508 EXPERIMENT STATION EECOED. 



the boiling point. The milk is then boiled 3 times. In the presence of woman's 

 milk the mixture becomes coffee brown or brownish violet, while cow's milk 

 takes on no coloration at all or only a very slight one. 



Application of miscibility curves to the analysis of butter, margarin, etc., 

 E. Louise (Arm. FaJsif., J, (IDJI), No. 32, pp. 302-305, pgs. 2; <ibs. in Jour. 8oc. 

 Chem. Indus., 30 (1911), No. 15, p. 965). — The author uses for the purpose a 

 cylindrical bath having concentric chambers, the outer one of which is closed 

 with the exception of 2 holes for the introduction of a thermometer and the 

 escape of the vapors formed. In the outer chamber some lubricating oil of 

 heavy specific gravity is placed, while the inner one is tilled with ordinary 

 petroleum oil. 



The procedure is then as follows: "Ten gm, of the melted and dried fat and 

 10 cc. of the ' typical ' petroleum oil are placed in a large test tube, which is 

 closed with a cork through which passes a thermometer, and is placed in the 

 inner chamber. The typical petroleum oil should be such that when 20 cc. 

 thereof are mixed with 10 cc. of absolute alcohol the turbidity temperature is 

 4.9*^ C, and with 5 cc. of alcohol, 4°. Increasing quantities of anilin are then 

 inti'oduced into the tube, the turbidity temperatures determined and the misci- 

 bility curves plotted. Five cc. of the anilin should give a reading of 69° when 

 mixed with 10 cc. of the typical peti'oleum oil, and 10 cc. a reading of 72°. 



"All the samples of butter fat thus examined gave curves of the same form, 

 approximating to each other and differing at the most divergent point by only 

 2°. Twelve samples of margarin gave curves considerably higher (about 8°), 

 while 'vegetaline' gave curves about 4° lower than those of butter. Samples 

 of different animal fats gave curves slightly higher than those of margarin." 



Butter adulterated with acetin, N. Takugl and D. Veknengo (Ghent. Zig., 

 35 (1911), No. 116, p. 1068) .—Butter was found adulterated with acetin. It 

 was also determined that mixtures could be easily prepared from margarin, 

 coconut oil and acetin which would give Reichert-Meissl-Wollny and acid figures 

 corresponding to those given by butter. 



For detecting such adulterations the method proposed is as follows: Ten gm. 

 of the butter and 50 cc. of water are brought into a flask, connected with a 

 reflux condenser, and heated on a water bath until the fat has become fluid. 

 During the heating process the mixture is repeatedly shaken. After cooling, 

 10 cc. of the aqueous solution is used for determining the Reichert-Meissl- 

 Wollny figure according to the usual method, and the result obtained multiplied 

 by 5. These figures are nil for margarin and coconut oil. If acetin is present 

 the Reichert-Meissl-Wollny figure reaches .30, while the acidity figure is 

 around 65. 



In regard to Halphen's reaction, E. Gastaldi (Abs. in Chem. Ztg., 85 

 (1911), No. 15, p. 688). — Despite the fact that numerous investigations have 

 been made with this reaction, the author points out that the function of the 

 amyl alcohol has never been discussed (E. S. R.. 25, p. 615). He finds that amyl 

 alcohol as such plays very little part in the reaction, as the pure neutral alcohol 

 practically free from pyridin bases gives a very faint coloration. When amyl 

 alcohol is left out, or the alcohol is replaced by another, only a red-orange 

 coloration is obtained and neA'er the wine-red color. Amyl alcohol can be re- 

 placed by a drop of pyridin, anilin, chinolin, from 2 to 3 drops of ammonia, or 

 by a concentrated solution of potassium or sodium hydrate. 



If in a test tube containing 5 cc. of the oil in question, 4 cc. of a 1 per 

 cent solution of sulphur and carbon bisulphid and 1 drop of pyridin are added 

 and placed in a boiling water bath for from 15 minutes to 1 hour, a red colora- 

 tion is obtained wheoi 0.25 per cent of cotton-seed oil is present. 



