
Part, 
ie 
ie 

470 Report oF THE CHEMIST OF THE = , 
cheese-making were complete enough to enable ohobseanattaee io x 
control every step of his operations, then the yield of cheese — ep 
‘would depend upon the composition of the milk. ie 
Now, it is well known that two and only two constituents of oe 
milk generally need to be considered in relation to cheese ; these 
two constituents are fat and casein. If the fat and casein are 
present in milk in uniform relative proportions, then the relation — 
of fat to yield will be a uniform one. If the relation of fat to 
casein varies, then the relation of fat to yield of cheese will vary 
similarly. In previous bulletins, we have tried to calculate the 
cor 
yield of cheese based on the composition of the milk and elimi- 
nate the other two factors mentioned above. Our method was to 
calculate the amount of water in the cheese so that it would be 
proportional to the solids. This method was fairly satisfactory, 
but was open to one objection, viz.: that the fat and casein of 
cheese do not retain moisture with equal power. It was suggested 
to the writer by Dr. 8S. M. Babcock, of the Wisconsin station, 
that fat should have credited to it the same producing power that 
it has when made into butter and that likewise casein should have 
credited to it the same producing power that it has when made 
into cheese without fat. It was further suggested by Dr. Babcock 
that some of his experiments indicated that the cheese yield 
- could be roughly calculated from the composition of the milk by — | 
multiplying the fat by 1.1 and the casein by 2.5 and adding the 
products, though he had no analytical data to show how nearly 
correct this might be. The writer adopted this suggestion as a 
basis for experiment. Preparing some pure casein, this wasdried __ 
and then allowed to soak up as much water as it would be likely  __ 
to hold in being made into green cheese. It was found that one 
pound of casein takes up water enough to increase its weight to 
2.25 pounds. If to this is added the amount of ash taken upin 
the same amount of cheese, the weight would be increased to _ 
just about 2.5 pounds. This process of calculating cheese yield 
has been applied to all our work and with most satisfactory 
results. We shall present yields of cheese calculated in the above __ 
manner alongside the actual yields found, for the sake of com- 
parison. The method has the additional advantage of being 
applicable to skim-milk or milk containing added cream with 
just as satisfactory results as when applied to normal milk, \) 




