Coffee tasting bitter or sour? Here's a troubleshoot guide

Troubleshoot guide


Coffee tasting too bitter or too sour ?

There are many variables that are adjustable when brewing coffee and all of them inevitably have an impact on how your coffee is going to taste.

We give a really basic and quick guide on how to fix your brew if something isn't quite right, understanding extraction is an integral part of improving your coffee skills.


Acidity in coffee isn’t always a bad thing, Kenyan single origins, for example, are known and highly sought-after for its wonderful,  and very intense acidity.

Acidity helps the coffee shine through milk based drinks like cappuccinos and make for vibrant and bright coffees.

 For acidity to taste good in your cup, it needs to be really well balanced with some sweetness and also some bitterness. Try not to confuse the presence of well-balanced acidity for unwanted sourness. If your coffee tastes extremely sour it means that the coffee is under extracted.

Something to also keep in mind is that acidity is more prominent in lighter roasts compared to darker roast.


Bitterness is normally associated with coffee so it’s easier to explain the good side of bitter notes in your coffee compared to explaining much needed acidity.

You will probably immediately pick up if something is wrong in your cup if it tastes way too bitter, almost like burnt rubber.
This simply means that your coffee is over extracted. Think about the flavor of REALLY dark chocolate or burnt onions.

The coffee brewing or extraction process will start by developing acidic and sour notes, progress towards bitter notes and then the bitter notes become overwhelming and unpleasant burnt rubber.
Finding the sweet spot between the peak of the acidity and the peak of the bitterness is key to a balanced and tasty coffee.

Try adjusting the following variable, adjusting one at a time so you know where the problem lies.


 Grind size

Brew time

Water temp



Increase ↑



More coarse




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