174 STATE BOARD OF AGRICULTURE. 



SO mucli water; but in spite of the water it ranks well with other foods in nu- 

 tritive value. A pound of milk is equal in food value to a pound of oatmeal or 

 rice, or whitefish ; while a pound of milk is worth four times as much as a 

 pound of potatoes or green vegetables, and a little more than bakers' bread. 

 One writer states as a result of his analysis of cows' milk, that when meat free 

 from bone is worth 25 cents per pound, fresh milk is worth 14 cents per pound. 



Milk is a white, sometimes a bluish or yellowish white liquid, a little heavier 

 than water. It may be defined as a solution of sugar and casein in water, in 

 which little globules of fat are floating. Milk also contains mineral matters, 

 such as a small amount of phosphate of lime, common salt and chloride of po- 

 tassium. These mineral matters are of some importance, as they go to make 

 up bone, the framework of the human body. But the most important sub- 

 stances in milk are casein and fat, the first forming the basis of cheese and the 

 second of butter. The greater the amount of these present the more valuable 

 will it be both for food and for dairy purposes. 



The following is the average composition of cows' milk : 



Sugar 4.54 per cent. 



Casein and albumen 4.37 " 



Fat - -. 3.80 '* 



Salts G4 " 



Water 86.65 " 



100.00 

 That is, in every hundred pounds of milk there are about S6f pounds of 

 water, 4| pounds of sugar, 4^ pounds of albumen and casein, 3 4-5 pounds of 

 fat, etc. Xow for the sake of comparison, let us see what milk from which the 

 cream has been removed, " skim milk," is made up of : 



Water 89.53 per cent. 



Butter (fat) 78 " 



Casein 2.95 '« 



Milk sugar 5.89 



Ash -. - 85 " 



100.00 



By comparing skim-milk with new milk it appears that most of the fat is re- 

 moved as cream, but not all. A little remains in the milk, and this, so far as 

 making butter is concerned, is an entire loss. 



It will be noticed that skim-milk contains a little less casein than new milk. 

 That is because some casein is removed with the fat. It is supposed that each 

 globule of fat is surrounded by a thin shell of casein. Cream varies a good deal 

 in composition, but it is generally made up of about two-tliirds water, one- 

 quarter fat, together witli some sugar, etc. The usual rule I believe is that a 

 quart of cream will make from 14 to 15 ounces of butter, but very rich cream 

 will make even more than this. 



Allow me to digress here to say, that in order to get the most cream from 

 milk, it is very important that it be kept at the right temperature. To test 

 tliis question, I took ubout twelve quarts of milk, and after saving out a little 

 for analysis, put the rest into three ordinary sized milk pans, filhng the pans 

 to exactly the same depth of two inches in each case. I then kept one pan 

 at the temperature of 32" F., another from 55° F. to 60° F., and the last from 

 75° F. to 80° F., allowed them to stand for exactly twenty-four hours, and 



