Anticaking agents are used in such things as table salt to keep the product from forming lumps, making it better for packaging, transport and for the consumer.
http://en.wikipedia.org/wiki/Anticaking_agents

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Note added at 4 minutes (2007-04-24 09:54:05 GMT)
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Sarea care se obtine cu umiditate de max. 0,1% se trimite prin intermediul benzilor transportoare la faza de clasare pe site electromagnetice si apoi la tratarea cu antiaglomerant si iodat de potasiu, dupa caz.
http://www.krisar.ro/cacica.htm