8 BULLETIN 904, U. S. DEPARTMENT OF AGRICULTURE. 
of vanes on the inside of the cylinder is carried partly up the side 
and then tumbled back among the pipes. These driers appear to 
be efficient and are generally used for this purpose. Improvements 
have been added from time to time, but the basis of operation is 
the same. After being dried, the germs are ready to go to the ex- 
pelling plant. 
EXPELLING THE OIL FROM CORN GERMS. 
While the method of handling and degerminating the corn is 
totally different in the dry and the wet processes, the operation 
involved in handling the germ material after it is dried and ready 
for the oil machinery is the same for both processes. At this point 
Fie. 7.—A type of moisture expeller used for wet corn germs and feed. 
it is logical to discuss the difference in the germ material as obtamed 
by the two processes. 
The germs separated by the dry process contain considerable 
portions from other parts of the corn, which on an average reduce 
the oil content to about 18 per cent. Approximately 6 per cent of 
oil remains in the cake. Dry-corn millers agree that half a pound 
of oilis an average yield from a bushel of corn, and if 12 per cent of 
oil from the germ is representative it follows that 4.17 pounds of 
germs are obtained from a bushel of corn. 
The germs separated by the wet process are much leaner eae 
is, they contain much less of the other parts of the corn, and there- - 
fore average a much higher percentage of oil, or about 45 per cent. 
lt is not usually possible, however, to obtain a cake with as low an 
oil content as that obtained by the dry process. The cake usually 
contains about 9 per cent of oil. Assuming that 14 pounds of oil 
represent the average yield from a bushel of corn, and that 36 per 
cent is obtained from the germ, the germ material obtained from a 
bushel of corn must be about 3.47 pounds. 
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