Isolation of B-carotenoids for yellow pigmentation

A pigment is a material that changes the colour of reflected or transmitted light as the result of wavelength-selective absorption. This physical process differs from fluorescence phosphorescence and other forms of luminescence in which a material emits light. Many materials selectively absorb certain wavelengths of light. Materials that humans have chosen and developed for use as pigments usually have special properties that make them ideal for colouring other materials. A pigment must have a high tinting strength relative to the materials it colours. It must be stable in solid form at ambient temperatures.