UNITED STATES DEPARTMENT OF AGRICULTURE 
DEPARTMENT BULLETIN No. 973 
Washington, D. C. 
June 5, 1923 
MILK-PLANT OPERATION. 
By Clarence E. Clement, Market Milk Specialist, Dairy Division, 
Bureau of Animal Industry. 
CONTENTS. 
Page. 
The need for technical "knowledge 1 
Receiving milk at the plant 2 
Grading, sampling, and testing 3 
Pasteurizing and cooling 4 
Control of pasteurizing temperature 5 
Checking accuracy of holders 6 
Cooling 7 
Bottling and capping 7 
Man-hour requirements for bottling milk 7 
Comparison of labor costs in filling and cap- 
ping bv various methods 11 
Washing bottles 16 
Man-hour requirements for washing bottles . . 18 
Comparison of costs in washing bottles 20 
"Washing cans 25 
Sanitation in city milk plants 25 
Wastes incurred in handling milk 28 
Milk-bottle losses 29 
Goods returned from delivery routes 32 
Shrinkage in handling milk 33 
Checking milk through the plant 34 
Checidng goods handled at plant 34 
ChecKing the driver 36 
Checking the receiving and shipping clerks . . 36 
Number of men required to operate milk plants . 38 
Systems of buying milk 39 
Disposal of surplus milk 42 
Manufacture of by-products 44 
Weights of milk and cream 44 
THE NEED FOR TECHNICAL KNOWLEDGE. 
The successful operation of a milk plant requires, besides general 
ability, considerable technical knowledge and training. New milk 
plants are constantly being established, especially by organizations 
of producers or of producers and small dealers, and the question of 
management is of considerable importance. The success of new 
milk plants usually depends to a large degree on the manager; and 
capable managers are often difficult to find. Sometimes men can be 
obtained who have the proper personality and general business 
ability but lack the technical knowledge for successfully managing 
a milk plant. The purpose of this bulletin is to give such men, as 
well as men who are already in the business, information regarding 
methods used in operating milk plants successfully. 
The construction, arrangement, and equipment of milk plants 
have been considered in previous publications issued by the Depart- 
ment of Agriculture. 1 Certain information regarding operation was 
also included in these publications. This bulletin describes briefly 
the various operations in somewhat the same order as they occur in 
the ordinary city milk plant. 
1 TJ. S. Department of Agriculture Bulletin No. 849, ' 
and U. S. Department of Agriculture Bulletin No. 890, 
28554°— 23— Bull. 973 1 
City Milk Plants, Construction and Arrangement," 
"Milk-Plant Equipment." 
