280 REPORT OF THE CHEMIST OF THE 
It is a matter of practical interest and importance to know what 
the extent of such variations may be. 
Taking milk as it averages, we find the following variation of 
relation between fat and cheese yield in normal milks containing 
different amounts of fat. The cheese yield is based on a uniform 
percentage of water in the cheese, 37 per ct. 
TABLE I].— Ratio oF Fat to CHEESE YIELD IN NORMAL MILK. 
| Pace a RRP a AT I SE ENS SLE SY SE I FE ET Se OE DEEP RIESE ALAS 
Amount of cheese 
made for each 
pound of fat 
Amount of cheese 
Fat in milk. Caseinlin milk. made from 100 
pounds of milk. 
in milk. 
Per ct Per ct Lbs Lbs. 
3.00 Zou 8.30 PAST Gr 
3.20 220) 8.88 ye be 
3.50 2200 9.45 2.40 
Sao 2.40 TOZ03 PAO 
4.00 2.50 10.60 2.65 
4,25 2.60 Ui bya BY 2.63 
4.50 2.70 11.74 2.61 
4.75 2.80 12-31 2.59 
5.00 2.90 12.90 2.58 

Casein, as we have shown, does not increase as rapidly as fat 
does in milk, and, therefore, milk richer in fat usually contains 
less casein in proportion to fat than does milk less rich in fat. In 
harmony with this condition and as a result of it, the amount of 
cheese made for a pound of milk-fat decreases as the percentage 
of fat in milk increases. This is clearly shown in the preceding 
table. 
‘An interesting fact shown in this table is that the rate of de- 
crease of the ratio of fat to cheese yield is less rapid as the per- 
centage of fat in milk increases. Thus, in the case of milks con- 
taining 3 and 3.25 per ct. of fat, the decrease of cheese yield in rela- 
tion to fat is from 2.77 to 2.73, a difference of 0.04 pound; be- 
tween 3.25 and 3.50, and also between 3.50 and 3.75, the decrease 
is 0.03; for each 0.25 per ct. of increase of milk-fat; from 3.75 
to 4.75 per ct., the decrease in the ratio is only 0.02; and between 
4.75 and 5.00 per ct., the decrease is only o.o1. This is explained 
by the well-known fact that, in the case of milk rich in fat, a 
smaller proportion of the fat is lost in cheese-making than in the 
case of milk poorer in fat. 
THE RELATION OF MILK CONSTITUENTS TO COMPOSITION OF CHEESE, 
The composition of the solids of cheese (cheese minus water) 
depends practically upon the relation of fat and casein in milk. 
