PASTEURIZATION. 183 



is also essential that the pasteurizer should not leak. All the 

 steam turned into the pasteurizer should be condensed before it 

 is allowed to escape. 



The Cost of Pasteurization. — Dr. Storch in his 43rd report of 

 the Royal Agricultural Experiment Station, at Copenhagen, 

 Denmark, reports that it requires 80 pounds of steam to heat 

 1000 Danish pounds of milk from 40° C. to 85° C. This would 

 be equivalent under American conditions to about 90 pounds of 

 steam to pasteurize 1000 pounds of milk from 90° F. to 185° F. 



According to good authority it takes 1 pound of lump coal 

 to produce 6 pounds of steam. Calculating from this, it will 

 take 15 pounds of coal to produce 90 pounds of steam. If 

 coal costs $4.00 per ton, the cost of 15 pounds of coal would 

 be 3 cents. If the milk tests 3.6% fat, and calculated on 

 one-sixth overrun, the 1000 pounds of milk would produce 

 about 42 pounds of butter. The cost of pasteurizing the milk 

 producing 42 pounds of butter is then 3 cents, and the cost 

 of pasteurization per pound of butter would be .07 of a cent. 



Taking into consideration the cost of cooling, and counting 

 on about .03 of a cent for leaks invoh'cd during the process, 

 the cost of pasteurizing per pound of liutter would be about 

 .] of a cent. As a rule, the major portion of the cooling is done 

 with water, which at most creameries costs little or nothing. 

 For this reason the cost of coohng has been omitted. 



Advancement of Pasteurization. — During the last few years 

 pasteurization has gained favor with the American creamery 

 operators. It has been thoroughly demonstrated that if the best 

 product is to be manufactured it is absolutely essential that the 

 operator have complete control of the fermentations in the 

 cream or milk. This control of the fermentation can best be 

 accompHshed by the process of pasteurization. Pasteurization 

 has been gaining favor with the creamery operators owing to 

 its own merits. The Danish Government compelled the pas- 

 teurization of milk or cream as a safeguard against tuberculosis. 

 It was found not only that the system was efficient in this 

 respect, but also that it produced a more uniform product, with 



