How Eggshell Can Improve Your Coffee (A Quick Guide)

Last Updated on November 18, 2021 by John Moretti

Sugar, caramel syrup, creamer, and pumpkin spice all sound like an excellent addition to a cup of coffee, but the suggestion of eggshells to enhance your coffee experience? Now that just sounds outrageous – until you try it out for yourself!

Coffee was first brewed with eggshells in the early 1900s. The alkaline nature of eggshells helps balance the acidity of coffee, resulting in a smoother, less bitter cup of java. Eggshells are also used to settle the grounds when cooking coffee in a pot.

Coffee is all the rage, and everyone wants to create that ‘perfect cup’. You are probably feeling a little skeptical about throwing some seemingly useless and unsavory eggshells into your coffee, but keep reading to discover how and why this trick is totally worth it:

How Does Eggshell Improve Your Coffee?

how does eggshell improve your coffee

The History Of Adding Eggshells To Coffee

The idea of adding eggshells to ground coffee dates back to the early 1900s. This brewing technique is closely associated with the traditional ‘campfire’ or ‘cowboy’ coffee, which is made by boiling coarse grounds in water over a fire. 

The extreme heat from the direct flame and over-extraction resulted in bitter coffee, and it was difficult to avoid swallowing the coffee grounds that floated to the top. To solve both of these issues, crushed eggshell was added to the grounds during brewing.

What Does Eggshell Do To Coffee?

Coffee is naturally acidic, and this is what gives it a strong and bitter taste. Even though most people prefer a ‘strong’ cup of joe, the bitter aftertaste can be somewhat unpleasant. Highly acidic and bitter coffee can also be the result of:

  1. Excessive heat during the brewing process.
  2. Over-extraction of the coffee grounds.
  3. Extended contact between the coffee grounds and water.
  4. The use of poor-quality coffee.

Regardless of the cause, unpleasant, overly-bitter coffee can be avoided by adding eggshells to the grounds before brewing:

Eggshells are mostly made up of calcium carbonate, and this substance is highly alkaline. When eggshells come into contact with coffee during brewing, a chemical reaction occurs. The alkaline substance in the eggshells will neutralize, absorb, and reduce the coffee’s acidity. The result will be a beautifully balanced, mellow, and smoother cup of coffee.

Eggshells also come in handy when camping or hiking, when you cook coffee in a pot that does not separate the grounds. The eggshells help to settle and keep the loose grounds at the bottom of the pot so that you can avoid drinking a sandy cup of coffee!

5 Benefits Of Adding Eggshells To Your Coffee

Here’s why eggshells should become a part of your coffee-making ritual:

  1. Avoid the risk of drinking bitter coffee due to occasionally unavoidable factors such as poor-quality grounds, high heat, and over-extraction.
  2. Neutralize and reduce the acidity levels.
  3. An ideal method for people with sensitive stomachs who need to avoid highly acidic beverages.
  4. Settle and prevent the loose grounds from floating to the top when brewing coffee in a pot. This trick will make it easier to pour the coffee when it’s ready.
  5. A great way to reduce food wastage and make use of the entire egg!
  6. Enjoy a perfectly balanced, smooth, and aromatic cup of coffee!

How To Use Eggshells In Coffee

Are you ready to brew an eggceptional cup of joe?


  1. Coffee grounds
  2. Water
  3. Eggshell – Approximately one whole eggshell per four cups of coffee


  1. Coffee maker or pot
  2. Two small bowls
  3. Coffee scoop
  4. Coffee cups


  1. Crack open and pour the raw egg into one bowl and place the eggshell into the other. Why not prepare some delicious fried or scrambled eggs to go with your coffee!
  2. Thoroughly rinse the eggshell under hot running water, and make sure you have removed any leftover raw egg.
  3. Gently crush the eggshell to create slightly smaller pieces – this will enhance the chemical reaction. Ensure that the pieces are not too small, as they will filter through and land in your cup!
  4. Add the crushed eggshells to the coffee grounds and gently mix.
  5. Prepare your coffee machine, French press, or pot: Add water and the ground coffee with eggshells. Brew the coffee as you usually would.
  6. The brewed coffee will pass through the filter, grounds, and eggshells before it reaches your cup. If you are using a pot, the shells will help stop the grounds from rising to the surface, making it easier to pour your coffee.
  7. Discard the eggshells and used coffee grounds. Add them to your compost pile.
  8. Sit back, relax and enjoy every sip!

4 Handy Tips When Using Eggshells With Ground Coffee

  1. Try to use organic, farm-fresh eggs whenever possible.
  2. Avoid using shells from boiled eggs, as the cooking process causes the egg whites to release sulfur – and this won’t go so well with your coffee!
  3. Experiment and adjust the amount of coffee and eggshells used to suit your taste buds.
  4. It is not recommended to reuse the eggshells, as they will not be as effective.

Final Thoughts

Eggshells are a convenient, affordable, and effective way to reduce the acidity and temper the bitterness of your coffee – and a savvy way to settle loose grounds when you prepare coffee in a pot.  Who thought that some empty shells could create a perfectly smooth and balanced cup of deliciousness?