Salt in Coffee?! A simple trick to save bad coffee


Hi everyone!

Right, so as the title says, I’m going to be throwing in some salt to coffee. Wait don’t leave, I haven’t gone mad!

This idea may alarm some people who heard of this for the first time. (I also was very skeptical) But it is actually a very classic way that some people enjoy coffee. It seems to have its roots in Ethiopia.

I don’t know the details about the science side of things, but apparently a tiny bit of salt acts to ease the bitterness and sourness of coffee.

So I did some experiments to see if it would work. Let me share my results


Let me stop you from sprinkling some salt directly into your cups. The amount of salt you need for this trick is very very little. It would be difficult to adjust the amount if you try to pinch some in. If you over do it, the results are quite disastrous.

The method I used is to first prepare some salt water of known concentration, and add this salt water to your coffee, while weighing of course.


I dissolved 1g of normal table salt in to 19g of water to get 20g of 5% salt water. The result is a pale white solution.

this is 1g of salt
dissolve it in 19g of water. it’s pretty strong

When you add 1g of this 5% salt water, that is equivalent to adding 0.05g of salt. I’m sure you can’t weight 0.05g accurately with your scale, right? This is why we need the salt water.

Trial 1: with Normal Good Coffee

Lets start with brewing some good tasty coffee. I used the HARIO Switch, please jump to this post for details.

I separated out 100g of this coffee to add salt water to. I kept the rest in a separate cup to the side as a comparison baseline.

Salt water 0.3g = Salt 0.015g

To start off lightly, I added 0.3g of salt water. I could not taste any saltiness in the coffee. But I also was not able to taste a significant difference in the coffee. When I compared it to the baseline, it maybe felt a tiny bit smoother, but I could have imagined this.

Salt water 0.6g = Salt 0.03g

Adding 0.3g more salt water, still did not result in any saltiness. The taste of the coffee did feel a bit softer, less punchy.

Salt water 0.9g = Salt 0.045g

By this point, I could taste the salt. But probably only if I knew there was some salt in it. If I wasn’t told, I would probably not be able to detect it. The coffee does taste smoother, softer with sort of the edginess from the bitterness / sourness reduced.

Salt water 1.2g = Salt 0.06g

With a total of 1.2g of salt water added, I could taste the salt. It’s not undrinkable, but I think this is already over doing it. But it was interesting that at this level, it kind of felt like the coffee had a bit more body, and texture.

Salt water 2g = Salt 0.1g

To see what would happen when if you added salt directly, I added 0.1g worth of salt. This would be the level that normal coffee scales will be able to measure.

It is clearly salty, and simply disgusting. Undrinkable… I did not think that salty coffee would be this bad.

So with this trial using good coffee, I was able to see the effect of salt to reduce the edginess coming from the bitterness and sourness.

But to be honest, this bitterness and acidity is a good part of the coffee. I personally thought that this was taking away from the potential of the coffee. So even though it was interesting, I would not try it again.

Trial 2: with Bad Coffee

So, is salt in coffee useless? Well, not so fast.

It seems that if you have some coffee that got too bitter or too sour for some reason, salt could help in making that better.

As the second part of this experiment, I intentionally brewed some bad coffee by grinding way finer than I should. The coffee tasted very sharp, overly bitter, but at the same time hollow. It probably was a result of uneven extraction.

Again, I separated out 100g of this coffee to add salt water, and the rest as a comparison.

grind was too fine

Salt water 0.6g = Salt 0.03g

As expected from trial 1, at this level the saltiness was undetectable. But there was also no noticeable change to the coffee.

Salt water 1.2g = Salt 0.06g

With this amount, the coffee did taste ever so slightly salty, but the undesirable sharpness was some what reduced making the coffee more drinkable. But it was not enough to make it into good coffee, just less bad.


To summarize my findings,

  • Salt does have an effect to reduce bitterness / sourness
  • For good coffee, the bitterness and the acidity is what makes the cup good. There is really no reason to reduce it with salt.
  • If you have some unsuccessfully extracted coffee from some mistake or old beans, salt could be useful to rescue the cup.
  • When you add salt, a good amount seems to be around 0.05g for 100g of coffee. A good way to add this minute amount of salt would be to make some salt water.

Let me know what you find if you give this trick a try.