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BUTTER-MAKING. 



are put up in powder form have the advantage that they can 

 be kept for a much longer time and still retain their vitality. 

 Both kinds as a rule are good while they are fresh. We give 

 below a list of the commercial cultures with which the authors 

 are familiar: 



Preparation of Commercial Starters. All of the starters 

 mentioned above have been tested and are known to produce 

 good results. The first step in the preparation of a mother- 

 starter (starterline) is to prepare preferably a glass jar or 

 bottle by thoroughly cleaning and sterilizing it. Glass jars are 

 used in preference to any other vessel, because if they are un- 

 clean in any way, it will show through the glass. Secondly, 

 there are no seams and no places on the inside which will cor- 



