246 MODERN DAIRY PRACTICE. 



least when alone. The staff-bacteria have not disappeared 

 entirely, but are in a great minority. 



If, on the other hand, a sample of butter is soft and con- 

 tains large quantities of buttermilk, the bacilli will retain 

 their superiority all the time; the lactic-acid bacteria ap- 

 pearing first and later on others, giving rise to more or less 

 harmful fermentations. The importance of these condi- 

 tions for the keeping quality of the butter is evident without 

 any farther elucidation. 



If the butter be cooled, the increase of bacteria spoken 

 of will be found to cease very soon. The cooling of the 

 butter in tubs takes place very slowly, even if good refrig- 

 eration is used, and it seems especially to last long before 

 the cooling reaches the centre. My investigations show, 

 however, that it is not very important that the cooling act 

 on this part of the butter, as no significant bacterial growth 

 takes place in the same. Even a slight cooling of the 

 butter seems to be of benefit, if it is only sufficiently 

 prolonged. Professor Fjord,* who investigated this subject 

 found that a cooling to only about 43 F. proved sufficient to 

 check the spoiling of the butter; but, says Fjord, " it must be 

 remembered that this result could only be reached when 

 the butter was cooled from the time it was packed in the 

 creamery to within two or three days before the scoring 

 took place. If such cooling take's place in practice, both 

 creameries and the railroads and the steamers should have 

 cooling-rooms for the storage and shipment of the butter." 



It is not difficult to- arrange for the proper cooling of 

 the filled butter-tubs in our creameries. Ice-cellars are 

 also found on most farms in our country (butter should 



*See Eighth Report of the Copenhagen Experiment Station, 

 " On the Cooling of Butter," 1888. 



