266 DAIRYING. 



care in sterilizing the skim-milk and in handling the starter 

 is taken, the pure culture may be propagated in this manner 

 for months. With lack of cleanliness and care it must be 

 renewed every other week or oftener. 



While the use of pure cultures has not as yet become 

 general in American creameries, the agitation caused by 

 their introduction and the discussions in dairy papers and 

 dairy meetings which they have brought about have doubt- 

 less been of great benefit to our dairy industry in empha- 

 sizing in the minds of butter-makers the necessity of 

 thorough cleanliness in the creamery and the importance 

 of the proper conduct of the ripening process for the 

 manufacture of high-grade butter. They have enabled us 

 to make butter of uniform fine flavor and of greater keep- 

 ing quality than was previously possible. 



Where abnormal fermentations appear, and the butter 

 produced is diseased or "off flavor," the evil may be 

 remedied by the use of pure cultures. In case of the estab- 

 lishment of an export trade of American butter of high 

 quality, the pure cultures used in connection with previous 

 pasteurization of the milk or cream will prove of great 

 benefit, insuring uniform goods and perfect keeping quality 

 in the product. 



The use of pure culture-starters in the manufacture of 

 Cheddar cheese is of recent date, and but limited experience 

 has so far been gained in this line. According to the 

 testimony of some of our leading cheese-makers, and of 

 recent experiments conducted at Wisconsin experiment 

 station, their use for this purpose is very beneficial, cheese 

 of improved, clean flavor and high keeping qualities being 

 produced. Pure cultures may therefore be safely recom- 

 m.ended for this purpose. The general method of applica- 

 tion is similar to that followed in the manufacture of pure 

 culture butter. The starter is propagated in sterilized 

 milk and kept at 90° F. for one day, when it will be slightly 

 lobbered, having an acidity of about .8 per cent. Prof. 

 Decker, late of the Wisconsin Dairy School, gives the fol- 

 lowing hints on the use of the starter by the cheese-maker : 



"The starter is introduced into the milk by rubbing it 



