Does Salt in Coffee Reduce Bitterness?

Why Adding Salt Makes Coffee Taste Less Bitter

Add a few grains of salt to make coffee taste less bitter.
Add a few grains of salt to make coffee taste less bitter. Toa Heftiba/Unsplash

You may have heard putting salt in coffee makes it taste better, potentially making bad coffee palatable. Is it true? From a biochemical perspective, adding a small amount of salt to coffee does make it less bitter.

In some countries, it's traditional to prepare coffee using brackish water or to add a small amount of salt to the water used to brew the coffee. The reason given is that adding the salt improves the flavor of the coffee.

As it turns out, there is a chemical basis for this practice. The Na+ ion diminishes bitterness by interfering with the transduction mechanism of that taste. The effect occurs below the level at which the salty taste would be registered.

How to Prepare Coffee Using Salt

You only need a trace amount of salt to counteract bitterness in coffee. You can add a pinch of coffee to grounds before brewing. If you're the type of person who wants measurements, start with 1/4 teaspoon of kosher salt per 6 tablespoons of ground coffee.

If you get a horrible-tasting cup of coffee, you can add a few grains of salt to it to try to fix it up.

Other Ways to Reduce Coffee Bitterness

  • You can cover some bitterness by adding sugar to coffee.
  • Another tip is to avoid overheating coffee. If coffee sits on a burner for a long time, heat breaks down some of the molecules, leading to a burnt and bitter flavor.

References

Breslin, P.

A. S; Beauchamp, G.K. “Suppression of Bitterness by Sodium: Variation Among Bitter Taste Stimuli” Chemical Senses 1995, 20, 609-623.

Breslin, P. A. S; Beauchamp, G.K. “Salt enhances flavour by suppressing bitterness” Nature 1997 (387), 563.

Breslin, P. A. S “Interactions among salty, sour and bitter compounds” Trends in Food Science & Technology 1996 (7), 390.