Temperature of Ripening. 133 



On the other hand, a considerable number of fac- 

 tories in this country have secured an increased flavor 

 and quality in their product from ripening their 

 cream with the aid of either Hansen's ferment or B. 41. 



The present status of the whole matter seems 

 to be that the various commercial artificial ferments 

 are now prepared in such form that they are readily 

 transported, they retain their vitality for a consider- 

 able length of time, and are practically free from 

 any undesirable germs. Their use in careful hands 

 is likely to be followed with uniformly good results. 

 Still, where all of the surroundings are cleanly and 

 the atmosphere pure, the use of such artificial germs is 

 not necessary to produce butter of the highest quality. 



Temperature of ripening. — The various germs of 

 lactic fermentations find their optimum growth point 

 at from 80" to 90° F . , and milk or cream kept at those 

 temperatures will most rapidly become sour. The 

 effect of such high temperatures, while favorable to 

 the production of lactic acid, is less favorable to 

 the texture of the butter, and on this account it is 

 desirable to ripen the cream at as low a tempera- 

 ture as will insure a fairly rapid growth of the lactic 

 germs. A temperature of from 60° to 70° F. will 

 ordinarily bring this about. The amount of acid de- 

 veloped in any given length of time will depend not 

 only upon the temperature at which the cream has 

 been kept, but also upon the number and activity of 

 the germs originally present, so that if we have a 

 thorough inoculation to start with, a lower temper- 

 ature will be sufficient to cause the development of 



