Why Is My Coffee Bitter?

Most people who don't like coffee say it's because it's too bitter. While all coffee is bitter to some degree, it should not be the first flavor you get. So, if your coffee is extremely bitter, it usually means the beans are old, or it isn't being brewed correctly. Let's look at why coffee is bitter and how to make coffee taste less bitter.

Should Coffee Taste Bitter?

All coffee has a range of flavors, including bitterness. But that bitterness should never overwhelm or dominate the flavor of the coffee. While some coffees are more bitter than others, they should always have a relatively balanced flavor.

Fresh, high-quality coffee should have a balance of flavors, including acidity, sweetness, and bitterness. You should also taste other flavors depending on the origin of the bean, how it was grown, the level of roast, the grind, and how you brew it.

Bitterness in coffee is often the result of overly dark or burnt beans, using a high coffee-to-water ratio, and over-extraction during brewing. If your coffee is too bitter, you might need to change your grind size, brewing time, or water temperature.  

What Kind Of Coffee Is The Most Bitter?

When it comes to bitter flavors in coffee, you need to think about the beans and the brewing method. Both will impact the overall flavor of each cup of coffee.

Generally speaking, darker roast coffees are the most bitter. The roasting process caramelizes the sugars in the coffee. This creates caramel and chocolate flavors, but it also accentuates compounds that create bitter tastes.

As beans go stale, many of the flavor compounds fade. However, bitterness fades much more slowly. The result is that old coffee beans will always taste more bitter than fresh.

Preground coffee goes stale four times faster than whole beans. By the time you buy pre-ground coffee at the grocery store, it is almost always stale. It's almost impossible to brew a delicious coffee this way.

The other main cause of bitterness in coffee is the brewing method. Moka pot, espresso, and Turkish coffees are much more bitter than cold brew, French press, or even drip coffee. 

But you can also make coffee more bitter by brewing it incorrectly. Whether you make Chemex, pour-over, or AeroPress, every method needs a specific grind size, brew time, and water temperature.

Over-grinding the beans, letting it brew too long, or using water that is too hot is going to make your coffee more bitter. This is caused by over-extraction.

Extraction is the process where the hot water pulls flavors out of the coffee bean. Using boiling water pulls too much flavor out of the coffee, making it harsh. And once your coffee is too bitter, it's really hard to soften the flavor.

Why Is Coffee Bitter?

Most coffee is too bitter because of something to do with the bean or the way you are brewing it. Maybe dark roasts from South America are not your thing. Or perhaps you are overgrinding the beans or using water that is too hot. 

But if you have tried a bunch of different coffees and it is always too bitter, it might mean you need to clean your pot better. Not to mention that preground beans almost always make coffee harsh and bitter.

Here are the most common reasons that your coffee tastes bitter:

Certain Roasts Are More Bitter Than Others

Some coffees are more bitter than others. This is usually related to the roast level. Most dark roast coffees are more bitter than lighter roasts.

It's also important to remember that not all dark, medium, or light roasts taste the same. The level of roast is just one factor in flavor development. The type of bean, process, origin, and soil will all influence how it tastes.

Also, the same coffee can taste different depending on how you brew it. For example, a particular dark roast might be too bitter for espresso but perfect for cold brew. With any coffee, you need to find the sweet spot for your palate.

Coffee Beans Or Grounds Are Old

One of the biggest causes of bitter coffee is old coffee beans or grounds. As the beans age, the flavors fade. This brings bitter compounds to the front of the flavor profile. 

Beans are at their peak freshness 2 to 3 weeks after roasting. And fresh roasted coffee will last about a month when stored properly. But the level of bitterness will increase relatively quickly as it goes stale.

Preground coffee is almost always more bitter than whole beans, regardless of the roast profile. This is because there is more surface area and the coffee oxidizes faster. The result is bitter-tasting coffee. 

Used The Wrong Grind Size

Another reason your coffee is too bitter is using the wrong grind size. Depending on how you brew your coffee, there is an ideal grind size for that method. 

