42 QUESTIONS AND ANSWERS 



The dish is then half filled with boiling water and 

 the mixture of fat and water poured into a 500 c. c. 

 glass flask. The dish is rinsed several times with 

 boiling water and each time the rinsing is poured 

 into the flask. The flask is then filled to the 500 

 c. c. mark with boiling water and thoroughly 

 shaken. Then allow the contents of the flask to 

 cool, and after the fat has collected on top and 

 solidified, measure with a pipette 50 c. c. of the 

 clear solution beneath the fat and place it in a clean 

 glass dish. Fifty c. c. of a potassium chromate in- 

 dicator is then added and the solution titrated with 

 a standard silver nitrate solution. The strength of 

 this silver solution is such that I c. c. of it repre- 

 sents %oo of i per cent of salt. 



3. The Fitch salt test. A representative 3.5 

 gram sample of butter is placed in a 300 c. c. glass 

 flask and 180 c. c. boiling water added. The flask 

 is then corked and thoroughly shaken, care being 

 taken to remove the cork often to relieve pressure. 

 The mixture is then allowed to cool, and after the 

 fat has collected on top and solidified, 17.6 c. c. of 

 the clear solution beneath the fat is placed in a 

 white cup. Then 17.6 c. c. of potassium chromate 

 indicator is added, and the solution titrated with a 

 standard silver nitrate solution measured from a 

 graduated cylinder till the solution becomes a per- 

 manent reddish color. The number c. c. silver 

 nitrate used divided by 10 equals per cent salt. 



How should salt be added to butter? 



As soon as the butter has been properly washed 

 the salt should be applied by passing it through a 

 fine-meshed sifter in order to prevent lumps of salt 



