Note 4 — Chapter I
Reading edition
The presence of aniline dyes may be detected by mixing a portion of the suspected sample with enough water to make a thin paste. Wet a piece of white wool cloth or yarn thoroughly with water and place it with the paste in an agate saucepan. Boil for ten minutes, stirring frequently. If a dye has been used the wool will be brightly colored; a brownish or pinkish color indicates the natural coloring matter of the fruit or vegetable.—Editor.