Overgrinding the coffee gives it too much surface area. As it steeps, it over-extracts the flavors and creates a harsh and bitter brew. 

See my [coffee grind size chart](link to grind size article) for the right settings for the way you make coffee. 

Under grinding coffee will also impact the flavor, but not in the same way. Instead of too bitter, the coffee won't have a strong enough flavor.

Overheated The Brewing Water

Regardless of how you brew your coffee, you ideally want to use water that is between 195° and 205° F. For the rest of the world that is smart enough to use the metric system, that's 90.5° to 96° C.

Using water at the boiling point, 212° F or 100° C, causes overextraction. This pulls out more flavors, especially the harsh compounds that create bitter coffee.

If you are boiling water to make coffee, pull it off the boil and wait about 30 seconds before starting your pour. This allows the water to cool down enough that it maximizes flavor without becoming too bitter.

Brewed For Too Long A Time

All coffee is meant to be brewed for a specific time. Espresso shots are pulled in about 20 or 30 seconds. Pour-overs take 3 to 4 minutes. Even auto-drip machines are meant to brew in 4 to 6 minutes.

However, allowing the coffee to brew longer will extract more of those harsh and bitter flavors. No matter how you make coffee at home, set a timer to prevent overbrewing. 

Coffee Has Gone Stale In The Pot

Coffee will also get more bitter the longer it sits in the pot. Brewed coffee is best for 1 to 2 hours, but it will start going stale almost immediately. 

As it goes stale, the nuanced flavors will fade first, leaving the coffee burnt and bitter. The coffee also evaporates on the burner, making it stronger. 

Leaving it on the counter limits evaporation, but it will go stale faster as it cools down. And microwaving cold coffee will only make it more stale and bitter. 

Coffee Maker Is Dirty

Lastly, brewing releases all kinds of coffee oils and flavor compounds. These will build up if you don't clean your coffee maker or brew pot regularly. 

This coffee residue ages and becomes more concentrated with time. As a result, even a light roast coffee can taste overly bitter and harsh.

You should wash your coffee pot with soap and water every day and descale with vinegar once a week. 

How To Make Coffee Less Bitter

If you are having a hard time drinking coffee that is overly bitter, here are a few ways to make it more enjoyable.

• Add Salt - Salt?! Yes, salt. It's proven to cut bitterness better than milk or sugar. Just sprinkle in a pinch. Salt is also a great way to brighten up stale coffee in the pot.
• Add Fat - Fats like milk, cream, and butter will cut the bitterness in coffee. While they might not actually be fats, non-dairy creamer and milk-substitutes like oat, almond, and soy work basically the same. 
• Add Sugar - To a certain extent, sweet and bitter cancel each other out. So a teaspoon of sugar or any sugar substitute can make a bitter coffee more enjoyable. The same goes for any flavored coffee syrup.
• Add Cardamom, Cinnamon, Or Nutmeg - Grating some green cardamom, cinnamon, or nutmeg into your coffee can trick your taste buds into thinking it is less bitter. While you might think chocolate will work too, most powdered chocolates will actually make it even more bitter.
• Add Citrus - The acids in citrus fruits will cancel out bitterness. But squeezing a lemon, lime, or orange into your coffee is not the solution. Instead, grating a little citrus zest into a bitter cup of coffee will help balance it out.
• Freeze It - Really, I'm not joking. The cold dulls the flavor, making it less bitter. So if you have coffee that is always too bitter, brew it up and freeze it. Make a coffee granita or put it on top of your favorite ice cream or cake.

And if you can't find a way to make the coffee less bitter, pour it in your garden or flower bed. Coffee grounds are a great source of nitrogen that plants love.

Tired Of Bitter Coffee? Get Fresh Beans You Love From Cupa! 

The best way to avoid drinking overly bitter coffee is to get freshly roasted beans. Take a look at our selection of whole bean coffees in a variety of different roasts and origins. All of my roasts are available for wholesale coffee customers and many are a available in 5 pound bulk bags of coffee. If you have any questions, shoot me a message on Instagram. I’m happy to help you choose a coffee that you are guaranteed to love.