By JAMES HERVY HAGENIBUCH, PH. G.
Abstract from an Inaugural Essay.
There are several different ways of preparing chocolate. The best, and the one most generally used, is to take chocolate nibs (which are the seeds deprived of their outer covering) and grind them to a smooth paste in a mill with rollers, which are heated by passing steam into them by means of a pipe. To this paste the sugar and flavoring substances, principally vanilla or cinnamon, are added, and the whole reduced to a homogeneous mass, is moulded into cakes ready for the market. The heated rollers are used because they melt the fatty substance in the "nibs," and thus facilitate the making of the paste.
Unadulterated chocolate is compact, brittle, breaking with a smooth fracture, has a dark reddish brown color, and forms a perfectly homogeneous mass when worked into a paste. It should dissolve easily in the mouth, without leaving any gritty particles behind. The adulterations are very numerous, being composed principally of potato starch, flour, earthy matter, paraffin, tallow, lard, and other animal fats. Though nearly all the different kinds of chocolate contain starch it is nevertheless considered an adulterant. It makes a heavy and indigestible compound, because starch, unless boiled, is far from being digestible. Blythe says that it is considered an adulterant because it contains no nitrogenous principles, which are the main, and most valuable parts of the cacao, the principal ingredient of chocolate.
If this were the case, sugar also would be considered an adulterant, for it contains no nitrogen. There are certainly other reasons; one most likely is the solubility of sugar and insolubility of starch.
The chocolates are either sweet or bitter. The sweet chocolate is used mainly by the confectioners in making the different kinds of chocolate candies. When they use it for coating the chocolate drops it is sometimes adulterated with paraffin, which gives them their shiny appearance. The bitter chocolate is used principally as a nutritious drink; as a nutritive it stands much higher than either tea or coffee. Owing to the large quantity of fatty matter present in some brands, it is with all its nutritive powers apt to disagree with persons having very delicate stomachs; for this reason the English claim that the expression of the oleum theobromae from the seeds, makes them better for the manufacture of a chocolate, which is more easily digested, and though the oil is extracted still contains the active principles.
From several Philadelphia manufacturers of chocolate, specimens were obtained for examination. These were first exhausted with ether to remove all the fatty ingredients. The residue was next treated with twenty per cent. alcohol, and allowed to stand twenty-four hours to remove the sugar. The remaining residue was boiled in water, the liquid filtered through charcoal, and the starch precipitated with fifty per cent. alcohol.
From Baker's chocolate was obtained the greatest amount of fatty matter, it containing 45.8 per cent. which fused at 36° C. (96° F.), this being near the fusing point of pure cacao butter. It contains twenty-eight per cent. of sugar, some starch, and 3.1 per cent. of ash.
C. and A.'s contained 35 1/3 per cent. of fat, which fused at 38° C. (100°F), this being about 5°F. higher than the melting point of cacao butter; sugar, starch, a substance insoluble in cold or hot water, or hydrochloric acid, and 2.75 per cent. of ash were found.
E.'s cocoa contained thirty-eight per cent. of fat which fused at 37° C. (98° F.), sugar nearly forty per cent., starch eighteen per cent., and an insoluble substance. The ash was 2.3 per cent.
W.'s plain commercial chocolate, contained 26.5 per cent. of fat, which fused at 36° C. (96° F.), sugar forty-five per cent. starch, and 2.2 per cent. ash.
W's; sweet chocolate had but twelve per cent. of fat, and this fused at 38° C. (100° F.), nearly sixty per cent. of sugar, and 1.7 per cent. of ash.
A. & M.'s brand "A" contained twenty-six per cent. of fat, sugar, starch, and a quantity of coloring matter.
A. & M.'s powdered chocolate, contained fourteen per cent. of fatty matter, which fused at 39° C. (102° F.), sugar, and 4.4 per cent of ash.
The American Journal of Pharmacy, Vol. 57, 1885, was edited by John M. Maisch.