Yellow: Caramel or sugar color. A still more beautiful yellow is obtained by the use of an aqueous extract of saffron.
Red: Extract of cochineal.
Blue: Indigo-carmine solution.
Green: Mixture of indigo-carmine and caramel.
Violet: Mixture of extract of cochineal and indigo-carmine.
While gelatine colored with the above-mentioned coloring matter does not present such a beautiful appearance as the product colored with aniline colors, it is entirely harmless and suitable for culinary purposes.
Leaves of gelatine colored with aniline colors exhibit beautiful colors and are used for many technical purposes. The following colors may be employed:
Yellow: Picric acid soluble in hot water.
Red: Fuchsine or eosine.
Blue: Water-soluble blue.