CLARIFICATION OF MILK. 



203 



Table XXXI. — Presence of Fibrin in Commercial Milk before and after 

 Clarification. 



Micro-organisms in Milk. 



This particular aspect of the work seems~^to be the most popular for 

 testing the efficiency of the clarifier, and yet it has a faulty basis which is 

 not always considered in conclusions. Microbial counts may tell a verj^ 

 misleading falsehood unless the full story is told and the conditions are 

 fully understood. 



Several contributions have been made upon the removal or non-removal 

 of bacteria by the clarifier. Dr. J. Arthur McClintock' divided clarifiers 

 into three types, — A, B and C. 



Out of 26 tests made with type A, he obtained a reduction of 29.7 to 

 55.1 per cent. 



Out of 22 tests made with type B, he obtained a reduction of — 3.5 to 



29.8 per cent. Only two instances of increase occurred among the 22 

 tests. These account for the — 3.5 per cent. 



Out of 12 tests made with type C, he obtained a reduction of — 631 to 



35.9 per cent. Only in one instance among these 12 tests did he have an 

 increase, which alone accounts for the — 631 per cent. 



These results are so different from those which follow that the reviewer 

 hesitates to accept them without further data, and does not feel at liberty 

 to accord with the deductions from his study of the different types of 

 clarifiers. There must be influences at work which the writer failed to 

 record. 



There may be gleaned an astounding statement from A. J. Hinkelmann,- 

 in which he says: "I have found that the pathogenic bacteria commonly 

 met with are precipitated much more readily than are the non-pathogenic." 

 kSuch selective power on the part of the clarifier almost bespeaks super- 

 human capacity. It also indicates that if an organism is pathogenic 

 (which, of course, has only restricted application, depending upon species 

 of animal affected and other conditions) it possesses a distinctive specific 

 gravity. T)iis scarcely seems credible, although it can be understood 

 that some organisms are heavier than others. The division, however, 



» McClintock, J. Arthur: An Investigation of Clarification of Milk. The Milk Trade Journal, 

 1916, Vol. IV, No. 6. p. 10. 



■ Hinkelmann, A. J.: Micro-organic Weight. Reprint from the Illinois Medical Journal, 

 issue of March, 1916. 



