£4 A Handbook for Dairymen 



working process according to the firmness of tlie 

 butter as determined by the chemical, physical and 

 mechanical properties of the butter fat, and in the 

 constant use of a reliable moisture test. This shows 

 the vital relation of temperature to ovei'-run. In 

 many plants the cost of manufacture, marketing and 

 profits must come from the over-run because the 

 fat is paid for at the same price per pound as the 

 butter. 



As a large percentage of butter is made during 

 the short season when there is a large production 

 of milk, it has to be held to supply the demand 

 during the rest of the year. Quality is maintained 

 by storing the butter in very cold refrigerators — 

 0° F. or below. If the quality of the butter is to 

 be maintained, the temperature of the refrigerator 

 must not fluctuate. The refrigerator should be 

 equipped with a recording thermometer with the re- 

 cording element located on the outside. This saves 

 opening the door to observe the temperature, and 

 also gives a record of the temperature. It is es- 

 pecially desirable if butter is stored for some one 

 else. Then, if it deteriorates in storage, the oper- 

 ator can produce his records of the temperature, 

 which at once show whether the deterioration is due 

 to temperature or to some other cause. The value 

 of such an installation was pointed out in Chapter I. 



Whey Butter. 



Whey, or the liquid portion of the milk left after 

 cheese making, contains a small amount of fat. The 

 amount Varies with the variety of cheese made, 

 usually from .8 to .3 per cent. Special separators 

 have been devised to separate this fat from the whey. 

 Cream rich in fat (60 to 75 per cent) is desirable. 



