Why-Does-My-Coffee-Taste-Bitter The Wood Roaster
Suzanne Rutherford

What is Making My Coffee Taste Bitter or Sour?

Ever brewed a cup of coffee at home and thought, "Why does this taste off?"

You’re not the only one.

One of the most common complaints we hear from home brewers is that their coffee tastes too bitter or sometimes too sour. The good news? It’s usually an easy fix, and it all comes down to a few simple brewing tweaks.

Let’s break it down.

Bitter Coffee? Here's Why

If your coffee tastes bitter, it's likely over-extracted. That means you’re pulling too much from the coffee grounds. You’re getting the good stuff, but also the harsh, unwanted compounds that lead to bitterness.

Potential Problems and How to Fix Bitter Coffee:

Grind Size: Your grind setting is too fine, leading to a slower brew time and over-extraction.
Solution: Adjust the grinder to a coarser setting, allowing for a faster extraction. Reducing the brew time can help mitigate bitterness 

Water temperature: If your water temperature is too high, it will contribute to over-extraction.
Solution: If your machine has a PID controller, we recommend between 92-94 degrees

Freshness of beans: Stale coffee will extract faster, leading to bitterness 
Solution: Buy fresh beans in smaller quantities 

Machine cleanliness: Old coffee oils and residue build up in the machine and portafilter, contributing to a bitter taste. 
Solution: regularly clean your machine, portafilter and basket. Purge the group head after each shot to expel any coffee grounds and oils. 

Other factors: 
Dose: Ensure you’re using the correct amount of coffee for your portafilter basket 
Tamping: Ensure an even and level tamp for a consistent extraction 
Water quality: Filtered water is important to remove any minerals that may contribute to bitterness and off-flavours. Filtered water is often overlooked and is one of the most important factors in making a tasty coffee. 

Sour Coffee? Here's What’s Happening

If your coffee tastes sour or a little too sharp, it’s likely under-extracted. You’re not pulling enough of the flavour out of the beans, which results in a weak and tangy cup.

How to Fix Sour Coffee:

Use a finer grind size
This allows the water to extract more flavour from the grounds.

Increase your brew time
More time helps draw out the sweetness and body.

Use slightly hotter water
Around 95 to 96°C is a good place to start.

A Few Extra Tips for a Better Brew

Use fresh, filtered water
It makes a huge difference to the final taste. Shop our water filter range.

Grind fresh, just before you brew
Pre-ground coffee loses its flavour quickly. Shop coffee grinders.

Use high-quality, freshly roasted beans
Like ours, of course. Fresh specialty coffee is best.

Not Sure Where to Start?

We get it. Brewing great coffee at home can feel a bit overwhelming. That’s why we created a quick coffee quiz to help you find your perfect match based on your taste preferences and brewing method.

Take the Quiz and discover your next favourite coffee.


Have questions? Our roasting team is always happy to help. Send us a message or drop by the roastery for a chat and a cup.

Happy brewing.