Desi namak, also known as kala namak or black salt, is a type of volcanic rock salt with a distinctive sulfurous flavor, while iodized salt is table salt with added iodine. The key difference lies in their composition, taste, and processing methods.
Desi namak, or kala namak, is a unique type of salt primarily produced in the Himalayan regions. Its dark color comes from the presence of iron and other minerals. The manufacturing process often involves heating the salt with charcoal, herbs, and tree bark, which contributes to its distinctive sulfurous, pungent aroma and flavor, often described as similar to hard-boiled eggs. It contains sodium chloride, sodium sulfate, iron sulfide, and hydrogen sulfide, which contribute to its unique taste and smell.Iodized salt, on the other hand, is refined table salt to which a small amount of iodine has been added. This is done to prevent iodine deficiency, which can lead to health problems like goiter. Iodized salt has a clean, salty taste without the complex mineral notes of desi namak. The processing of iodized salt typically involves removing most of the trace minerals, leaving primarily sodium chloride.
When using desi namak, start with a small amount, as its strong flavor can easily overpower a dish. It's best used as a finishing salt or in dishes where its unique flavor profile is desired, such as chutneys, raitas, and chaats.