Composition of Annatto. 
551 
Prepared annatto cakes are generally stamped with the name 
of the maker, and sokl at v arious prices, according to quality. 
Besides the alkalies used for dissolving the pure colouring 
matter (bixin), chalk, lime, clay, fine brick-dust, and other 
bulky materials are generally employed by manufacturers of 
solid annatto. Soft-soap, train-oil, and other disagreeable 
smelling and tasting matters are also said to be largely used in 
the manufacture of inferior annatto cakes. Good annatto cake 
should readily dissolve in water with a bright orange-red colour, 
and deposit little sediment on standing. 
Inferior cakes dissolve with difficulty in water, forming a 
dark-brown muddy liquid, which on standing deposits a large 
amount of insoluble earthy matter. 
A sample of superior annatto cake analysed in my laboratory 
gave the following results : — 
Water lG-36 
Organic matters 27"68 
Oxides of iron and alumina 3'31 
Carbonate of lime (chalk) 31*9() 
Magnesia '11 
Sulphate of lime (gjqisum) "'SO 
Carbonate of jTOtash 9 03 
Carbonate of soda and a little chloride of sodium .. 0'77 
Insoluble siliceous matter 1"98 
100-00 
It will be seen that this cake contained a great deal of chalk, 
added for no other purpose than to increase its weight, and give 
it consistency. In inferior annatto the proportion of mineral 
matter is always large, and that of organic matters correspondingly 
small. 
A second and superior sample of annatto cake on analysis gave 
the following results : — 
Moisture lG-97 
Organic matters 38-00 
Carbonate of potash 'J3*25 
Chloride of sodium 1-58 
Magnesia -92 
Oxides of iron and alumina '37 
Phosphate of lime 
Sulphate of hme .. 3-79 
Carbonate of hmc 14-31 
Silica -aG 
100-00 
In this cake the proportion of organic matter, including pure 
colouring constituents, is much larger than in the preceding 
