14 



CREAMERY BUTTER MAKING 



is one eight-thousandth of an inch, in the Holstein one 

 twelve-thousandth, while the average for all breeds is 

 about one ten-thousandth. 



Night's milk usually has smaller globules than morn- 

 ing's. The size of the globules also decreases with the 

 age of the cow. 



The density or specific gravity of butter fat at ioo° F. 

 is .91 and is quite constant. Its melting point varies 

 between wide limits, the average being 92° F. 



Composition of Butter Fat. According to Richmond, 

 butter fat has the following composition : 



Eutyrin 385 ) 



Caproin 3. 60 - Soluble or volatile. 



Caprylin 55 ^ 



Caprin i .90 



Laurin 7-40 



JMyristin 20.20 



Palmitin 25.70 



Stearin i .So 



Olein, etc 35-00 



Insoluble or 

 non-volatile. 



This shows butter fat to be composed of no less than 

 nine distinct fats, which are formed by the union of 

 glycerine with the corresponding fatty acids. Thus, buty- 

 rin is a compound of glycerine and butyric acid : palmitin, 

 a compound of glycerine and palmitic acid, etc. The 

 most important of these acids are palmitic, oleic, and 

 butyric. 



Palmitic acid is insoluble, melts at 144° F., and forms 

 (with stearic acid) the basis of hard fats. 



Oleic acid is insoluble, melts at 57° F., and forms the 

 basis of soft fats. 



