224 AGRICULTURAL BACTERIOLOGY. 



of cream is small, it is always necessary to allow it to accumu- 

 late for some days, till there is sufficient fora proper churning ; 

 during this period it is sure to undergo ripening without any 

 intention on the part of the farmer. This necessity started the 

 process of ripening. In ordinary farms the cream is left to 

 care for itself, and it is sure to be ripened by the time there 

 is enough to churn. But the centralization of butter-making 

 into creameries, where large quantities of cream are daily 

 handled, has put a new aspect upon the problem of cream- 

 ripening. The ripening will no longer care for itself, but 

 must be carefully attended to by the butter-maker, and, since 

 it is conducted on a large scale, it has demanded new ap- 

 paratus and new devices. The necessity for some accurate 

 means of controlling the ripening is becoming more and more 

 apparent with each step toward concentration of the butter- 

 making. The farmer may perhaps allow his cream to care 

 for itself since his product is so small. But such a plan would 

 ruin a creamery where there are thousands of pounds of butter 

 made each day. Only as the ripening can be controlled is 

 concentration of butter-making successful. 



There appear to be three chief purposes in cream-ripening. 



1. Ripening is believed to increase the yield of butter, for it 

 has been found by numerous experiments that the return in 

 the form of butter is larger from cream properly ripened than 

 from unripened or improperly ripened cream. This is true, at 

 all events, for gravity cream ; it is less significant, and perhaps 

 not true, for separator cream. In a large dairy business this 

 is, of course, highly important, for a saving of even a fraction 

 of a per cent, means much to a large creamery in the course 

 of a year. 



2. It is thought that butter made from properly ripened 

 cream has better keeping ijuaHtics than that made from cream 

 improperly ripened. This factor, however, is one of no very 

 great importance, and, moreover, is perhaps a little uncertain. 



