154 



Testing Milk and Its Products. 



there is no need of using any preservatives for the milk 

 in this case. Fig. 54 shows a convenient rack for hold- 

 ing the test bottles used 

 in composite sampling 

 with a " one-third sample 

 pipette." 



Accurate results can be 

 obtained by this method 

 of sampling, if care is 

 taken in measuring out 

 the inilk, and if it is not 

 frozen or contains lumps 

 of cream. It is doubtful 

 if the method has any 

 advantage over the usual 



FIG. 54. Test-bottle rack for use in method of Composite Samp- 

 creameries and cheese factories. ling. If milk is delivered 



daily and each lot is sampled with the one-third pipette, 

 twice or three times the number of tests are required as 

 when composite samples are taken in jars and tested 

 once every week or ten days. This method furthermore 

 takes a little more time in the daily sampling than the 

 other, as the quantity of milk must be measured out 

 accurately each time. If the test bottle is accidentally 

 broken or some milk spilled, the opportunity of ascer- 

 taining the fat content of the milk delivered during the 

 three days is lost; if a similar accident should occur in 

 testing composite samples collected in jars, another test 

 can readily be made. 



186. Accuracy of the described methods of sampling. An 

 experiment made at the Wisconsin Dairy School may 

 here be cited, showing that concordant results will be 



