An anticaking agent is an additive placed in powdered or granulated materials, such as table salt, to prevent the formation of lumps (caking) and for easing packaging, transport, and consumption.
An anticaking agent in salt is denoted in the ingredients, for example, as "anti-caking agent (554)", which is sodium aluminosilicate, a man-made product. This product is present in many commercial table salts as well as dried milk, egg mixes, sugar products, and flours.
Natural anticaking agents used in more expensive table salt include calcium carbonate and magnesium carbonate.
Some anticaking agents are soluble in water; others are soluble in alcohols or other organic solvents. They function either by absorbing excess moisture, or by coating particles and making them water repellent. Calcium silicate (CaSiO3), a commonly used anti-caking agent, added to e.g. table salt, absorbs both water and oil.
Anticaking agents are also used in non-food items such as road salt, fertilisers, cosmetics, synthetic detergents, and in manufacturing applications.
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