CONDENSED MILK 7 1 



of the bottle by shaking. Raise the fat column 

 to the top of the scale by means of the acid and 

 water mixture, and whirl for five minutes. 

 Read promptly (see page 20) from the extreme 

 bottom of the fat column to the bottom of the 

 upper meniscus. Multiply the reading by 2, and 

 deduct 0.25; the remainder is the per cent, of 

 fat. 



If an electric centrifuge without heat has been 

 employed, the fat column will be somewhat cool 

 and should be heated, before reading, in a water- 

 bath about 60°. 



The same authors give the opinion that the 

 centrifugal methods are not sufficiently accurate 

 to be depended upon for determining if evapo- 

 rated milk is up to standard. The Rose-Gottlieb 

 method is best for this purpose. If the centrif- 

 ugal methods are employed, considerable allow- 

 ance must be made for inaccuracies. Results 

 obtained are inaccurate unless the fat column 

 is clear, with the meniscus at the bottom of the 

 column perfect and not distorted by either char 

 or milky appearance. 



The percentage of solids as calculated from 

 the sp. gr. is not sufficiently accurate to 

 determine whether the milk complies with the 

 standard unless the correction factor for the for- 

 mula of calculation is ascertained frequently by 

 the determination of solids by drying. 



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