SAMPLING MILK AND CRSAM 



129 



at the end of the month and the patron is paid on the basis of 

 this average test. When this is done the time saved in sampling 

 permits the pipetting of the sample direct into the test bottle. 



At first glance and from the theoretical point of view this 

 method appears crude and lacking in accuracy. However, an 

 extensive series of comparative tests conducted by the writer 

 in co-operation with the Indiana Condensed Milk Company at 

 Sheridan, Indiana, in which over 5,000 samples were tested, 

 demonstrated very conclusively that the results of this inter- 

 mittent sampling approached the average of tests of daily 

 samples closer than did the results of composite samples, as 

 shown in the following table: 



Table 22. Comparative Accuracy of Different Methods of 

 Sampling Milk. 1 



1 Hunziker. Experiments conducted at factory of Indiana Condensed 

 Milk Co., Sheridan, Ind., November, 1913. Single samples, composite samples 

 (aliquot portions) and composite samples (equal portions) were taken from 

 each of 300 patrons daily for a period of 14 days. The single samples were 

 tested daily and the composite samples at the end of the 14 day period. 

 The figures in column "Average Test," first column, represent the average 

 of all tests of the samples of each patron for each method of sampling. 

 There were 4,800 (300x14) single sample tests, 300 composite sample (aliquot 

 portion) tests and 300 composite sample (equal portion) tests. The average 

 pounds of fat (second column) were determined by multiplying each single 

 and composite sample test by the respective pounds of milk these samples 

 represented, dividing the product by the number of samples tested. The 

 "Average Variation from Check Figures" (third column) was determined by 

 deducting the average pounds of fat of each method of sampling from the 

 average pounds of fat of all single samples, the average of the single daily 

 tests being accepted as standard and used as check figures. 



