Natural Colors Used In Foods
Natural colourants produced for use in an analogous way to the coal-tar dyes are crude extracts of pigments, which are basically unstable. The apparent stability of some food products owes more to the amount of pigment present than to the tinctorial power of the pigment itself.
For example, beetroot even after prolonged cooking retains an attractive deep red colour, but the extracted pigment is unstable. Anthocyanin preparations have found use in some products, but their colour variation with pH has restricted their use, mainly to acidic products. However, in nature, the flavonoids (Flavanoids are antioxidant molecules found in plant sources such as fruit, flowers, roots, stems, tea, wine, grains and vegetables. They are often responsible for the beautiful coloring of plant structures) produce colours from white through yellow, red and blue to black at the pH of cell sap. The potential colouring power of flavonoids is, therefore, great