USE OF STARTERS. 1 95 



The plan suggested by Professor Storch was put into prac- 

 tical use in Denmark. In one sense this plan was not 

 new, having been in use for some time. For many years 

 butter-makers have known that, in winter weather, the 

 cream does not ripen very rapidly, and in order to pro- 

 duce satisfactory ripening in a convenient length of time 

 it has been necessary to hasten it with what was called a 

 " starter." A starter was simply a lot of already soured 

 milk or cream. The bacteria present in such cream are 

 already growing under favorable conditions, and, if added to 

 a new lot of cream, hasten the ripening process. The use of 

 such starters was adopted only in cold weather or in the 

 winter season, since cream ripened rapidly enough in 

 warm weather without them. The new feature of the 

 method suggested by Storch was the artificial preparation 

 of such a starter by the use of pure bacterial cultures ob- 

 tained by bacteriological methods. This method was soon 

 adopted by the Denmark butter-makers and extended 

 through the country. From Denmark the method was 

 adopted in North Germany and distributed itself more or 

 less in various other butter-making countries. Nowhere, 

 however, has this method been used to a very great extent 

 except in the countries of northern Europe. At the present 

 time the use of such cultures is practically universal in Den- 

 mark, common in North Germany and occasionally used in 

 other butter-making countries, especially at times when the 

 butter of a creamery shows some of the " faults " which are 

 the results of improper ripening of the cream. 



For using this method of controlling cream ripening, it is 

 necessary, first, to obtain a proper culture for the purpose. 

 This involves bacteriological work, and has proved to 

 be extremely difficult, and, at least for some places, quite 

 impossible. To obtain such a culture bacteriologists have 

 naturally had recourse to ripening cream and have selected 

 some type of bacteria that was found to be most common in 



