336 KiRKwooD AND GiES : Chemical Studies 



these variations by increasing or decreasing the proportion of fats 

 melting only at higher temperatures. These facts account for the 

 variations in the figures given for melting point. Its specific grav- 

 ity is 0.9 + . 



On heating to about 170° C, the oil gives off the odor of lactic 

 acid ; at a temperature of 300° C. acrolein may be detected. On 

 long-continued heating with nitric acid the following dibasic acids 

 are formed : succinic, adipic, pimelic, suberic and azelaic. Nitro- 

 caproic acid is also formed. * The oil is very soluble in all of the 

 well-known fat solvents. It contains some free fatty acid, but con- 

 sists chiefly of glycerides of caprylic, lauric, myristic and palmitic 

 acids, t Glycerides of caproic and capric acids are present in ap- 

 preciable quantity ; also a trace of stearin and some olein. | The 

 fat dissolves readily at a comparatively low temperature in an equal 

 quantity of glacial acetic acid. Such a solution becomes turbid at 

 40° C.§ By reason of its content of lower fatty acid radicles 

 cocoa-oil has a high saponification value. Cocoa-oil is particularly 

 resistent to the hydrating effect of superheated steam. || 



The following data were obtained for the percentage fat-content 

 in the fresh endosperm. The method of determination used was 

 Dormeyer's :^ 



Gen'l 

 123456 7 Average. 



Fresh endosperm, a. 38.27 40.01 36.71 35.10 34.60 38.90 38.60 

 /^. 36.14 40.54 35.02 34.90-34.10 40.70 38.40 

 Average, 37.20 40.28 35.87 35.00 34.35 39.80 38. 50 37.29 



The ether extracts containing the oil were free from lecithin 



*Schaedler: Technologic der Fette und Ode des Pflanzen- und Thierrichs, 843. 

 1892. 



f Ihe presence of palmitin (tri) is doubted by Ulzer : Chemisches Centralblatt, 

 II : II43. 1899. 



J The so-called " cocinic acid" or " cocostearic acid" derivable from " cocin " 

 or " cocinin " is, like the latter, a mixture. The former is a mixture of some of the 

 above fatty acids ; the latter of their glycerides. See Oudemans : Chemisches Central- 

 blatt, 192. 1861. 



^ Valenta. Quoted by Vaubel : Physikalischen und chemischen Methoden quan- 

 titativen Bestimmung organischer Verbindungen, i : 162. 1902. 



II Klimont : Journal of the Society of Chemical Industry, 21 : 126. 1902. 



^ Dormeyer: Jahresbericht iiber die Fortschritte der Thier-Chemie, 26 : 42. 1896. 

 The fresh tissue was finely divided and weighed, then dried to constant weight at 

 100-105° C. , and all of it extracted with anhydrous sulphuric ether. The usual amounts 

 of tissue were used. 



