770 OLEOMARGARINE. 



Bepresentative WILLIAMS. Will yon explain what is meant by the 

 figures opposite "oleic," nnder the head of "glycerides?" 



Dr. WILEY. When you combine glycerin with oleic acid, it forms 

 oleinj and that is the form in which it exists in butter. Palmitin, you 

 see, is the chief constituent of butter, making 40 per cent, altogether, 

 of the total. 



[At this point Dr. Wiley submitted the following:] 



Characteristics of certain fats. 



The composition of butter fats, as shown by the latest analyses, is exhibited in 

 the table. 



It should be mentioned in addition that butter fat has been found to contain 

 minute quantities of coloring matter lecithin, cholesterol (cholesterin) and phy- 

 tosterol (pliytosterin). 



Further, there is evidence to show that butter fat is not made up of the simple 

 triglycerides, but that it contains mixed glycerides of butyric, palmitic, and oleic 

 acids. Such compounds are represented by the formula 



C 3 H 6 (C4H 7 O 8 ).(Ci6H 31 8 ).(Ci8H 3 3O 9 ). 



The evidence of the presence of these compounds is obtained in the following 

 manner : 



" If a mixture of tributyrin, tripalmitin, and triolein be prepared and treated with 

 alcohol, it is possible to extract the tributyrin completely. With butter fat, on the 

 other hand, such an experiment can not be made a fact due, without doubt, to the 

 butyric acid being combined with certain higher fat acids, and the same glycerol 

 radicle." (C. A. Browne's recent article.) 



Beef fat and lard are composed of a mixture of the triglycerides of stearic, palmitic, 

 and oleic acids. 



Cotton seed oil differs from the two last-named by containing a large percentage 

 of the liquid glycerides, olein, and linolein. According to Hazura the ratio of oleic 

 to linoleic acids in cotton-seed oil is 3:4.5. 



Several investigators have found cotton-seed oil to contain from ' 1 to 2 per cent 

 of unsaponifiable matter. Blyth states that this nnsaponifiable matter is phytos- 

 terol (photosterin), which has the formula CseH^O and resembles in many ways a 

 similar product found in animal fats and known as cholesterol (cholesterin). 



Eepresentative WADSWORTH. What is palmitin! 



Dr. WILEY. It is a compound of palmitic acid with glycerin. These 

 acids, although they have different names, are very closely related. 

 This is simply a series of what is known as the fatty acids, of which 

 vinegar is the beginning. The substance we know as vinegar is the 

 lowest of this series ; and these fatty acids are formed by additions to 

 that substance. These are the fatty acids : 



[At this point Dr. Wiley exhibited two tables, of which the following 

 are copies:] 



Fatty acids. 

 Acetic aoid series: 



Acetic CsHiOs 



Butyric < C 4 H 8 O 3 



Caproic C Hi 3 O 3 



Caprylic C 8 Hi 6 O 3 



Capric 



Laurie 



Myristic 



Palmitic 



Stearic 



Arachidio 

 Oleic acid series : 



Oleic acid 

 Linoleic acid series : 



Linoleic acid 

 Glycerin C 3 H 6 (OH) 



(*188) 



