This salt used as a finishing salt both in North America and India, but in India is also important in recipes, particularly for Chaat Masala, a very important seasoning for street vendors. It is also included in some chutneys, sprinkled on fruit, and used to flavor lemonade and similar drinks. It is used by vegans to replace the sulfurous character of eggs.
Natural salts containing sulphates are mined in volcanic regions, and are then heated in a kiln for 24 hours, sealed in a ceramic jar with charcoal and possibly some other organic materials. This converts the almost colorless natural salts to Black Salt and develops the strong smell and taste of sulphur by converting the natural sulphates to sodium sulphide, iron sulphide, and hydrogen sulphide. Ground, Black Salt is usually a grayish pink color.
Today it is also manufactured from regular salt, combined with sodium sulfate, sodium bisulfate and ferric sulfate. This is heated in a kiln with charcoal the same as with the mined salts to convert those to sulfides.
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