Why Is My Coffee Bitter? – Barista-Approved Tips

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We all love coffee, but it can be hard to enjoy the delicious taste if our brew is too bitter. If you feel irked by your cup of joe because it tastes so bitter, this blog post will help! 

Why is my coffee bitter? There are many reasons why your coffee may have a bitter taste that you should rule out before changing how long or what type of beans you use. 

We’ll go over some common causes and provide tips on how to fix them in the future! So read on for some advice on getting rid of bitterness from your morning cup!

Why Is My Coffee Bitter?

There seem to be multiple factors that make your drink bitter. In this section, we will explore what causes bitter coffee.

Over Extraction

When we brew coffee, the flavor depends on how well it has been extracted. The total amount of dissolvable solids and the evenness of extraction will define the quality of your espresso.

The secret to making an excellent cup of joe is all in the balance between the amount of water and ground coffee used. Water dissolves around 28% of the mass of a coffee bean. 

The remainder is made up of cellulose and plant fibers. Just add up some more water; the magic of turning coffee beans into a favorite drink will be done.

During the brewing process, the coffee bean has different flavors at different stages, but not all of them have desirable traits! What we’re aiming for as coffee lovers is only the good flavors.

Too little flavors from the bean or not enough water mean that you will get sour, under-extracted coffee. On the other hand, adding too much water can make even bitter and over-extracted brews, leaking bitter-tasting compounds into the water! As such, our recommendation is a 1:2-ratio between coffee and water.

Read more: Why does my coffee taste burnt

Wrong Grind Size

Grinding coffee beans alters how flavor components dissolve. If it’s too coarsely ground, the chances are that you risk under-extraction and, as a result, a flat or sour-tasting coffee. Nonetheless, if they are too finely ground, the coffee will be over-extracted and harsh.

Different brewing methods necessitate different grinds, and you may have to experiment to determine the sweet spot. In case you get a bitter cup, the grounds are likely too finely powdered. The flavor of your espresso will be substantially altered if you use a grind setting that is too coarse or too fine.

Under-extraction occurs when espresso pours too quickly. Slower espresso has a stronger flavor since the coffee solids take more time to dissolve – but only part. Your espresso will taste bitter if the shot is poured too slowly because the grind is too fine. As such, the coffee grounds need coarser to help the water flow more freely.

The average time for espresso to pour is around 25-35 seconds, with the perfect time found between 27-33 seconds.

Dirty Machine & Equipment

Drinking coffee with dirty equipment can cause bad tasting, so be sure to keep your machine clean for optimal results.

It’s a well-known fact that the coffee you enjoy will go rancid if you don’t get rid of oil residue from the machine through regular cleaning. Bitter, metallic, or astringent flavors in the drink may be attributed to baristas or beans, but oftentimes, these types of flavorings come from dirty equipment.

People often think that a coffee machine that doesn’t get used often will not build up oil as much as a high-volume machine. Still, that is simply not the case. The matter is related to the increased idling time. No water flows through them over time, which means they’re likely to accumulate oil quickly.

When the group head assembly and net showers get clogged with the coffee oils, it causes the water flow to be restricted. This results in uneven extraction and channeling. This not only causes bitter-tasting coffee but also puts stress on some parts of the machine, like the pump and the solenoid.

Too Long Steeping

It’s easy to overcook your coffee, and you might not even know it. Coffee, like tea, gains taste by steeping in hot water. If you let your coffee sit too long, then bitterness will set in. You don’t want burnt flavors ruining what could have otherwise been an enjoyable brew, do you?

This is a common mistake when making French press coffee since people tend to leave their coffee in the French press after pushing down the plunger. In such cases, the coffee continues to be extracted, and the following cup will undoubtedly be more bitter than the previous.

If you prefer to drink coffee leisurely, pour it into a thermal carafe and keep it hot.

Too Hot Water

When it comes to making coffee, the temperature is very important. If you want a strong brew with rich flavors and aroma, the ideal range for optimal extraction would be between 195-205 degrees F.

The water will boil at 212° Fahrenheit, so be careful not to let it overboil. Let the hot liquid sit just a minute before you pour over your coffee grounds.

Too Much Coffee Add-In 

Not only will adding too much coffee to the amount of water make your drink taste bitter, but in many cases, it can also cause nausea and vomiting.

Use Bad-Quality Coffee

You know that old adage about cheap coffee. It’s always worth repeating because it’s so true: you get what you pay for. The problem with cheap coffee is they’re over-roasted to hide imperfections caused by growing at lower altitudes and mass harvesting, which turns out bitter-tasting instead of sweet like the beans should taste!

Use Old, Stale Coffee Beans

Another factor that affects the taste of your coffee is age. Coffee doesn’t stay fresh forever, but do you know old beans can actually add a bitter taste to your cups?

There are several points at which beans start to “go bad.” If you’ve been used to the flavor of exceptionally fresh coffee beans, you’ll notice the “off” or “stale” aroma they have – even before you brew with them. Though there are certain techniques to avoid this, there is no turning back once your beans have gone stale.

