THE CENTRIFUGE: KIND 325 



and one of acid. The graduated neck is also only about half as 

 long as in the case of whole milk. The fat test obtained is then 

 divided by two, since twice the 18 grams of sample had been 

 taken. Whey may be tested, however, in the ordinary whole 

 milk bottles with fair accuracy by using 17.6 c.c. of sample and 

 about one-half the usual charge of acid. 



Some fat is always lost in cheese making, that is, lost to the 

 cheese. At present this is frequently recovered by the separa- 

 tion of the whey by means of a cream separator, modified for 

 the purpose. The fat then is made tip into " whey butter." 

 Whey should not test more than one-fourth of one per cent (0.25 

 per cent), though 0.3 per cent is a rather more common loss. 



Testing Cheese — Ordinary cheese may be tested for fat by 

 means of the Babcock method. This is best accompli shed by secur- 

 ing a representative sample of the cheese in question by trim- 

 ming off the outside, dryer portion, using only the uniformly 

 moist center. This may then be cut into fine bits, on paper, and 

 nine grams weighed out as in cream testing. To the bottle con- 

 taining the crumbs of cheese about six c.c. of hot water should be 

 added. The whole mass is then stirred or shaken until warmed 

 throughout and softened. Ordinary testing acid is then added, 

 little by little, mixing and watching for color until the right 

 shade has been reached. A little more lukewarm water should 

 then be added to check further charring. The sample then is 

 run out the same as cream or milk. The amount of fat will be 

 found by doubling the reading obtained, since only nine, instead 

 of eighteen gi-ams of sample were used. 



The Centrifuge: Kind. — There are several milk-testing 

 machines on the market that have proven themselves thoroughly 

 serviceable. Aside from favoring the heavier aind enclosed 

 machine already indicated the writer has no particular choice, 

 provided the machine is to be used in a warm room. If, how- 

 ever, the testing outfit is to be placed in the ordinary milk room 

 where the air is often cold, a machine provided with an opening 

 below, through which or into which the chimney of a small kero- 

 sene lamp can be inserted is preferable to the machine tightly 

 closed below. It is essential that the samples be kept thoroughly 

 warm, even hot, not only at the time of reading the fat, but dur- 



