Why Does My Coffee Taste Sour? How To Fix It

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Imagine waking up one fine morning and looking forward to starting your day with your favorite cup of coffee only to wonder: why does my coffee taste sour? It is one of the worst feelings ever.

Why does my coffee taste sour? There could be a few reasons why.

1) You’re using old or stale beans. Make sure to buy fresh beans and grind them yourself just before brewing for the best flavor.

2) Your water is too acidic. If your water has a high acidity level, it can make coffee taste sour. Try using filtered or bottled water instead of tap water to see if that helps improve the taste.

In this article, we will tell you what makes your morning brew turn sour so that you can avoid them.


Why does my coffee taste sour?

Sour coffee is the worst thing that can happen to a good day. It’s gross. It’s not good for your energy levels to have coffee that tastes bitter.

Sour coffee isn’t something you have to live with.

We’ll show you how.


Sour coffee means bad beans or bad brewing

Coffee beans that are under roasted will taste bitter and grassy. They will taste sharp and lemony if they are old and stale. Click To Tweet

Chances are that your beans are fine but you may need to make some adjustments to the way you make your coffee.

why does my coffee taste sour


Sour coffee is often a result of under-extracted coffee grounds. This means that the beans were not brewed well enough so the flavors don’t balance out the acids during the brewing process.

Here’s what happens when beans are under-extracted and coffee tastes sour:

  • Beans were too coarsely ground. Fine grounds are easier to extract, but larger ones take longer because the water takes more time to reach the center of each particle. A too coarse grind size on blade grinders could mean that each particle is not getting the time it needs to extract the right amount of water.
  • Brew time is too short. Brew time should be long enough to bring out flavors and calm down acids. You might have pushed the filter down too soon with a French press. You might have poured your water too fast with a pour-over cone and it may have drained too fast.
  • Water is not hot enough. The ideal water temperature for brewing coffee is 195 to 205 degrees. It will not extract the best stuff from the coffee as quickly if it drops below that temperature, which can lead to under-extraction.
  • Water is not enough. The coffee-water ratio is very important. If you don’t give each bean the right amount of water to extract a balanced brew you will naturally end up with under-extracted coffee.

If you buy dark roast coffee at the grocery store, you will probably notice that specialty coffee beans taste more acidic than normal. This is by design. Some of the tang and zing are left to enhance other flavors.

Allow your taste buds to adjust. Sometimes it takes several cups before you realize the extra acidity helps bring out great flavors in super dark beans.


How to fix sour coffee the barista way

Each coffee bag is unique so it’s perfectly normal to make small adjustments when switching beans to get it to taste better.

Although one coffee may taste great, if you switch to another bean and follow the same steps, it might taste stale. That’s how fresh food works, so don’t worry!

why does my coffee taste sour


Remember that sour coffee is under-extracted coffee. The goal is to extract more.

Here’s how to increase extraction to fix your sour coffee, straight from professional baristas:

  • Grind your beans into a finer texture. It will take less time to extract balanced flavor from smaller grounds. This is true even if you do not change anything else. The brew time is also extended by smaller grounds that slow down the water draining in pour-over methods.
  • Increase brewing time. Add 20 more seconds to the brewing time if you are using an immersion brewer such as a French press. Pour-over coffee can be made by either slowing down the pouring of water or grinding your beans finer to slow down the draining.
  • Monitor the brewing temperature. Your water temperature should be between 195 and 205 degrees for optimal brewing. If you live in an area where the boiling point of water is lower, use it immediately so it doesn’t cool down.
  • Add more water. Make sure each bean has easy access to fresh water during extraction. More water also means longer brewing time for pour-over coffee.

Do not try more than one solution at a given time. Your changes should also be minimal. If you make too many changes, you might end up going too far in the opposite direction: over-extraction.

Sometimes, it takes just a few adjustments to get back to that sweet spot. It will take less time if you are more comfortable with tasting your coffee and making adjustments.



So, why does my coffee taste sour? There could be a few reasons — but the most common ones are using old or stale beans, having water that is too acidic, or grinding the beans to course. Experiment with different brewing methods and bean types to find what works best for you and produces the tastiest cup of coffee.

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