METHODS OF COCOA ANALYSES. 949 
For the preparation of the sample for microscopical examination, a 
convenient portion is washed with ether by decantation in a small test 
tube; when the ether has evaporated from the residue, a portion is 
triturated in a small mortar with a small quantity of solution of chlori- 
nated soda until nearly or just decolorized; the mixture is then washed 
into a large test tube, or conical glass, diluted with much water, and 
set aside to settle. The sediment thus obtained is removed with a 
pipette for the microscopical examination. If both color and form are 
found necessary for the identification of any structures, the reserved 
portion of unbleached and fat-free material is used for this purpose. 
A knowledge of the structures of the spices used for flavoring cocoa 
preparations, sufficiently accurate to enable one to readily distinguish 
them from substances added as adulterants, is very important; to 
identify the individual spices when several have been used in the same 
preparation is a very difficult and generally a highly unimportant prob- 
lem. The ordinary flavoring materials are vanilla and cinnamon; cloves, 
nutmeg, mace, cardamom, Peruvian balsam, and artificial vanillin are 
also reported as flavoring materials. 
Starch, flour, and husks are the more ordinary adulterants to be 
detected with the microscope; Moeller! reports the materials most 
commonly used to be wheat and potato starches, next rice and arrow- 
root, and finally wheat, acorn, and rye flours, ground peanuts, and in 
malted: preparations raw malt as a substitute for malt extract; to these 
Macé? adds almond cake and sawdust. As the collecting of valueless 
waste products and the converting them into suitable materials for the 
adulteration of commodities of value has become a well-established 
industry, every investigator must be prepared to find many new sub- 
stances used for this purpose, and must not be disappointed if he finds 
none of those that have recently been reported. To know what to 
expect to find, he should consider the current prices, abundance, and 
suitability of available materials, as well as the results of previous 
investigations. 
METHODS OF ANALYSIS REPORTED BY VARIOUS CHEMISTS. 
A brief review of the methods that have been used or recommended 
for the analysis of cocoa and its preparation is here given. If any im- 
portant recently reported methods have been omitted, it is due to a 
greatly regretted and unintentional oversight. 
Preparation of the sample.—The method of analysis adopted by the Association of 
Swiss Analytical Chemists? directs that the substance should always be finely pow- 
dered or rasped, and kept in well-stoppered bottles. Bensemann‘ prepares the 
beans by grinding in a porcelain mortar, separates the husk by use of a knife, and 
1 Op. cit., note 3, p.940 of this work. 
?Macé, Les substances alimentaires étudiées au microscope. 
3 Vierteljahresschrift ii. d. Fortschritte auf d. Gebiete d. Chem. d, Nahr. u. Genuss- 
mittel, 1890, 2, 171. 
* Rep. f. anal. Chem., 1884, 4, 213. 
