Konig and Wesener1 report a cocoa sweetened with saccharine, of which it contained 0.40 per cent. Another analysis is reported showing 0.76 per cent of saccharine (Chem. Ztg., 1888,106; also Konig).1

Stutzer2 has made a careful study of the effect of different processes of manufacture on the chemical constituents of cocoa, the quality of the product, etc. From the results of these investigations, which are given in the table on page 943, he draws the following conclusions:

(1) The roasting processes hitherto used are faulty. The duration of the roasting is too long. The temperature at which the process is carried on can not bo accurately regulated in most apparatus in use. Empyreumatic substances having unpleasant odors are imperfectly removed; hence it occurs that the aroma of the cocoa, in contrast with previous opinion, is only developed to be destroyed by the formation of empyreumatic substances.

(2) The faults mentioned disappear when the new, double, centrifugal roasting apparatus is used. This apparatus is much more suited to the purpose than apparatus now in use, and insures a marked economy of time and fuel. The duration of the roasting is short, the temperature of the inner part of the apparatus can be accurately regulated during the roasting and the empyreumatic gases are removed. The husks are more easily removed from the seed after the roasting and the losses of cocoa mass are smaller in consequence of this better separation. The natural aroma of the cocoa is better developed and, consequently, the poorer grades of cocoa can be more profitably marketed than was hitherto possible.

(3) The addition of potash, soda, or ammonia for the opening of cocoa is unnecessary, if the beans are roasted with the new apparatus. The additions at present in use (including ammonia) can be detected with certainty by the analysis of the cocoa powder.

(4) It is for the interest of the public and of the manufacturers that the artificial perfuming of cocoas be abandoned in future, and that only such preparations be brought into the market as contain the natural cocoa aroma in pure unadulterated condition. The technical arrangement of roasting apparatus and the methods of preparation heretofore in use seem to render this artificial perfuming necessary. This, as well as the addition of alkalis or ammonia, becomes unnecessary when Salomon's apparatus is used.

(5) The value of cocoa as a mere pleasant addition to the table depends entirely upon the content of the natural aroma. The finer it is the higher the price that will be paid for the product. The manner of preparation, especially the manner of roasting, in a marked degree influences the development and maintaining of the aroma.

The quantity of the physiologically important constituent appears to vary only slightly with the different kinds of cocoa and different methods of preparation.

(6) The value of cocoa as a nutritive material is essentially dependent on the content of the cocoa powder in digestible albumen. The amount of cocoa butter should not exceed.30 per cent as a rule. The digestible albumen can easily be rendered indigestible by too high a temperature in roasting. By examination of a well-prepared cocoa powder, we found the relation of the quantity of digestible albumen to the quantity of indigestible nitrogenous substances to bo nearly 4:3. If too high a temperature be used, this relation rises to 4: 4, or even to 4: 5. in the four samples investigated, No. 1, which was roasted in C. Salomon's apparatus, shows in this regard the most favorable and the Holland cocoa the most unfavorable relation.

1 Op. cit., note 8, p. 938 of this work. 2 Op. cit., note 3, p. 939 of this work.

In the same article he gives the following results to show the effect of roasting on the digestible albumen. The figures given are for the per cent of the total nitrogen existing in the form of indigestible nitrogenous substances:

A discussion of Stutzer's method for the detection of the use of fixed alkalis and ammonia will be found under the head of methods of analysis and under the head of judgment of samples.

Adulterations of cocoa preparations. - Perhaps no food material offers conditions so favorable for profitable adulteration and so well utilized by its manufacturers as do cocoa preparations. While a discussion of the adulteration of preparations sold in American markets is presented in the tabulated results of investigations given below and in the text accompanying them, a brief review of the favorite substances and methods for adulteration is not considered out of place here.

There is probably no more misleading or more abused term in the English language than the term "soluble cocoa." No cocoa in the market contains a very considerable percentage of matter soluble in water, unless the material so dissolved is foreign soluble material that has been added during the process of preparation. The term seems to be used to denote a preparation that allows none of the insoluble matter to deposit from the beverage prepared from it. This purpose may be accomplished in two ways, - the material may be so finely divided that a very long time will be required for its deposition, or foreign substances (as starch or sugar) may be added to render the liquid of so high a specific gravity, or so pasty, that the insoluble matter will not deposit. The first method is decidedly to be preferred; it accomplishes the object in view and puts the preparation in better condition for the action of the digestive juices - all this without the addition of a cheap diluent that is always at hand in every kitchen, should its use be desired. Any additions of this kind should be considered adulterations unless their nature and quantity are accurately stated.

Attempts at the preparation of easily digestible cocoas (preparations to which pepsin or other digestive ferments have been added do not come in question here, since the favorable condition of the preparation is not involved, but the supplying of a deficiency in the strength of the digestive juices) seem to fail in purpose and to be attended with the introduction of objectionable substances. The use of alkalis for this purpose is quite generally regarded as injurious, and the investigations of Stutzer1 show that the effect is opposite to that desired. He also states that these substances are used to aid the opening (aufschliessen) of the beans and not for the purpose of increasing the digestibility of the preparation.

1 Op. cit., note 3, p. 939 of this work.

The removal of the fat is not considered to be an adulteration when it is acknowledged. It seems important, however, that the public have a means of accurately knowing to what extent it has been removed. Concerning the removal of the fat Mace 1 writes:

The most frequent adulteration of cocoa powder consists in depriving it of a part of its fatty matter, cocoa butter. The best means of detecting this is to estimate the fat by means of ether. Cocoa thus adulterated has lost a great part of its nutritive power, and manufacturers often make great claims for their fraudulent practice, pretending to furnish a product which is more easily digested.

The adulterants added are reported to be, besides sugar and starches, other substances of organic and inorganic origin, to increase the weight and bulk; ferruginous and other pigments to restore the color of highly diluted preparations; and foreign fats to restore the normal percentage of fat or to give the preparation the plasticity required for molding.

As examples of the nature of adulterants reported, the following list of H. W. Warren2 may be cited: Sand, ferric oxide, clay, potassium chromate, copper sulphate, and nickel sulphate are used as coloring materials. Finely powdered tin is sometimes added to give the chocolate a metallic luster.

The husk, because of its coarse nature and consequent tendency to act as an irritating substance in the alimentary canal, and in consequence of its poverty in the constituents that render cocoa valuable, is regarded as an adulterant when not removed or when added to increase the weight or bulk of the preparation.