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Why You Should Put Eggshells in Coffee: Improved Flavor & Tips


Have you ever gone to take a sip out of your coffee and been taken aback by its bitter flavor? If so, might we suggest adding eggshells to your coffee? Although this may sound a bit odd, this trick is a great way to make your coffee more mellow.

Not to mention, this trick is straightforward to execute. It requires no expert knowledge about cooking or coffee. It is as simple as adding one extra ingredient to your coffee grounds. That’s it! To find out more about using eggshells in your coffee, read on.

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Why would you put eggshells in coffee?

There are two reasons why you would put eggshells in coffee. For most people, it is because eggshells make coffee taste less bitter. The other reason is that eggshells help to keep the coffee grounds down in cowboy or camping coffee. Let us take a closer look at both of these reasons.

Credit: Gheorghe Mindru, Shutterstock

Do eggshells make coffee taste better? Surprisingly, Yes!

The main reason people put eggshells in coffee is that it makes the coffee taste better and less bitter. Eggshells are made primarily of calcium carbonate. This is an alkaline material that can help balance out the taste of acidic coffee.

Coffee is by nature acidic. Although some coffees are more acidic than others, the acidity makes coffee taste a bit bitter. The more acidic the coffee is, the stronger or more bitter it tastes. Even though many people love strong coffee, not everyone can handle the bitter flavor.

When you add eggshells to coffee, it results in a less acidic and more mellow flavor. Admittedly, the coffee is much less complex tasting, but many people prefer the mellower flavor of eggshell coffee to complex and bitter coffee.divider 3

Eggshells in Cowboy Coffee

Another reason people use eggshells in coffee is that it helps to keep loose coffee grounds down. This won’t benefit modern coffee pots since the grounds are already separated, but it is incredibly useful if you cook coffee in a pot.

In addition to keeping the grounds down, campfire cowboy coffee is naturally robust and bitter. Since the grounds are directly in the boiling water, the acids create a powerful flavor. The added eggshells ensure that the taste is desirable, all while keeping the grounds down.

Cowboy Coffee Recipe
You don't have to be a cowboy to try this rough and tumble recipe! Cowboy coffee is one of the easiest, most basic coffee brewing methods -- and you can do it over an open fire.
Try this delicious recipe!
cowboy coffee on the campfire

How to Use Eggshells in Coffee

It is entirely useless to know you can add eggshells to your coffee without knowing how to use them. Let’s take a look at how to use your eggshells in the coffee, no matter what brewing method you prefer.

Getting Started

Before getting started with the recipe, you will need to gather the needed materials. The ingredient list is pretty short, and you likely have all of it already.

  • Coffee
  • Eggs (number depends on the amount of coffee you are making; approximately 1 egg for 4 cups)
  • Coffee pot or maker
  • Coffee scoop
  • 2 small bowls

The number of eggs you will need is determined by how much coffee you are brewing. If you are using a small pot, which would be about four cups of coffee or less, you only need one egg. It is helpful to have one egg per four cups. With this ratio, use two eggs if you are making 8 cups of coffee.

You can also add more or fewer eggs depending on the flavor profile once you get used to the recipe. Feel free to perfect the egg numbers based on your ideal cup of Joe.

Step 1: Crack the Eggs

To begin, you will need to crack the eggs before brewing the coffee. This is where the bowls come into play. Crack the egg into one bowl and place the shells into the other. This helps you to keep everything clean and organized, free of contaminants.

carton of eggs
Image Credit: Jakub Kapusnak, Unsplash

Step 2: Clean the Eggshells

Once you crack all the eggs, you need to clean the eggshells. Uncooked eggs can be incredibly dangerous to consume. Use hot water to rinse out the eggs thoroughly. Do not let any eggs remain inside the shells.

Step 3: Prep Your Coffee Machine

Next, it’s time to start making your coffee. Simply prepare your coffee machine or pot just as you usually would. This includes adding water and coffee grounds to the machine or bowl. The same goes if you are making coffee over a campfire. At this step, don’t turn on the coffee machine yet.

As you are prepping the coffee, use the correct proportions of coffee grounds to eggshells. If you use more coffee, the flavor will still be bitter simply because you don’t have enough eggshells.

Step 4: Add the Eggshells to the Coffee Grounds

Now, it is finally time to add the eggshells to your coffee grounds. Before adding them, crush them in your hands. The eggshells should be small enough to mix well with the grounds, but they should not be so small as to slip into the final product. Simply crushing them in your hands will suffice. Crush them in a paper towel if you don’t want your bare skin to touch the shells.

