18 



and soluble ash. This division is not strict , since a little fat and casein 

 go into whey and a little albumin and sugar go into cheese. Most of 

 the water of milk goes into whey (reference No. 3, p. 91). On an 

 average 49.5 per cent of the milk solids goes into whey and 50.5 per 

 cent into cheese. 



4. Amounts of milk fat and milJc casein in different milks. — Milk 

 casein varies in amount in different milks, but not as much as fat does. 

 The following table illustrates the relations of fat and milk casein in 

 factory milks: 



In general, when the fat in milk increases one-fourth of 1 per cent 

 the milk casein increases one-tenth of 1 percent (reference No. 3, p. 89). 

 Question : If a normal milk contains 3 per cent of casein, how much fat 

 should it contain? 



5. Increase of cheese yield with increase of fat in milk. — Fat and 

 casein of milk produce the solid portion of cheese. When fat increases 

 in milk, casein increases also. Hence milk richer in fat produces 

 larger yields of cheese (reference No. 3, p. 90). The yield of cheese 

 from milk varies as the amount of fat and casein in milk vary. 



Ratio of fat in milk to yidd of cheese. 



As the milk grows richer in fat the same amount of milk makes 

 more cheese. Question : How much cheese should be made from nor- 

 mal milk containing 5 per cent of fat? 5^? 6? 



6. Calculation of cheese yield from fat in milk. — In average factory 

 milk the approximate amount of green cheese from 100 pounds of milk 

 can be found by multiplying the per cent of fat in milk by 2.7 (refer- 

 ence No. 6, p. 433) ; the amount of ripened cheese is found by multi- 

 plying by 2.6. Examples (see p. 19). 



7. Calculation of cheese yield from fat and casein in milk. — A very 

 close approximation to cheese yield from any given milk can be found 

 when the amount of fat and of casein is known. Multiply the per 



