STANDARDIZING MILK 



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Standardizing Milk 



It may be desirable to produce a milk standardized to contain a 

 fixed and constant percentage of fat. This is particularly important 

 for infant feeding. Or one may wish to supply a milk of unusual and 

 definite richness ; or again one may want to combine two lots of cream 

 of different fat percentages to obtain a cream of definite percentage. 



A very simple method of determining what amount of any given 

 two lots of milk or cream, varying in richness, is required for combina- 

 tion to obtain a milk or cream of definite fat percentage is given 

 below. This method of standardizing milk was devised by Prof. 

 R. A. Pearson, of Cornell University. 



One should construct a figure like the accompanying cut, and in the 



two left hand corners write the percentages of , fat in the two lots of 

 milk (or cream and milk, or two lots of cream, as the case may be). 



In the centre, place the percentage of fat required. At the right 

 hand corners write numbers which will be the differences between two 

 numbers with which they stand in line. 



Thus: If 4.7 and 3.4 are the percentages of fat in two lots of 

 milk— and it is desired to make a mixture containing four per cent, of 

 fat— subtract 4 from 4.7 and place the result (.7) at the lower right 

 hand corner. Subtract 3.4 from 4 and place the result (.6) at the 

 upper right hand corner. 



The result shows that it will take six parts of 4.7 per cent - milk > 

 and seven parts of 3.4 per cent, milk, to make a standard four per 

 cent. milk. 



