CHAPTER V. 



COMPOSITE SAMPLING. 



Where milk is bought on the fat basis, it is essential 

 that it be sampled daily as it arrives at the creamery. It 

 is not practicable, however, to make daily tests of the 

 samples because this would involve too much work. Each 

 patron is therefore provided with a pint jar to which 

 samples of his milk are added daily for one or two 

 weeks, the sample thus secured being called a composite 

 sample. A test of this composite sample represents the 

 average percentage of butter fat in the milk for the period 

 during which the sample was gathered. 



Careful experiments have shown that quite as accurate 

 results can be obtained with the composite method of 

 testing as is possible by daily tests, besides saving a great 

 deal of work. This has lead to its universal adoption 

 wherever milk is bought by the Babcock test. 



All composite jars should be carefully labeled by plac- 

 ing numbers upon them. These numbers should be writ- 

 ten in large indelible figures as exhibited by the composite 

 jar shown in Fig. 15. Shelves are provided in the intake 

 upon which the jars are arranged in regular consecutive 

 order. Numbers corresponding to those on the jars are 

 placed on the milk sheet opposite the names of the patrons 

 which should be arranged alphabetically. 



Taking the Samples. Whatever the method of sam- 

 pling, all milk should be sampled immediately after it 

 enters the weigh can, not, as is frequently the case, after 

 it is weighed. 



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