This method determines the vitamin C concentration
in a solution by a redox titration with potassium iodate
in the presence of potassium iodide. Vitamin C, more
properly called ascorbic acid, is an essential antioxidant
needed by the human bodyDue to this reaction the iodine formed is immediately
reduced to iodide as long as there is any ascorbic acid
present. Once all the ascorbic acid has been oxidised,
the excess iodine is free to react with the starch
indicator, forming the blue-black starch-iodine complex.
This is the endpoint of the titration.
The method is suitable for use with Vitamin C tablets,
fresh or packaged fruit juices and solid fruits and
vegetables.