Why Coffee Tastes Sour, Bitter, or Burnt?

Coffee acquires sour taste if it is under-extracted. It means that the water ran through the coffee to quickly and didn't extract all the needed tasting oils from it. It is the result of coffee that was poured in during less than 15 seconds. This coffee color will be pale, the coffee itself will have acidic and tart smell, and coffee cream will dissipate rapidly.

Another reason of getting sour coffee is too coarse ground as it directly influences the amount of extraction the coffee gets.

To avoid it just make sure that you adjusted coffee grind to be finer. It reduces resistance and helps the water get through the coffee grind more evenly.

Too bitter coffee typically has a certain appearance: there are big patches of white foam in the floating oils in coffee. It is the result of over extracted coffee. Apart from too long brewing time, coffee bitterness may be caused by other factors. Firstly, it can be temperature when water is too hot. Another reasons are grinds, which are too small, and ratio: too much coffee in comparison with the amount of water.

Here you can learn more about bitterness in coffee and reasons why coffee tastes this way.

Remedy: carefully control brewing time of your espresso. It is recommended to do it for nearly 25-35 seconds. Keep watch on the shot as it comes through and when you see the coffee coming out in a light color, stop immediately. One more advice is to adjust grind size to a more coarse one. Too fine grind will make your coffee pour out much slower, this, in turn, over extracts coffee and makes it bitter.

Burnt coffee has a very dark color pouring out. Even after a long extraction time, you will get a small amount of coffee. It heats up much faster and acquires burnt and harsh taste. Most probably, the coffee grind is too fine, you might be tamping it too firmly, or there is too much coffee in the basket.
Remedy: control water temperature and ensure that it is not boiling, just hot (about 95C).

There are many reasons for it. It may be low quality coffee beans or water, dirty equipment, or even any leftover coffee that was left in the pot.
Just take into consideration all of the factors mentioned above to avoid unpleasant and harsh coffee taste.


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