Chelation describes a particular way that ions and molecules bind metal ions. Chelation is an equilibrium reaction between a chelating agent and a metal ion which forms a complex. Trace metal ions in foods can produce undesirable effects such as discoloration, turbidity,and oxidation.
According to the International Union of Pure and Applied Chemistry (IUPAC), chelation involves the formation or presence of two or more separate coordinate bonds between a polydentate (multiple bonded) ligand and a single central atom. Usually these ligands are organic compounds, and are called chelants, chelators, chelating agents, or sequestering agents.
Chelators are used in producing nutritional supplements, fertilizers, chemical analysis, as water softeners, commercial products such as shampoos and food preservatives, medicine, heavy metal detoxification, and industrial applications. chelating a metal ion prior to feeding the element to the animal.
Metal chelate compounds are common components of fertilizers to provide micronutrients. These micronutrients (manganese, iron, zinc, copper) are required for the overall health of the plants. Most fertilizers contain phosphate salts that, in the absence of chelating agents.
Chelation in the intestinal tract is a cause of numerous interactions between drugs and metal ions (also known as "minerals" in nutrition).
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