Chlorophyll (E140) is the primary green pigment in all photosynthetic plants, extracted commercially from alfalfa, nettles, spinach or grass using organic solvents. Natural chlorophyll provides olive-green colour but is relatively unstable to heat, light and acid.
Available as chlorophyll a (blue-green) and chlorophyll b (yellow-green) mixtures. More stable derivatives (copper chlorophyll, chlorophyllin) are often preferred for food applications.