COMPOSITE SAMPLES 



103 



spill as little milk as possible around the neck, inside as well 

 as outside, of the bottle when the sample is put in. If the 

 milk is spilled there, it makes an unattractive appearance. 

 Very often it becomes moldy, and, as more milk is added and 

 the sample shaken every day, this mold gradually extends 

 down the sides of the bottle. This causes the composite sample 

 to be infested with undesirable growth, and to spoil sooner than 



FIG. 62. Testing-room in Model Dairy, St. Louis Exposition. 

 (Chicago Dairy Produce.) 



it would if greater care were taken in keeping the milk from 

 coming in contact with the sides of the bottle, before coming 

 in contact with the preservative. 



It is important also that the sample jars be well covered, 

 otherwise the moisture evaporates and causes the milk or cream 

 to dry up. It also makes the test unreliable by increasing the 

 per cent of butter-fat. A gentle rotary motion should be 

 given each jar when a sample is added to it to mix the cream, 

 which rises to some extent after the milk has stood a while. 



