196 BUTTER 



CHAPTER XX 



Butter 



Butter consists of the fat globules of milk which have been 

 caused to coalesce and revert from their super-cooled and 

 emulsified condition to the solid form by the action of churning 

 or other mechanical treatment. As a result of churning, the butter 

 is obtained in the form of granules about the size of small shot, 

 but by subsequent processes of treatment it is worked up into a 

 homogeneous mass. 



In addition to the pure fat, butter usually contains a certain 

 percentage of water, and also a small quantity of other milk 

 constituents, such as protein and milk sugar. 



The relative proportions of the constituents vary slightly, and 

 depend upon whether the butter has been prepared from fresh or 

 ripened cream, while the percentage of ash depends largely upon 

 the amount of common salt added. 



Average Composition of Butter from Fresh Cream ( Unsalted). 



187. Determination of Water. 



From 15 to 20 grams of recently ignited pumice in 

 small pieces are placed in a porcelain dish, which is 

 then heated in the steam oven for an hour, and weighed 

 together with its contents after cooling in a desiccator. 



About 10 grams of butter are placed in a stoppered 

 bottle, and melted by immersing the latter in water at 

 about 40° C. The liquid is then shaken violently, while 

 allowed to cool until it solidifies, and about 5 grams 

 of the solid are then placed on the pumice, and the 



