Why Would You Put Eggshells in Coffee? Do They Make Coffee Taste Better?

Drinking coffee is always a matter of personal choice. It’s like your own private moment when you can drink whatever you want. No one will judge you. It’s just you and a cup of freshly brewed coffee just the way you like it.

I like my coffee black, most of the time. I enjoy light roast in the morning to accompany my breakfast meal. I take another cup just before lunch. In the late afternoon, when things usually get slow, I take another cup. I prefer a darker roast at this time of the day to give me a better boost for the remaining hours before I prepare dinner for the family.

Sometimes, my wife and I get another cup of coffee a couple of hours before bedtime. We enjoy having this quiet time when the little one is already asleep. We catch up and talk about how our day went, some plans for the week and just about any topic that comes our way. We often add some milk in our coffee for this late night coffee date.

How about you? How do you enjoy your coffee on a daily basis? Do you have a favorite add-on ingredient?

I know others like adding cinnamon, butter, cayenne or whiskey in their coffee. But, have you heard of putting eggshells in coffee?

Let’s find out why anyone would do this and what the perceived benefits of putting eggshells in coffee are. Who knows, you and I might end up trying it, too.

Why Put Eggshells In Coffee?

Why Put Eggshells In CoffeeEggshells can be added to coffee for their alkaline properties which can offset the acidity of certain types of coffees. Highly acidic coffee can be the result of brewing high altitude grown beans, brewing light roasted coffee beans, or by brewing your coffee too quickly. When alkaline eggshells are introduced the bitters in the coffee can be tasted more and the coffee takes on a more balanced flavor profile.

Now with that out of the way let’s learn more about why all this is the case.

What’s in an Eggshell?

When you crack open an egg, we often throw away the eggshells. But have you taken a closer look at the eggshell?

Imagine that the egg was fertilized, the eggshell would be the protective covering of a growing chick. It seems breakable, but, in reality, the eggshell is a tough cover that enables a chick to grow into its full-term.

Bumpy and grainy in texture, an eggshell is covered with as many as 17,000 tiny pores.

Eggshell is made up of calcium carbonate (CaCO3) crystals. It is a semipermeable membrane, which means that air and moisture can easily pass through its pores.

The shell also has a thin, outermost coating called the bloom, or cuticle, that helps keep out bacteria and dust. The composition of the eggshell is perfect enough to nurture and protect a living organism. With the right temperature from the mother hen, the eggshell serves as an incubator to support a growing life.

Basic nutritional value of an eggshell (1/2 teaspoon of eggshell)

Calcium – 900 mg

Magnesium – 24.0 mg

Phosphorus – 8.4 mg

Potassium – 8.0 mg

Sodium – 9.0 mg

That’s a ton of trace minerals in a ½ teaspoon of eggshell. However, if you are going to put eggshells in coffee, does it mean consuming the eggshells as well?

That will make coffee hard to drink, don’t you think?

How does one add eggshells in coffee and how does one drink it?

Why Put Eggshells in CoffeeAccording to the LIVESTRONG Foundation, eggshells are frequently used in making campfire coffee.

Campfire coffee is a method of boiling loose coffee grounds in a pot of water. Eggshells help keep the grounds in the bottom of the pot and also help to reduce the acidic profile of coffee brewed over high heat.

For those of us making coffee in more normal, every day drip coffee maker type of setting you can try using the following techniques to get eggshells working for you.

First start with the following:

  • Eggs
  • Drip Coffee Pot
  • Ground Coffee

A general guide to know the number of eggs you need is that one egg is good for four cups or less. If you are brewing more, adjust accordingly.

For eight cups, you will need two eggs. It will really depend on the coffee taste that you want to achieve. Even if you are brewing just four cups, you might want to add more eggshells if you want a smoother and lighter coffee taste.

Step 1: Crack the Eggs.
Get two bowls. Put the egg whites and yolks in one bowl and the eggshells in the other. You can use the whites and yolks for your omelet. As a guide, use one egg for a small pot and two or more for larger pots. You may want to do this step ahead of time, because after step 1 you’ll get to…

Step 2: Clean the Shells.
This may sound like a no-brainer, but do not forget to clean the eggshells. Use hot water to remove any egg whites on the shell. Make sure nothing is left. You just need the eggshells. Let it dry in the air or pat-dry using paper towels.

Step 3: Add Your Coffee.
Measure the right amount of coffee ground to every cup of water. Normally, a scoop of ground coffee is good for one cup. Do not add too much ground coffee because it will still taste strong and bitter, even if you add more eggshells.

Step 4: Add the Eggshells
Crush the eggshells in your hand and add them to your coffee grounds. When you crush them, be sure the pieces are small, but not so tiny they could accidentally mix with your coffee and end up in your cup. Aim for small flakes, not powder.

Step 5: Brew Your Coffee
Turn on your coffee pot and brew your coffee just like you normally do every day. The water will pass through both your coffee and the eggshells before they reach your pot.

Step 6:  Discard the Used Eggshells and Grounds
As soon as you are done and the freshly brewed coffee is transferred into individual cups, time to throw away everything. Never re-use these eggshells. They are good for one-time use only.

Step 7: Enjoy Your Coffee
You will instantly notice the difference in taste. When using brewed coffee with eggshells, the bitterness of the coffee is significantly reduced and you will taste the smoother and sweeter side of coffee.

If you have been used to bittersweet coffee and love it, you might be disappointed with the less bitter eggshell coffee. But come to think of it, if you love and prefer the bitterness of coffee, there’s really no point in adding the eggshells in the first place, right? For everyone else, if you want to drink coffee, but prefer a smoother blend, try adding eggshells to your brew.

Where did the idea of adding eggshells in coffee start?

There are several theories that explain the origin of this eggshell addition. The most common and popular belief is that the practice of adding eggshells in coffee started in Sweden, back in the 1900s and has been a common practice, since.

In one story from the past a grandmother was saving eggshells and putting those in their coffee pot. She used a double-boiler type steel pot with a glass plug between the upper and lower parts – grounds (and shell) on top, water in the bottom, and when it boiled the water rushed up into the upper pot, steeped, and then dripped back into the lower pot. The reason noted was that the coffee tasted better than the coffee that came from a normal coffee maker.

In a related story the practice of putting eggshells in coffee can often work for percolators because the eggshells keeps the ground coffee at the bottom. Also, the eggshells help remove the build up inside the percolator, which helps in cleaning the equipment. It’s also believed that using eggshells in coffee brewing reduces the bitterness and acidity of the coffee but I believe it simply neutralizes the acidity and enhances the other desirable flavors including the bitters which taste great when in balance.

Have you tried adding eggshells in your coffee?

I think I’ll give it a go one of these days. For the meantime, I’ll enjoy my coffee – black, bold and rich without egg shells brewed at just the right speed and temperature.

Brian Mounts

Head blogger, editor, and owner of "Top Off My Coffee", a website that has been educating readers about coffee brewing techniques and equipment since 2012.

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