724 



Journal of Agricultural Research 



Vol. Xlf, No. II 



Attention has already been called to various methods of neutralizing, 

 purifying, and drying the esters, as described by other workers. Most 

 of these processes and innumerable modifications were given careful trial, 

 but the readiness with which at least a portion of the butter-fat esters 

 hydrolyzed precluded the use of water in their purification. This was an 

 extremely exacting condition and called for a salt soluble in alcohol, 

 neutral in reaction, and with dehydrating properties. Dry magnesium 



Fig. 3. — Apparatus employed in fractionation. 



chlorid satisfactorily met these requirements, and furthermore was cheap 

 and easily procured. On the addition of the dry salt in the presence of 

 ether, a rapid separation of esters was obtained. The underlying solu- 

 tion was drawn off by means of a separate ry funnel, and the esters were 

 purified by "shaking out" several times with ether and a saturated 

 alcoholic solution of magnesium chlorid. The ether facilitates the 

 separation and shouid always be added before the magnesium chlorid. 



