83 



MODERN METHODS OF TESTING MILK 



i" 



J \se 



6 



RAY'S APPARATUS 



r.HADY F03USE IN Sample. 



(6) Rubber stoppers. The rubber 

 stopper B is so acted upon in testing 

 by the heat and reagent, that a new 

 one is required after about 100 tests. 



Reagents. Reagents are required 

 as follows: 



(1) Amyl reagent. This consists of 

 a mixture of 5 parts of amyl acetate 

 and i part of amyl valerianate, and 

 these must be entirely free from water- 

 soluble impurities. 



(2) Alcohol. This is used for burn- 

 ing when gas is not available. 



Operation of the test. The details 

 of the method of determining water 

 in butter are performed as follows : 



(1) Preparation of sample See 

 p. 85. 



(2) Weighing sample. Place on 

 each pan one sheet of parchment paper 

 and balance accurately. Weigh ex- 

 actly 10 grams of sample (see p. 75), 

 plucing in center of paper. 



(3) Transferring sample to flask. 

 The paper, containing the lo-gram 

 sample, is folded in such a shape that 

 the paper and butter may be slipped 

 mto ^ as ^ ^ without losing any of the 



Addin S 



reagent. Fill the 



