Chlorophyll
Chlorophyll is the porphyrin most widely used as a natural colourant. Its widespread occurrence in photosynthetic tissue and its breakdown character have prompted many investigations concerning stabilization of the molecule. Loss of magnesium follows denaturation of the protecting protein in the chloroplast. Several processing techniques to minimize chlorophyll loss involve alkaline blanching and soaking media. Attempts to stabilize chlorophyll have centered on the substitution of the normal magnesium ion.