Roasted coffee beans seem to be a rare delicacy, but the process by which they’re made is quite simple. Once roasted and ground into powder form, it only takes hours for certain aspects of flavor, such as oxidation or CO2 depletion, to start affecting taste significantly. This brings about what we know as “staleness” quickly after roasting!

Use The Incorrect Water Ratio

The ratio of water to coffee in your brew is also very important for flavor. Strictly speaking, it’s coffee strength that’s affected here. The more coffee you put in the same amount of water, the stronger it will be.

The ratio of coffee to water in your brew has a big effect on its flavor. The more coffee used in the same water amount, the stronger the taste will be. That’s not always true, as there will be more caffeine in a stronger coffee, and caffeine might have a bitter flavor.

The National Coffee Association says that a “golden ratio” of 1-2 tablespoons of coffee for every six ounces of water is the ideal amount.

The Coffee Itself

It’s also important to mention the coffee itself. Individual cultivars will have distinct flavors, and differing roast characteristics will have an impact on those as well.

There are two basic coffee varieties, Arabica and Robusta. Robusta has a stronger taste, so if you make coffee with a high proportion of Robusta beans to water, you will get a bitter brew.

Still, it’s probably not good. Robusta coffee may be bitter, but it’s worth the experience. In Vietnam, for example, condensed milk balances out this bitterness to make a delicious cup of joe!

How To Fix Bitter Coffee?

The above information must have solved your inquiry of “why is coffee bitter?”. Now, let’s see what we can do about it.

The coffee beans that you buy at your local grocery store or farmers’ market are a natural agricultural product, which means they’re not made in the factory somewhere. You might notice slight variations from bag to bag. 

Even if you make your coffee the same way, every bag will taste a little bit differently. This is totally normal and shouldn’t affect how delicious each individual cup of joe tastes – it’s just how fresh coffee works!

To fix bitter coffee, make sure that you just make a small adjustment so that it can taste balanced again. Remember: bitter = over-extracted; this means less extraction is what we want!

Below are four ways for you to extract less at home:

Grind Your Beans More Coarsely (Intermediate)

Larger grounds will extract slower, and water will drain more easily in pour-over brewing. This should shorten your total brew time in a few seconds!

Cut Down The Brewing Time (Easy)

There are a few different ways this can happen. If you’re working with an immersion brewer, such as a french press, you only need to press down the filter about 20 seconds earlier. As for pour-over brewing, you should pour in water faster or use a coarser grind for water to drain quickly.

Let Your Water Cool A Bit (Easy)

As mentioned above, water boils between 205-212 degrees Fahrenheit at low elevations, which is too hot for your coffee grounds. Allow it to cool for 1-2 minutes, and see what happens!

Use A Little Less Water (Harder)

Less water means each coffee ground will not have as much access to freshwater. If you use a pour-over cone, cutting down water will also reduce the brewing time because it will take less time to pour your water.

Caution: Only try one of these remedies at a time, and make small changes. You don’t want to go too far the other way and end up with under-extracted coffee.

It may take 2-3 tweaks to re-find the balanced sweet spot, but as you become more experienced with the technique, it will take fewer tries. Pay attention to your taste senses; they will lead you in the right direction.

Frequently Asked Questions

How To Know Without A Doubt That Your Coffee Is Bitter?

Our taste buds are like little scientists in disguise. They can determine pleasant-tasting food and warn us if we’ve consumed something possibly hazardous.

The human tongue can distinguish five flavor categories:

  • Sweet
  • Bitter
  • Sour
  • Salty
  • Umami

Most people notice bitter notes in the center and back of the tongue. If you detect a weird, unpleasant flavor there, it means your coffee is bitter.

Which Coffee Beans Make Less Bitter Coffee?

Arabica beans produce less bitter coffee than Robusta beans. Although the former is more expensive, you can create coffee with less bitterness and more flavor. You can also use beans from the Kona region, Costa Rica, or Brazil to make a less bitter cup.

Can Salt Make Your Coffee Less Bitter?

Yes, adding salt to your coffee can make it less bitter. Compared to sugar, salt is a better bitterness neutralizer. Thanks to its key component – sodium, salt can help block bitterness and enhance the flavor of your coffee.

This is due to the taste buds’ response to salty flavor over bitterness. Therefore, salt may work better than sugar at masking coffee’s bitterness. Sugar only masks it a little, but salt completely eliminates it.

Salt tastes pleasant because receptors on the tongue pick it up. It inhibits bitter and sour flavors, which explains why it is frequently used to make meals more delicious.

Do Light Roast Beans Make Less Bitter Coffee?

Yes, light roast coffee beans are less bitter. Coffee beverages created with light roasts have more caffeine and a brighter flavor than those made with dark roasts.

Final Thoughts

Why is my coffee bitter? It turns out that your taste buds and the coffee beans themselves have a lot to do with how bitter or sweet it is. So next time you find yourself reaching for another cup, take a moment to think about what might be making it so different from last week’s brew. Also, our blog post concludes by suggesting some things you can try if you are experiencing bitterness in your coffee.

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Almost 20 years already spent committed to coffee and more than 3 years of experience as a barista at Starbucks. Madelyn Doyle graduated with a Bachelor’s Degree in Nutritional Science from the University of California and finished the Coffee Skills Program at the Specialty Coffee Association (SCA).