Copper Complexes of Chlorophyll
What it does
Green colour.
How it's made
Chlorophyll treated with copper for stability.
Copper complexes of chlorophyll (and chlorophyllin) are more stable green colours made by modifying natural chlorophyll. They keep the plant-green shade but resist fading far better, which makes them more practical than plain chlorophyll for many foods, drinks and even toothpastes.
They are produced by first extracting chlorophyll from green plants such as grass, nettles or alfalfa with food-grade solvents. The natural magnesium atom at the centre of the chlorophyll molecule is then replaced with copper, which locks in a brighter, more stable green; a water-soluble version (copper chlorophyllin) is made by also treating it with alkali.
The copper-chlorophyll colour is purified and standardised for strength, and supplied in oil- or water-soluble forms. The small amount of bound copper is what gives the improved stability, and its use and copper content are controlled by food-colour regulations.
Possible reactions
Generally well tolerated.