APPLICATION OF REFKIGEEATION TO HANDLING OF MILK. 85 
The centralized, or main, creamery is usually located on a rail- 
road or, better still, at the intersection of two or more railroads. The 
cream-buying stations are distributed along the lines of the railroads 
in the most favorable locations for collecting cream. The collected 
cream is shipped to the centralized creamery, the time of arrival, of 
course, depending upon train schedules. In some instances cream 
arrives at practically all hours, both day and night. As soon as 
received at the creamery, the cream is sampled, weighed, and pas- 
teurized. After pasteurization the cream is cooled and run into 
vats where it is held until the following morning, when it is churned. 
Generally the churning and the working of the butter take place in 
the forenoon, although in some instances this work is done at any 
time that happens to be the most convenient. 
Usually the cream is ripe when received, and if churning is to be 
delayed the temperature of the cream is lowered to a point where 
the development of acid bacteria practically stops, at which tempera- 
ture it is held until ready to churn. 
In case a force is kept on duty continuously, the refrigerating plant 
may be operated 24 hours a day; hence, the size of the plant is ma- 
terially reduced from that required if the plant were operated only 
8 hours. Generally speaking the methods of operation employed 
in the centralized creameries are very similar to those of the local 
creamery, except they are on a more extensive scale and only cream 
is handled. 
CREAM-BUYING STATIONS. 
Cream-buying stations are established for the purpose of supplying 
the centralized creameries with cream by collecting the cream directly 
from the farmers and shipping to the main creamery. These stations 
are located at suitable points along the railroads in close proximity 
to a large number of farms. The cream is brought to the baying 
stations by the farmers, where it is received by the agent of the main 
creamery and held until a sufficient quantity is on hand to justify 
shipping. Generally no provision is made for cooling the cream at 
the buying stations. 
In figure 37 are given the weights of a gallon of cream containing 
varying percentages of fat. 
COOLING CREAM IN AUXILIARY CREAMERIES. 
The auxiliary creameries, commonly known as skimming stations, 
are erected for the purpose of furnishing cream to the main creamery 
without the inconvenience of having to haul the raw milk a long dis- 
tance. By separating the cream from the milk in the auxiliary cream- 
ery and hauling only the cream to the main creamery a great saving 
in time and labor is effected, as it is necessary to haul only about an 
average of 13 per cent of the total weight of the whole milk. 
