Kala Namak

Kala namak (“black salt” in Hindi), also known as Sulemani namak, isn’t actually black in color. If you look closely, you’ll notice it’s a very dark shade of red, and, when ground, the powder takes on a light pink appearance. This color arises due to the presence of iron and sulfur in the form of a substance called greigite, a mineral that is rich in a salt called iron sulfide. While the color is special, it’s the unique aroma that sets kala namak apart from other varieties and makes it invaluable in the kitchen. When dry, this salt has a mild eggy, sulfurous aroma. When added to water (say, in fruit chaat or in chana masala), that aroma becomes stronger. Why does kala namak have a distinct aroma when other salt varieties are odorless? It comes down to what is in it and how it’s produced. Kala namak is prepared by heating halite, a salt obtained from salt mines in parts of northern India and Pakistan. The salt is heated for several hours, which helps develop its characteristic smell, along with amla (Indian gooseberry) and haritaki: two types of fruit-bearing trees called myrobalans. Both the iron salt and the combustion of the plant material help develop the flavor of this salt. In contrast, when salt water is evaporated using heat from the sun or a fire, the result is a flaky salt such as Maldon (pyramidal crystals). Like kala namak, kosher salt is also obtained from salt mines, but is extremely pure and contains only sodium chloride and nothing else.