Bixa orillana is a small tree 20 to 30 feet high, leaves broad, heartshape,
pointed, flowers in bunches, rosecoloured fruit, heart-shaped, 1 1/4 inches
long, reddish brown, covered with stiff prickles. Annatto is obtained by
pulping the seeds, allowing the pulp to dry spontaneously and pressing it
into cakes, or the seeds are soaked in water, allowed to ferment, and when
the colouring matter subsides are collected and formed into cakes.
There are two forms of Annatto used in commerce, the Spanish made in Brazil,
which is hard, brittle, odourless, and is usually sent over in rolls; and
the French, or flag, Annatto which comes from Cayenne, and is bright yellow
in colour, firm, sort, and evil-smelling, owing to the fermentive process
used in which urine is utilized.
The French is superior as a dye. Annatto has a dull fracture, a sweetish
odour and a very disagreeable saline bitterish taste. It is inflammable,
but does not melt with heat; insoluble in water, though it colours it yellow.
The chief constituent is a red resinous substance named Bixin.
Medicinal Action and Uses
In the past it was used internally as medicine, but is now only employed
as a colouring agent for ointments and plasters, and sometimes as a substitute
for saffron. In South America it is largely used by the Caribs and other
Indian tribes to paint their bodies. South American Indians are said to
produce directly from the seeds, without fermentation, a brilliant carmine-like
In this country it is used for colouring cheese, inferior chocolate,
etc., and by the Dutch as a butter colouring. It is also used as a dye
for fabrics and in the manufacture of varnishes and lacquers.
Annatto is adulterated with ochre, sand gypsum, and a farinaceous matter.