6 TESTING AND HANDLING OF MILK AND CREAM 
The milk is sucked into the pipette above the mark and the finger 
quickly placed on the upper end of the pipette and pressed firmly to 
keep the milk from running out of the pipette. The pipette is then held 
vertically, with the mark on a level with the eye, then by gently re¬ 
laxing the pressure of the finger on the end of the pipette, air is ad¬ 
mitted and the milk is allowed to flow slowly out until the top of the 
column of milk is level with the mark on the pipette. 
Running Milk into the Test Bottles .—The point of the pipette 
is placed in the mouth of the test bottle, holding the test bottle in 
an inclined position. Removing the finger 
from the end of the pipette, the milk will 
flow out of the pipette into the test bottle. 
The object of inclining the test bottle is to 
allow the milk to run down the side of the 
neck of the test bottle, thus allowing an 
exit for the air in the bottle. If this pre¬ 
caution is not observed, the air will bubble 
out and cause some of the milk to overflow. 
Blow the last drop of milk out of the pipette 
before removing it from the bottle. Each 
bottle should be numbered with a lead 
pencil, giving the same number to each bot¬ 
tle as that corresponding to the name on 
the milk sheet. 
Manner in which the tests should 
be transferred to the bottle. 
Adding the Acid .—The milk should be btetween 65 degrees and 
70 degrees F. when the acid is added. 17.5 c. c. of sulphuric acid of a 
temperature of 65 degrees to 70 degrees F. should then be added to 
the test bottle, its specific gravity being 1.82 to 1.83 at 60 degrees F. 
On pouring the acid into the test bottle, the latter should be held 
at an inclined position so that the acid will flow down the sides of the 
test bottle and not drop through the body of the milk in the bottle, the 
bottle being revolved so as to wash down all adhering particles of 
milk that may cling to the neck of the bottle. By observing this pre¬ 
caution, charring of the milk is avoided and also spilling of the acid. 
If the acid has been properly added there will be distinct layers of 
acid and milk in the test bottle without any black layer of partially 
mixed acid and milk between. 
Acid will eat holes in clothing wherever spilled on them. If any 
should be spilled on the skin or clothing, it should be quickly washed 
off with water. Color can be restored to clothing by treating the spots 
with ammonia water. 
Mixing the Milk and Acid .—Mixing the milk and acid is done by 
giving the test bottles a combined rotary and shaking motion, being 
careful not to allow any curd to get into the necks of the bottles 
Such mixing should be continued until all of the curd is dissolved and 
