PRODUCTION, COMPOSITION AND CHARACTERISTICS 33 



75°, somewhat higher for the first propagation with the 

 pure culture than for the subsequent transplantings 

 when the bacteria, more or less dormant in the dry 

 powder or tablets, have attained full vitality. Some 

 species of bacteria, as the Bacillus Bulgaricus, require 

 higher temperatures — 90° to 100° or even 110° — than 

 others ^ The culture having been thoroughly incor- 

 porated in the milk by vigorous and repeated stirring 

 or shaking, the milk is left at rest in an incubator or a 

 waterbath or WTapped in paper or cloth in a warm room 

 where an even temperature can be maintained, until 

 it is curdled, which may take 18 to 24 hours or even 

 longer for the first propagation. 



One part of this curdled milk is now added to 5 or 10 

 parts of fresh pasteurized milk and set to ripen in the 

 same way as described above, possibly at a little lower 

 temperature, and this is repeated every day, thus main- 

 taining the ''Mother Starter." After the second or 

 third propagation the bulk of each batch is used as a 

 starter in the larger lot of material to be ripened, be it 

 cream for butter or milk for cheese or for commercial 

 buttermilk, while a little is taken for maintenance of 

 the mother starter as described above. 



The avioujit of starter to prepare every day depends 

 upon the amount of milk or cream to be ripened and 

 the per cent of starter used in same. For instance, if 

 you have ten gallons of cream to ripen every day in 

 which you wish to use about 10% or 12% starter, or one 

 gallon, take a little less than one pint of the first or 

 second propagation for one gallon of milk; the next 

 day use one pint of this to add to a gallon of fresh 

 starter milk, and the remaining gallon to add to the 

 ten gallons of cream, and so on every day. 



