r6 DAIRYING 



gation. 



Second: The Artificial or Commercial Starters. 



544. These are of two kinds, the liquid, such as the O/ 

 Douglas Boston Butter Cultures, and S. C. Kieth, Jr., Baccillus 

 Lactis Acidi, which is shipped in four small glass vials in one 

 mailing case, and the solid cultures of Hansen, Ericsson and 

 Parke, Davis & Co. The commercial starter is designed to 

 supply a pure culture of bacteria, which may be transplanted 

 into skim milk and built up to a large starter. It was formerly 

 claimed that the buttermaker could be supplied with different 

 kinds of bacteria, and he could order the particular one wanted, 

 such as acid bacteria, neutral bacteria, and several other kinds. 

 At the present time it is very generally believed that some 

 variety of the lactic acid bacteria is more beneficial to both the 

 buttermaker and the cheese maker than any other kind, and the 

 manufacturers are dealing in this one only. 



545. The liquid cultures are short lived, but each package 

 is dated to show when the culture must be used. They also, 

 when fresh, begin to work quickly after being added to pas- 

 teurized skim milk. The solid cultures keep a year or more, but 

 are weakened by age and several generations must be propa- 

 gated* before they are used, as they improve with each transfer. 



546. The directions for using these cultures given by the 

 manufacturers are essentially the same in principle, but differ 

 somewhat in detail. A few of the more important instructions 

 regarding each culture are given in the following table. 



*The manufacturers of Hansen's lactic ferment recommend the propo 

 gation of three generations of the skim milk before using it as a starter in 

 cream. The dry powder is added to pasteurized skim milk which is allowed 

 to stand at 80 degrees F. until it begins to thicken. This is called startoline and 

 is added to a fresh lot of pasteurized milk to make a second startoline. This 

 second generation is propagated in a third lot of pasteurized skim milk; and 

 when this third generation has soured it is ready to be used in cream. A 

 small quantity of startoline is saved each day to make a new starter as it is 

 claimed that the germs in the dry powder are somewhat dormant and are 

 not aroused to their full activity until several transfers of them have been 

 made in skim milk. 



