ILLINOIS STATE DAIRYM'E'N''S ASiSOCIATION. 151 



tribute this dried cream with the sample so as to make it u 

 fair representative of the patron's milk. All this trouble can 

 be avoided if the persons taking the samples will use a little 

 care each day in handling the composite sample jars. Every 

 time a new portion of milk is added to it, the jar should be 

 given a horizontal, rotary motion. This will mix the milk 

 already therein and rinse off the cream that sticks to the 

 sides of the jar. It also prevents the surface of the milk from 

 becoming covered with a partially dried layer of leathery 

 cream. 



Composite samples having patches of dried cream on the 

 inside of the jar are the result of inexcusable carelessness or 

 ignorance on the part of the operator, who does not take ad- 

 vantage of this simple way of preventing it. The cream 

 which rises on composite samples each day can be evenly 

 mixed again with the milk, so that it will fairly represent the 

 different lots contributed to it for a week or more, if a little 

 careful attention is given to the daily handling of them. 



TESTING SOUR MILK. 



Sami^les of sour milk can often be satisfactorily tested 

 by adding to them a very small quantity of powdered alkali. 

 This will neutralize the acid of, the sour milk and dissolve the 

 coagulated curd so that the milk becomes thin again and can 

 be drawn into the milk measuring pipette. 



The complete action of the alkali ,on sour milk requires 

 a little time, and the operator should not try to hasten mat- 

 ters by adding too much alkali. An excess of alkali will 

 cause a violent action of the sulphuric acid on the milk to 

 which the acid is added that the mixture will often spurt out 

 of the neck of the test bottle when it is shaken for the pur- 

 pose of mixing the milk and acid in the test bottle. 



Satisfactory tests of sour, milk can only be made by using 

 a very small amount of the alkali and allowing the milk to 

 stand some time with frequent stirring until the curd is all 

 dissolved and the thick, sour, milk becomes thin. Such milk 

 may become dark colored by the action of the alkali, but this 

 color will not interfere with the accuracy of the test. 



The most important thing, to be remembered in sampling 

 milk is, the fact that the fat has a tendencv to rise to the 



