202 Milk and Its Products 



perhaps indefinitely, but such a starter will often 

 improve in flavor qualities, particularly if propagated 

 continuously in clean, sound, fresh, whole or skimmed 

 milk. Many butter makers employ to advantage the 

 practice of cultivating continuously in suitable small 

 glass vessels several "mother" starters, from which 

 they make selections from day to day of the best 

 flavored for use in ripening. 



The use of starters in ripening has another advan- 

 tage in that it makes it possible to first pasteurize the 

 cream before ripening and so get rid of or reduce the 

 effect of any undesirable fermentations that may be 

 already present. This is of particular advantage where 

 many lots of cream from many sources are brought to 

 a central factory for churning. Such creams vary 

 very much, even where, as is not often the case, none 

 are already actually contaminated with some actually 

 bad fermentation. By pasteurization and ripening with 

 a good, pure culture starter, such creams can be made 

 into butter of a good, uniform quality that would be 

 entirely impossible without pasteurization. 



The amount of starter used will vary from 2 to 50 

 per cent. Where a small amount is used, the purpose 

 is to start and encourage the development of lactic 

 acid through the whole mass of cream. Hence some 

 time must elapse before the full effect of the starter is 

 secured. Where a large amount is used, the purpose 

 is not so much to encourage the formation of the acid 

 as it is to impart directly the flavor already developed 

 in the acid of 'the starter itself. 



The purer, the fresher, and the better flavored the 



