244 MODERN DAIRY PRACTICE. 



so that no air-spaces will appear in it. The rancidity 

 seems to start from such interstices, the butter being also 

 often discolored in such places. The tub should always be 

 packed full of butter; rather than sending half -filled tubs 

 they should be left until next shipment. Neither should 

 tubs be sent containing soft butter that has not yet been 

 cooled for a sufficiently long time. Such butter cannot 

 stand transportation, turns easily off flavor, and suffers great 

 shrinkage. There is no harm done if these tubs are left 

 till next shipment, if the butter is well made and tubs 

 treated according to directions given. 



At most of our creameries ihe butter when once in the 

 tubs is not considered in need of any farther care on part 

 of the butter-maker, and it is largely left to its own fate. 

 The tubs are Itept in an out-of-the-way place, exposed to 

 all kinds of moisture and temperatures. But much is left 

 at stake in this way. As before, bacteria must be prevented 

 from injuring the butter, and this can most easily be done 

 by means of cooling. 



Bacteria in Butter. When packed a larger or smaller 

 number of bacteria is always found in the butter. The 

 number will differ according to the treatment which the 

 milk received and according to the kind of butter produced. 

 In a sample of sweet cream butter examined baeteriologi- 

 cally I. found a comparatively small number of bacteria an 

 hour after it was worked, and the different samples of 

 " Paris butter " (see p. 205) analyzed contained still fewer 

 such organisms viz., from 120 to 300 per c.c. As would 

 be expected, a far larger number have been found in fresh 

 sour-cream butter viz., not less than 2000-55000 per cc. 

 During the first days a perceptible increase in the number 

 of bacteria was noticed in all samples of butter, especially 



