TREATMENT OF CREAM PREVIOUS TO THE CHURNING. 229 



are applicable in case of the shallow setting system of 

 creaming. In experiments in this line I prepared the acid 

 starter by means of pure cultures, in the manner given 

 before, added the same to the milk, and found that in this 

 way a much more rapid and more certain fermentation 

 was obtained than by the ordinary plan. The main condi- 

 tion of a successful outcome proved to lie in proper re- 

 striction of the fermentation, so that the casein of the 

 milk does not coagulate before the creaming was done. 

 The butter made kept very well, especially when the milk 

 was pasteurized and cooled previously to setting. 



Lactic-acid Bacteria. A large number of bacteria pos- 



process of butter-making to a certainty. By testing his cream in 

 the afternoon, the butter-maker will be able to set it to ripen at such 

 a temperature that it will show the proper acidity for churning the 

 next morning. 



In testing the milk for cheese-making the same directions are to 

 be followed, excepting that a much less acid condition is required ; 

 probably from 15-20 cc. will give the best results. The whole num- 

 bers are cubic centimeters ; the intermediate divisions are fractions 

 of a cubic centimeter. 



Precautions in Using the Test. The solution marked " Neutral - 

 izer" is prepared of a certain strength. It is essential that this 

 strength remain constant. Never let this solution stand without a 

 stopper. Keep in glass or stoneware." 



The necessary apparatus and chemicals may be obtained from 

 dealers in dairy supplies. Lately Prof. Farringtou has published a 

 method of testing the acidity of cream with alkaline tablets of a cer- 

 tain strength. For a description of the manner of procedure in ap- 

 plying the tablets, see Bull. No. 32, 111. Agr. Experiment Station. 



Concerning the relation of the acidity of the cream to the yield 

 of butter, see Sebelien, Landw. Versuc7is-Stationen, 34 (1887), p. 

 93 ; Manns, Bull. 9, 111. Agr. Experiment Station (1890) ; Wallace, 

 Bull. No. 22, Iowa Agr. Experiment Station (1894). 



