No. 6. 



DEPARTMENT OF AGRICULTURE. 



«33 



(1.) Clieese-Pi'oduciDg and Whey-Producing Solids in Milk. — Of 

 the milk constituents, most of the water, albumin and sugar goes 

 in to the whey, with more or less of the mineral constituecits, to- 

 gether with small amounts of fat and casein. We may, therefore, 

 call the albumin and sugar and water whey-producing constituents, 

 while the casein and fat are cheese-producing constituents. Of 

 course, some water and small amounts of albumin and sugar go ioto 

 the cheese. In the following table we illustrate how these different 

 constituents of milk are distributed in the whey and cheese: 



Table Showing Distribution of Milk-Constituents of 100 Pounds of 



Milk in Whey and Cheese. 



Milk, 



Whey. 



Cheese, 



c 



3 

 o 



c 



3 

 o 



c 



3 

 O 

 Ph 



c 



3 

 O 



c 



3 

 o 



B 



3 

 £1 



■3 



■a 

 c 

 3 

 o 



a 



3 



■a 

 c 

 3 

 o 



■o 



c 



3 



0.75 

 0.72 

 0.C3 



On an average, 49.5 per cent, of the milk solids goes into the whey, 

 and 50.5 per cent, into the cheese. In poor milks, a larger propor- 

 tion of the solids goes into whey; in ricih milks, a larger propor- 

 tion goes into chee&e; in other words, milk rich in fat contains a 

 larger proportion of cheese-producing solids than does milk poorer 

 in faj:. Put in another w^ay, of the solids contained in 100 poands 

 of average factory-milk, about G.25 pounds go into whey and 6.50 

 pounds into cheese. 



(2.) Loss of Milk-Fat in Cheese-Making. — For 100 pounds of milk, 

 there is lost in whey in cheese-factory work from 0.20 to 0.50 pound 

 of fat; the average is 0.33 pound. As we have stated previously, the 

 amount of fat lost in cheese-making is practically independent of 

 the amount of fat in the milk used. When a cheese-maker says that 

 he cannot make cheese from normal milk containing over 3.5 or 4 

 per cent, of fat without having extra large losses of fat in whey, 

 he classes himself as an incompetent workman. 



Why is it necessary to lose any milk-fat io cheese-making? We 

 have seen that fat is present in milk in the form of very small balls 

 or globules, distributed through the milk in enormous numbers. 

 Now, when rennet coagulates or solidifies the milk casein through- 

 out the mass of milk, the fat-globules are retained or imprisoned 

 38 



