114 



MANUAL OF MILK PRODUCTS 



has received the proper care, as directed on page 112, the gentle 

 shaking of the sample bottle and the pouring of the contents 

 from one bottle to another several times should be sufficient. 



Samples containing lumps of cream or granules of butter can- 

 not be tested properly without extra preparation. They should 

 be heated to at least 110 degrees F., or until all lumps of butter- 

 fat have melted and disappeared ; they should then be shaken 

 vigorously and pipetted into the test bottle at once. Even 

 with this precaution it is difficult to transfer to the test bottle a 

 representative portion from such a sample. 



Sour and curdy samples should be treated 

 as follows : add one-half teaspoonful of soda 

 lye or potash lye, shake, and let stand until 

 all lumps of curd have disappeared. The 

 sample is then ready for the test. When 

 testing samples to which soda lye or other 

 alkali has been added, the acid should be 

 added slowly and carefully to avoid accidents 

 and to prevent the loss of a portion of the 

 contents of the bottle by excessive efferves- 



cence. 



Milk test bottles (Fig. 11) 



Fig. 11. — The 

 standard milk test 

 bottle is graduated 

 to 8 per cent with 

 subdivisions of .1 

 per cent. 



The standard milk test bottle is the 8 per 

 cent bottle. This bottle is graduated to .1 per 

 cent. The main divisions represent 1 per cent. 

 The figures are located at the left of the 

 graduation. For detailed specifications for 

 "Standard Milk Test Bottles" see Agricul- 

 tural Experiment Station Circular No. 41. 



Measuring the milk into the test bottle (Figs. 12, 13) 



Use a standard 17.6 c.c. pipette and a standard 8 per cent 

 milk test bottle. Draw the milk from the properly prepared 



