676 



ANNUAL REf ORT OF TUB 



•f£. Dott. 



An iiis[)ection of Table No. 1 shows that the presence of either 

 cocoanut oil or pahnnut oil in cocoa fat would be indicated on 

 analysis by the following results: (1) A lowering of the index of re- 

 fraction and consequently a lower reading of the butyro-refracto- 

 meter both in case of the fat and of the mixed fatty acids. (2) A 

 lowering of the meltiiig point of the fat, and also of the mixed fatty 

 acids. (3) A marked diminution in the iodine number. 



The presence of any of the other vegetable oils or fats mentioned 

 in Table I would raise the index to refraction of the fat and of the 

 mixed fatty acids, lower the melting point of the fat aod of the 

 fat acids and increase the iodine number. 



The results of the analyses of oxaline, alberine, chocola and 

 caramel butter given in Table II indicate that these fats are of 

 animal origin and judging from the appearance of the crystals ob- 

 tained from solution in ether I am led to conclude that the most im- 

 portant constituent of each is beef fat. The lower index of refrac- 

 tion, the higher melting point, and lower iodine number of chocola 

 indicates that this fat contains a rather larger proportion of stearin 

 than is found in the other samples. The adulteration of chocolate 

 or cocoa butter with any one of these fats would be detected: 1st, 

 by the elevation of the melting point; 2d, by the high temperature 

 at which a deposit is obtained in Filsinger's test, and 3d, by the 

 microscopic appearance of the crystals obtained when the deposit 

 formed in Filsinger's test is allowed to crystallize from solution in 

 ether. 



The following table illustrates the effect of the addition of either 

 oxaline, alberiue, or chocola to cocoa butter so far as the above men- 

 tioned tests are concerned. 



TABLE III. 



Melting 

 Point. 



Filsinger's Test. 



Crystals Obtained from 

 Solution in Ether. 



C'Voua fat extracted in 

 laboratory. 



50 per cent, cocoa fat; 

 50 per cent, oxaline. 



50 per cent, cocoa fat; 

 50 per cent, alberine. 



50 per cent, cocoa fat; 

 50 per cent, chocola. 



33 Deg. C. 



42 Deg. C, 



44.5 Deg. C, 



45.5 Deg. C. 



No deposit at S Deg. C. 



Considerable deposit at 25 

 Deg. C, nearly filling 

 liquid at S Deg. C. 



Considerable deposit at 25 

 Deg. C. nearly filling 

 liquid at 8 Deg. C. 



Considerable deposit at 25 

 Deg. C, nearly filling 

 liquid at 8 Deg. C. 



Very difficult to obtain; 

 shows very little tend- 

 ency to crystallize at 

 ordinary temperature; 

 crystals very small. 



Crystals resembling those 

 obtained from beef fat. 



Crystals in large noE. 



Crystals resembling beef 

 fat. 



