How Iodised Salt Is Produced And What It Contains

Iodised salt is simply regular table salt (sodium chloride, NaCl) that has been fortified with a tiny, carefully controlled amount of an iodine-containing compound.

What Iodised Salt Contains

• Sodium Chloride (NaCl): This is the base ingredient, making up over 97-99% of the product. It is the chemical compound we know as "salt."
• Iodine Compound: A small amount of one of two main compounds is added:
  • Potassium Iodide (KI): A common fortificant, though it can be slightly less stable and may degrade in the presence of moisture.
  • Potassium Iodate (KIO₃): This compound is generally preferred in humid, tropical climates (like India) because it is much more stable and less prone to iodine loss from oxidation or moisture.
• Anti-caking Agents: Most table salts (iodised or not) contain agents like sodium aluminosilicate or magnesium carbonate to prevent the salt crystals from clumping together.
• Stabilizers (sometimes): If potassium iodide (KI) is used, a stabilizer like dextrose (a sugar) may be added to prevent the iodine from oxidizing and being lost.

How Iodised Salt Is Produced

The manufacturing process, known as fortification, is precise:

1. Salt Production: High-quality, food-grade salt is first harvested, either from underground mines (rock salt) or by evaporating seawater (sea salt).
2. Refining: The raw salt is washed, crushed, and purified to remove impurities.
3. Fortification: The chosen iodine compound (potassium iodate or iodide) is dissolved in water to create a solution. This solution is then sprayed evenly onto the salt as it moves along a conveyor belt or tumbles in a large mixer (like a pug mill). The amount is carefully calibrated to meet national health standards (e.g., a specific number of parts per million).
4. Drying: The now-fortified salt may be dried to ensure it is free-flowing.
5. Packaging: The iodised salt is immediately packed, often in opaque, airtight bags or containers. This packaging is crucial to protect the iodine from being degraded by air, humidity, and sunlight.