38 



W. H. ELLIS ON ANALYSIS OF MILK. 



then extracting with a Soxhlet. This method gave lower total solids and higher fat than 

 Wanklyn's. 



While the committee was sitting, Mr. Adams laid before them his paper process. 

 Believing that the difficulty in the complete extraction of the fat could be best met by a 

 division of the milk solids as fine as possible, he conceived the idea of sucking the milk 

 up by a coil of blotting paper, drying, exhausting in a Soxhlet with ether, driving off the 

 ether, and weighing the fat and the residue, i.e., the solids not fat, asserting that thus 

 more constant results are obtained than by weighing the total solids directly. 



The committee adopted his process, but with certain modifications, viz., they recom- 

 mend to determine the total solids directly by drying five grams on the water bath to 

 constant weight, and to weigh the fat extracted from the coil, determining the solids not 

 fat by difference. 



The following are some results obtained in my laboratory by Mr. Adams's modified 

 process, compared with those obtained from the same milk by the granulation process 

 described above (A. ^ Adams's process. B. = Granulation process) : — 



It appears, from these results, that Mr. Adams's process gives rather lower solids not 

 fat and rather higher fat than are obtained by the process that I have described as the 

 one in use in my laboratory. The results are constant. I am satisfied that the higher 

 percentage of fat, obtained by the paper method, really represents more fat obtained, 

 that is, that the extraction is more perfect. I believe, indeed, that it is complete, and I 

 therefore agree with the Milk Committee in recommending the process for general 

 adoption. Should the process be adopted, it is clear that the old limit of 9 p. c. solids 

 not fat is too high, and must be at once abandoned. 



