240 DOMESTIC ANIMALS, DAIRYING, ETC. 



The starter is at its best just as the curd becomes firm, and the 

 butter maker should plan to have this occur at the time he wants 

 it to put into the cream. A glass jar is the best vessel in which to 

 make a starter. The glass surface, being smooth, is easily cleaned, 

 and the butter maker can see what action is taking place while the 

 milk is souring. If there are gas-producing germs in the milk, little 

 bubbles of gas will form in the bottom and along the sides of the jar. 

 If these are formed the starter should not be used, as gas fermenta- 

 tions always indicate impurity, and the effects of the starter will not 

 be good. 



The amount of starter that should be used in the cream will 

 vary under different conditions. Ordinarily, if one is churning every 

 day, about 1 to 1% gallons of starter in 10 gallons of cream is the 

 right proportion. If it is necessary to hurry the process of souring, 

 more starter can be used, and vice versa. The temperature at which 

 the cream is set will influence the amount of starter to be used. If 

 the cream is cooled to about 60 F., it will require more starter than 

 if it is set at 70 F. Unless the butter maker has means of control- 

 ling the temperatures quickly, either by very cold water or by means 

 of ice, it is best to have the cream as cold as well water will make it 

 (which will usually be about 60 F.) when the starter is added. If 

 the cream is to be held for the next eighteen or twenty hours at this 

 temperature, the amount of starter to be added can be determined 

 by the butter maker after tw r o or three trials. Attempt should be 

 made to add just enough starter to have the cream soured properly 

 at churning time. No absolute rule can be given that can be de- 

 pended upon for this work. The butter maker must use his intelli- 

 gence and decrease or increase the amount of starter and raise or 

 lower the temperature of the cream in such a way that it will be 

 ripened and ready for churning at the right time. 



If the cream is not to be churned every day, but must be held 

 from two to four days before enough is secured for a churning, either 

 of two ways may be followed : A very small amount of starter may 

 be added to the first batch of cream, which will cause the gradual 

 development of the acidity, or the cream may be held sweet from 

 two to four milkings and then the starter added in a little larger 

 quantity, with a view to having the ripening completed about twelve 

 to eighteen hours after the last batch of cream is added. Here again 

 the butter maker must use his judgment and experiment until he 

 finds just the right quantities and the right time to add the starter. 



Whole milk can be used for making a starter, as well as skim 

 milk, but it is usually considered best to use the latter. The surface 

 of the starter should be skimmed off for a half -inch or so in depth 

 and thrown away. This is necessary because in opening the jar for 

 examination or for any purpose dust may have entered and formed 

 colonies of undesirable bacteria which will be growing on the sur- 

 face but have not reached any depth into the milk. When whole 

 milk is used this skimming is not desirable on account of the loss of 

 butter fat that would have risen to the surface. 



