CONTROL OF WATER IN BUTTER 159 



use the following rule for calculating the per cent, of 

 water : 



Rule: Multiply the loss in weight during drying by 

 lOO and divide the result by the weight of butter used. 

 Example : weight of butter before drying is 10.45 grams ; 

 weight after drying is 8.90 grams. The difference 1.55, 

 multiplied by 100 and divided by 10.45 equals 14.83 equals 

 per cent, of water. 



MOISTURE TESTS. 



There are a number of methods in use for determining 

 the water content of butter, a few of which will be 

 described here. 



The Eclipse Method. This consists of a strong, 

 double-walled casting with a depression into which an 

 aluminum beaker fits. The casting is attached to a steam 

 pipe which allows steam under pressure to pass between 

 its walls. The greater the steam pressure the higher the 

 evaporating temperature and hence the shorter the time 

 required to evaporate. 



About ten grams of butter are placed in the aluminum 

 beaker and as soon as it begins to show a light brown 

 color the evaporation as a rule is complete. With the 

 steam pressure ordinarily carried in creameries (about 

 50 lbs.) the evaporation is complete in about fifteen 

 minutes. 



To make sure that all the moisture has been evaporated, 

 re-heat and re-weigh the sample. If the weight after 

 the first heating is the same as that after the second, 

 it is proof that the first heating was sufficient. 



The Eclipse method especially commends itself for its 

 simplicity. 



