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If why is my coffee sour appears in your Google search bar, then keep reading.
There are two kinds of people; those who love coffee and those who can’t stand it. Chances are if you’re the latter it’s because you think “this is too bitter!” or “this is too sour!”. Well, good news friends, you could very well be right. Since I started experimenting with different manual brewing techniques using fresh roasted coffee, I’ve found that my same flavor of coffee can taste different based on the method I brew. I often ask myself “why is my coffee so sour?” because I never really taste the bitterness in coffee, but turns out, there is a reason why both of these are true.
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A Crash Course in Coffee
I won’t get into the nitty gritty of coffee chemistry, but it is something we probably should chat about; later. But for today, the one thing I want you to take away is that coffee can be both bitter and sour and neither should be the case. Ever. That’s if you’ve brewed it right. Arabica beans generally are more ‘fruity’ because of where they are grown and the majority of coffee is Arabica beans. If you’re a light or medium roast drinker, you are more than likely getting more fruity notes than chocolate or nutty and this is not only because of the bean, but also because of the roast. The longer a bean roasts, the more ‘fruity’ or sour compounds are released. It is possible to taste the fruit notes without it being sour because what you’re tasting is the actual flavor of the type of bean versus a mistake in brewing.
How we doin’? You still with me? Good.
Why is my coffee sour?
You’ve ground your beans, your water is proper temperature (195-205 degrees F) and you’re ready to infuse your beans. The first few drips of your coffee is going to be VERY fruity and sour. Why? Because those compounds are released first when the water engulfed the bean particles. If you were to stop your brewing and take a sip of the first drips, you would find it to be very sour. As the water continues to flow through the grinds, more flavor is extracted, deepening the profile and enhancing the taste. However, you could still end up with a sour cup even after your cup is done brewing. Your coffee is sour because the grind size of your beans are too coarse. There is too much surface area, allowing the water to run quickly through the grinds, generating a sour taste.
The Solution
It’s a simple solution really; adjust your grind size. This is why having your own grinder at home is helpful. YOU control the coarseness of the bean allowing you to experiment with different brewing methods. If you need help with selecting a grinder, read about the grinder I use and why I like it. In order to avoid sour tasting coffee so you don’t have to ask “why is my coffee sour?”, grind your beans a bit finer until you no longer taste sour notes. I have found that just about every roast is different. One roast might be perfect at grind size of 5, but then the next roast needs to be at a 7. If your auto drip is consistently producing sour coffee, then adjust your grind size to be finer.
Don’t forget to check out my home barista essentials where you’ll find all you need to create the coffee bar of your dreams! I’ve listed some of my most favorite coffee bar essentials and am sharing all of them so you can create great coffee house favorites right at home!
I have been loving my Rae Dunn “Drip” ceramic pour over! It produces one smooth cup of coffee! Follow me over on Facebook for more tips and tricks for manual brewing! Till next time…keep exploring!
Holy crap! I never knew this! Good info!
Pretty crazy huh!
Love it! As a former barista for 9+ years I love when people take the time to educate others on the proper way to brew a good cup of coffee! And it’s a good reminder for me of how to get my perfect cup!
Right?!? I love a good coffee shop coffee every once in a while but I love brewing manually at home too! Thanks for reading!
Monica, you are spot on! Now I don’t have issues with sour coffee. Actually, I didn’t know that coffee could be sour. My issues is always with bitter coffee. Hate bitter coffee. But, I’ve learned that sour coffee is sour for the exact opposite reasons that bitter coffee is bitter.
Just as you said, the main issue is often grinding, either too course or too fine. And you’re absolutely right it all depends. It depends on the kind of bean, the roast, how fresh the bean is, etc. And like you I have a Krups burr grinder that I’ve been using for years and years and years. My suggestion is to buy a used one on Amazon. You’ll save money and there’s still a lot of life in that grinder.
Hi Russell!
Honestly I didn’t even know you could buy a used grinder on Amazon! Thanks for the info! I’m with you; bitter coffee is terrible!