1 68 MILK AND DAIRY PRODUCTS PART 



Soltsien 1 should be used to test for the sesame oil. In this 

 method the fat is shaken with twice its volume of benzine and 

 half its volume of stannous chloride (SnCl 2 ) solution until the 

 liquids are thoroughly mixed, then placed in a water-bath at a 

 temperature of 40, which is raised to 80 C. when the sediment 

 has settled. During this time the level of the water-bath 

 must not be higher than the level of the benzine layer, and 

 every care taken to prevent the benzine from boiling. In the 

 presence of sesame oil the stannous chloride turns red. 



(b) Admixture with Cocoa-met Oil. 



A special fat, known as cocoa-nut oil or cocoa-nut butter, can 

 be extracted from the kernel of the fruit of the cocoa-nut palm 

 (Cocos nucifC'Ta). In the last few years the fat has come largely 

 into use as a food. When fresh, it is colourless and resembles 

 lard, but the taste and smell are peculiar and characteristic. By 

 means of a simple process, however, the taste and smell can be 

 completely removed, so that this cocoa-nut fat may be used instead 

 of butter in the preparation of food. Owing to its cheaper price, 

 cocoa-nut butter is now largely used in cooking, &c., in France, 

 England, and Germany. On account of the properties just 

 mentioned, cocoa-nut fat has been used more and more for the 

 adulteration of butter. Food analysts have, therefore, been 

 obliged to devise methods for the detection of this fat in butter. 

 These tests are based upon the characteristic composition and 

 peculiar properties of cocoa-nut butter. 



Two of the most commonly employed and most reliable tests 

 used in the analysis of butter the determination of the 

 refractive index and of the volatile water-soluble fatty acids 

 (the Reichert-Meissl number) cannot satisfactorily be employed 

 in this case. This is because the refractive index of cocoa- 

 nut oil, 33'5-35'5 divisions at 40, lies too near that of butter 

 itself to show any but a large adulteration. As regards the 

 Reichert-Meissl number, the cocoa-nut oil contains an unusually 

 high percentage of volatile acids 2 compared with other fats, 

 except butter. The Reichert-Meissl number of a cocoa-nut 

 oil lies between 6 and 8, and it is therefore clear that the 



1 Zeitschmft fur o/entliche Chemie, 1897, Vol. Ill, p. 495 ; also Pharm. Ze.it., 

 1901, Vol. XLVI, p. 850 



2 Between C and C 



