78 MARKET DAIRYING 
Ee 
fat 
casein 
albumen 
sugar 
ash 
Az 
=09.%= solids not fat. 
A PRR. 
One NOS 
NOuo © 
Total 12.9%=total solids. 
Relationship of Fat and Solids not Fat. In normal 
milk a fairly definite relationship exists between the fat 
and the solids not fat. For example, milk rich in fat is 
likewise rich in solids not fat. On the other hand, milk 
poor in fat is also poor in solids not fat. As a general 
rule, an increase in the solids not fat always accompanies 
an increase in the percentage of fat. ‘The increase is, 
however, not quite proportionate, the fat increasing the 
more rapidly. 
Since the casein represents the most valuable constitu- 
ent of the solids not fat, the following ratio between this 
substance and the fat very well illustrates the relation- 
ship that exists between the fat and solids not fat in milk: 
According to Van Slyke. 
Per cent fat. Per cent casein. 
3.00 2.10 
3.25 2.20 
3.50 2.30 
3.75 2.40 
4.00 2.50 
4.25 2.60 
4.50 2.70 
Specific Gravity as Affected by Richness of Milk. 
The richness of milk seems to have but a very slight 
effect on its specific gravity. Usually a four per cent 
milk shows a slightly higher reading than a three per 
