Kala namak (, , ) is a kiln-fired rock salt with a sulphurous, pungent smell used mainly in the countries of South Asia. It is also known as "Himalayan black salt", bit noon, bire noon, bit loona, bit lobon, kala loon, sanchal, kala meeth, guma loon, or pada loon, and is manufactured from the salts mined in the regions surrounding the Himalayas.
The condiment is composed largely of crystalline sodium chloride heated with charcoal and several other herbal components lending the salt its color and smell. The smell is mainly due to its sulphur content; the salt is heated in presence of many herbal components and also contains greigite , Iron(II,III) sulphide). When whole, the salt is brown and black. When ground into a powder, its color may range from pink to black-brown to dark black.
Kala namak has been praised in herbal science and used for its perceived medical qualities.
Production
The raw material for producing kala namak was originally manufactured from natural halite from mines in Northern India in certain locations of the Himalayas, salt manufactured from the North Indian salt lakes of Sambhar or Didwana.
Traditionally, the salt was transformed from its relatively colorless raw natural forms into the dark-colored commercially sold kala namak through a reductive chemical process that transforms some of the naturally occurring sodium sulphate of the raw salt into pungent hydrogen sulphide and sodium sulphide. This involves firing the raw salts in a kiln or furnace for 24 hours while sealed in a ceramic jar with charcoal along with small quantities of harad seeds, amla, bahera, babul bark, or natron. sodium bisulphate, sodium bisulphite, sodium sulphide, iron sulphide, and hydrogen sulphide.
Sodium chloride provides kala namak with its salty taste, iron sulphide provides its dark violet hue, and all the sulphur compounds give kala namak its slight savory taste as well as a highly-distinctive smell, with hydrogen sulphide being the most prominent contributor to the smell. The acidic bisulphates/bisulphites contribute a mildly sour taste. Black salt is sometimes used sparingly as a topping for fruits or snacks in North India and Pakistan.
Kala namak is sometimes applied to tofu in vegan egg recipes.
Kala namak is considered a cooling spice in Ayurveda and is used as a laxative and digestive aid. It is used in Jammu to cure goiters. This salt is also used to treat hysteria and for making toothpastes by combining it with other mineral and plant ingredients.
See also
- Black lava salt
- Himalayan salt
- Jugyeom
- Thursday salt