182 



go into solution. 1 Analyses of the portion soluble in alcohol show that 

 this is not the case. Tables I and II give the value of the constants as de- 

 termined for the portion soluble in cold alcohol, the portion not soluble 

 in cold alcohol, but soluble in hot alcohol, and the portion not soluble in 

 either hot or cold alcohol. 



Table I. 



Portion 



Soluble 



in Alcohol 



at 20 deg. C 



Portion Not 

 Soluble in 

 Cold Alcohol, 

 but Soluble 

 in Alcohol at 

 75 deg. C. 



Portion Not 



Soluble in 



Either Hot cr 



Cold Alcohol. 



Reichert-Meissl Xumber. . 



Melting point 



Soluble acids (as Butyric) 



48.1 

 16.9°C. 

 9.79% 



29.6 



31.5°C. 

 6.60% 



20.7 

 36.0°C. 



4.26% 



Table II. 



Solubility of butter fat in 95 % alcohol . 



At 20°C. 



1.1% 



At 75°C. 



3.3% 



The melting point of the portion soluble in alcohol at 20° C. is 16.9° C, 

 while that of the portion not soluble in either hot or cold alcohol is 36° C. 

 showing a difference of 19.1° C. The Reichert-Meissl No. in the portion 

 soluble in alcohol is 48.1, in the portion not soluble in alcohol it is 20.7, 

 showing a difference of 27.3. Since only 1.1 per cent of the fat is soluble 

 in cold alcohol, this would indicate that no tributyrin exists in butter fat. 

 This fact becomes still more evident by an examination of the molecular 

 weight of the glycerides soluble in alcohol and those not soluble in alcohol, 

 as calculated from the figures in Table VII. 



Cochran, "Action of Alcohol on Butter Fats," Analyst, Vol. 13, page 55. 

 Lewkowitsch, "Oils, Fats and Waxes," Vol. IT, page 675, 1000. 



