Coffee lovers have strong opinions about their brew, and they also have some stellar hacks for getting the perfect cup. This includes mixing eggshells with the grounds.
Yes, you read that right, but don’t worry—you don’t drink shells. Instead, you add them to the coffee grounds when you’re brewing.
But why? Turns out, eggshells can make your coffee taste less bitter.
Naturally, coffee has a pH of about five, which places it on the acidic side of the pH scale. The calcium carbonate in eggshells has a pH above seven, making it alkaline and able to neutralize the acidity of coffee. When this happens, your brew becomes less bitter and more palatable.
But don’t just crack an egg and throw the shell into the filter. You should carefully wash them first (post cracking, obviously). Then, just toss the clean shells in with your ground coffee. A single shell per four cups of coffee is best.