Adding a pinch of salt helps reduce the coffee’s bitter taste and enhances the other flavors of the drink. There are areas in the world, such as Vietnam, where it is common to drink coffee with salt.
A trick that has gone viral on social media suggests that adding a pinch of salt to a cup of coffee can help reduce bitterness and enhance other more subtle flavors of the drink.
Is there truth in this? According to science, yes. One study of 1995 published in Chemical Senses concluded that sodium chloride — table salt — manages to reduce the bitter taste and, consequently, enhances the other flavors of a food more.
This happens because we have different receptors on the tongue for every flavor. The salt receptor is known as the epithelial sodium channel, or ENaC. Bitter taste receptors belong to a family known as TAS2Rs.
When scientists mixed sweet and bitter components, they found that adding salt made the mixture get sweeter and less bitter. But this suppression does not apply both ways, as adding bitter components does not reduce the saltiness of a food.
How this suppression works is still unclear, but a study in mice in 2013 showed that while ENaC is sensitive to low levels of sodium chloride, at high concentrations salt also triggers sour taste receptors. and bitter, reports the Science Alert.
This technique is also used in agriculture. Salting the Brussels Sprouts, for example, it is a common practice to reduce its bitterness. There are still several regions in the world where drinking coffee with salt is common, such as Vietnam. In Sweden, there are also areas where it is tradition to add salted meat or cheese to coffee.
ZAP // 