Once the eggshells are properly crushed, add them to the coffee grounds. In a coffee machine, simply place them in the container where the roast goes. If you are cooking it over the campfire, add the eggshells to the pot. No matter what your brewing method is, just put the eggshells where you put the coffee grounds.

cowboy coffee on the campfire
Image: Jarno Holappa, Shutterstock

Step 5: Brew as Normal

Here’s where the instructions get easy. Brew your coffee as normal. You don’t need to change anything about your brewing method from this step on.

Step 6: Enjoy Your Coffee!

Finally, you get to drink your coffee. Pour and serve depending on your taste buds! As you are drinking your cup, pay attention to the flavor so you can learn how to perfect the recipe, as described in step 7.

Step 7: Perfect the Recipe

You probably thought that enjoying your coffee was the last step in the recipe. When you’re first learning how to use eggshells in your coffee, the last step is perfecting the recipe to your exact taste buds.

Even if you don’t like completely strong coffee, you might like a little bit of bitterness. In contrast, you may love coffee so mellow that you need extra eggshells. Perfecting the recipe allows you to make the perfect coffee cup so that you enjoy it every time.

eggshells in a bowl
Image credit: Unsplash

After you make the first cup, note how you like or dislike the coffee. If it is too mellow, then add fewer eggshells. If you only used one, then simply up the ratio of eggshells to coffee. We recommend doing this one cup at a time. For example, make the ratio one eggshell per five cups of coffee if the 1:4 ratio was too mellow.

On the other hand, you could add more eggshells if the coffee still tasted too bitter. Once again, change the ratio one egg at a time. If the 1:4 ratio was too bitter, use one eggshell per three cups of coffee next.

Something else to keep in the back of your mind is that not all coffees have the same acidity levels. You may need to perfect the recipe with different types of coffee you drink. For example, one roast may need two eggshells, while the same amount of a different roast only needs one. Don’t be afraid to experiment.

Once you find the perfect recipe for you, stick with it, and enjoy the perfect cup of coffee every time.divider 2


Adding eggshells to coffee isn’t that difficult, but there are some tips to remember for creating the best tasting coffee with eggshells.

Credit: Bela Zamsha, Shutterstock

1. Only Use Fresh Eggs

Most importantly, only use fresh eggshells. They will produce the best flavor for your coffee. That is why we recommended cracking the eggs right before using the eggshells in the coffee. Though it may be tempting to save eggshells for later, they won’t produce as good of a neutralization effect.

2. Don’t Use Boiled Eggshells

Additionally, don’t use eggshells from boiled eggs. Even if the eggs were freshly boiled, eggs release sulfur compounds whenever they are cooked. This compound will affect the shell’s flavor permanently and permeate into the coffee. No one wants sulfur-tasting coffee.

3. Don’t Be Afraid to Experiment

Finally, don’t be afraid to experiment. As we mentioned above, everyone’s taste buds are different. Not to mention, every coffee type you get is different. Experiment with how many eggshells you like in each type of coffee. This ensures you find the best flavor, no matter the day or coffee type.

used coffee grounds and eggshells

Simple Eggshell Coffee

Putting eggshells in your coffee can seriously improve the flavor! Eggshells can make your coffee less bitter and less acidic. Here are the simple steps.
4.50 stars from 2 votes
Prep Time 6 minutes
Cook Time 4 minutes
Total Time 10 minutes
Course Drinks
Cuisine American
Servings 4 drink(s)
Calories 5 kcal


  • Coffee pot or maker
  • Coffee scoop
  • 2 small bowls


  • 1.8 ounces ground coffee
  • 32 ounces filtered water
  • 1 egg


  • Crack the eggs and save the yolk and egg white for another recipe.
  • Thoroughly wash the raw egg off of your shells.
  • Set up your drip coffee machine. Add water, a filter, and coffee grounds.
  • Lightly crush the shells with your hands, then add them to the ground coffee in your coffee machine.
  • Brew your coffee as usual.
  • Enjoy your flavorful, never-bitter coffee!


Calories: 5kcal
Keyword eggshell coffee

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Eggshells are the perfect way to make your coffee taste exactly how you imagine it should. The alkaline eggshells help neutralize the acidity of the coffee, mellowing out its flavor. The eggshells also helped to keep the coffee grounds down in campfire coffee. All around, eggshells help make your coffee taste perfect.

Use crushed, fresh eggshells by adding them to the coffee grounds, and brew as normal. It is as simple as that to get the perfect cup of morning Joe. Not to mention, you can even use the egg to create a delicious omelet too. What a great start to your day!


Featured image credit: Juver, Shutterstock


Kate MacDonnell

Kate is a lifelong coffee enthusiast and homebrewer who enjoys writing for coffee websites and sampling every kind of coffee known to man. She’s tried unusual coffees from all over the world and owns an unhealthy amount of coffee gear.

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