unpleasant, bitter flavors.
Plus, excessive tamping can lead to channeling, where water finds cracks in the puck and rushes through unevenly. This results in a weak, bitter, or just plain weird-tasting shot.
How to Fix It:
Use even, firm pressure – You want about 30 pounds of pressure when tamping. If that sounds too technical, just press down firmly enough to compact the grounds but not so hard that you’re straining your wrist.
Keep it consistent – The key to good espresso is repeatability. Try using a calibrated tamper that helps apply the same pressure every time.
Check your puck after tamping – It should be flat and even, with no visible gaps or cracks. If it looks uneven, try distributing the coffee more evenly before tamping.
How to Make Your Espresso Less Bitter (Final Fixes)
At this point, you’ve fine-tuned your grind, tamp, water temperature, and extraction time. But maybe your espresso still tastes a little too bitter.
Well, there are a few more tricks to smooth out the flavor. For instance:
1 – Use a Lighter Roast Coffee
If you’re using a dark roast, that could be a big reason your espresso tastes bitter.
- Darker roasts tend to have more roasty, smoky, and sometimes even burnt flavors, which can make the bitterness more pronounced.
So, switching to a medium or light roast can bring out more natural sweetness and brightness in your espresso. Light roasts, in particular, have more acidity and fruitiness, which helps balance out bitterness.
2 – Adjust Your Espresso Recipe
Sometimes, small tweaks can make a huge difference. If your espresso is too bitter, try:
- Reducing the dose slightly – If you’re using 20g of coffee, try 18g and see if it improves extraction.
- Grinding just a bit coarser – A slightly coarser grind speeds up the flow and reduces over-extraction.
- Adjusting the extraction time – Keep it between 25-30 seconds for the best balance of flavors.
3 – Add Milk or Sugar for a Smoother Taste
There’s nothing wrong with adding a little milk or sugar if you prefer a milder and smoother espresso.
The reason is milk’s natural sweetness helps cut down the bitterness, while sugar rounds out harsher notes. If you don’t want regular sugar, try a tiny pinch of salt. I know it sounds weird, but it neutralizes bitterness without making your espresso salty.
Last Thoughts
Now, I’d love to hear from you! Have you struggled with bitter espresso before? What’s the best trick you’ve found to make your shots taste better? Drop your questions, tips, or even espresso fails in the comments, and with that voilà!
