Calcium Disodium EDTA
What it does
Preserves colour/flavour by binding metals.
How it's made
Synthesised chelating agent.
Calcium disodium EDTA is a chelating (metal-binding) agent used to protect foods from the damage caused by trace metals: it locks up stray iron and copper ions that would otherwise speed up oxidation, so it preserves colour, flavour and vitamin content in products like canned vegetables, dressings and sauces.
Its core molecule, EDTA, is synthesised from ethylenediamine, formaldehyde and a cyanide source (or from related feedstocks), building the multi-armed structure that can grip a metal ion from several directions at once. This EDTA is then combined with calcium and sodium to make the specific calcium disodium salt used in food.
The salt is crystallised and purified to a white powder. The calcium disodium form is chosen deliberately because it already carries harmless calcium, so when it grabs onto unwanted metal ions in food it does not strip essential minerals from the body; it is used in small, regulated amounts precisely where metal-driven spoilage is a problem.
Possible reactions
Large amounts may bind essential minerals; generally safe at food levels.