72 MODERN METHODS OF TESTING MILK 



and i cc. of amyl alcohol. The operations are carried 

 out about the same as in the Babcock test. 



The "Sinacid" (no acid) Test. The distinctive fea- 

 ture of this test is that, in place of sulphuric acid, it 

 uses a patented mixture, consisting of sodium hydrox- 

 ide (caustic soda), sodium sulphate, and potassium 

 sodium tartrate (Rochelle salt) which, unlike sul- 

 phuric acid, is entirely free from any dangerous pro- 

 perties ; it uses also a colored alcoholic solution. After 

 mixing the "sinacid" liquid with the milk, the mixture 

 is heated to 200 F. for 5 minutes before being whirled 

 in the tester. The results do not always appear to 

 agree closely with those given by other tests, according 

 to the reports of some operators. There is, moreover, 

 some natural prejudice against using a process, any 

 part of which is patented. 



Gerber's "Sal" Test. Gerber has described a 

 method in which no acid is used, but a mixture con- 

 taining sodium hydroxide, common salt and Rochelle 

 salt ; in addition a small amount of isobutyl alcohol is 

 added. 



Wendler's "New Salt" Method. A mixture of 

 neutral salts is used consisting of citrate and salicylate 

 compounds. 



