190 SCIENCE AND PRACTICE OF CHEESE-MAKING 



being done by a cheese-maker when the percentage 

 of fat in whey exceeds 0.30, if the milk furnished 

 is in good condition in respect to cleanHness. An 

 average loss of 0.25 pound (4 oun ces) of fat for loci 

 pounds of milk indicates excellent work under factory 

 conditions ; this means that about 93 per cent of the 

 fat in milk is recovered in cheese and not over 7 per 

 cent lost in whey. 



The data embodied in the following table include 

 the results of several seasons' work in cheese-fac- 

 tories : 



AMOUNT OF FAT IN WHEY AT CHEESE-FACTORIES DUR- 

 ING SEASON 



Month 



Average 

 per cent of 

 fat in milk 



Pounds of fat lost in whey from 

 100 pounds of milk 



April 



May 



June 



July 



August . . . . 

 September 

 October. . . 



3.43 

 3.58 

 3.64 

 3.62 

 3.84 

 3.98 

 4.23 



Lowest 

 0.29 

 0.20 

 0.20 

 0.21 

 0.22 

 0.22 

 0.26 



Highest 

 0.42 

 0.50 

 0.36 

 0.45 

 0.40 

 0.46 

 0.44 



Average 

 0.36 

 0.35 

 0.28 

 0.32 

 0.34 

 0.37 

 0.33 



The tabulated results on the next page show the 

 relative amounts of fat lost in normal milks containing 

 different percentages of fat. These results are in 

 harmony with those of other investigators and the 

 facts all go to show that the loss of fat in cheese- 

 making is quite independent of the amount of fat in 

 milk. The variations that occur in loss of fat are 

 due either to the defective condition of the milk with 

 reference to bacterial content, or to some special fault 

 in the details of methods employed in cheese-making, 

 or to both causes. 



