NATURAL STARTERS 339 



The kinds of bacteria which develop in the ripening 

 cream are of primary importance in the manufacture of 

 good butter, since the preponderance of a single prejudicial 

 species in it will often ruin the flavour and cause financial 

 loss. As already pointed out, in normal ripening there 

 is a succession of waves of growth of different kinds of 

 bacteria, and hitherto no complete solution has been 

 obtained of the problem of how to secure the presence 

 of the right kind of organism at the right moment in 

 adequate numbers. No single species isolated from 

 cream has been found to be productive of completely 

 satisfactory results when introduced and grown in sterile 

 cream. 



Tentative methods which go a long way towards 

 effective control of ripening are in use ; these consist in 

 the addition to the cream of what are known as " starters" 

 which are more or less pure cultures of one or two varieties 

 of bacteria. 



Two classes of starters may be recognized, namely : 

 (i) natural starters and (2) artificial or so-called "com- 

 mercial" starters. 



Natural Starters consist of milk or cream which has 

 been allowed to turn sour and ripen spontaneously ; 

 buttermilk from a dairy which is producing butter of 

 fine flavour and aroma may be included in this class. 



For the preparation of these home-made starters the 

 following procedure may be adopted. Select a healthy 

 cow in the herd, and after washing the udder and flanks 

 of the animal with soap and warm water, draw the milk, 

 rejecting the first few jets, into a clean pail which has 

 been sterilized by boiling water or steam. Cover up the 

 vessel to prevent the access of dust, and keep it in a 

 warm place, at a temperature of 65 to 70 F. in summer, 



