20 



BULLETIN 904, U. S. DEPARTMENT OF AGRICULTURE. 



are accomplished is a determining factor. A good grade of corn and 

 careful operation of the expellers are also necessary to obtain the 

 margin of profit indicated. The price of corn feeds is of course 

 dependent upon the cost of corn, and consequently the lower the 

 price of corn and feed the greater the balance in favor of oil expelling, 

 provided the price of the oil remains the same. 



Table IV gives data comparing the respective weights of oil left 

 in the oil cake obtained from a bushel of corn by the two types of 

 mills. 



Table IV. — Comparison of oil left in the oil cake obtained from a bushel of corn when 

 operating on dry-process and wet-jyrocess germs. a 



Items. 



Dry 



process 

 (hominy 

 mills). 



Wet 

 process 

 (starch 



and 

 glucose 

 plants). 



Germs obtained from 1 bushel of corn pounds . 



Oil in germs per cent. 



Oil left in cake do. . . 



Oil obtained from 1 bushel of corn pounds . 



Cake obtained do. . . 



Oil in the cake do. . . 



4.17 

 18 

 6 



.532 

 3.637 



.2182 



3.47 

 45 

 9 



1.372 

 2.097 

 .1887 



a The calculations in this table were made with the formula explained in footnote & of Table III. 



It is evident that in expelling dry-process germs a slightly greater 

 loss of oil results than when expelling wet-process germs, although 

 the percentage of oiTleft in the cake is considerably lower. 



PRODUCTION OF EDIBLE OIL. 1 



In 1919 there were 22 corn-oil producers in the United States, 

 but early in the year several of these had suspended operations on 

 account of adverse economic conditions. Of the 20 producers only 

 four, so far as is known, turned out refined or edible oil, one being a 

 hominy miller and the other three starch and glucose manufacturers. 

 This small number of refiners, however, is no indication of the rela- 

 tive quantity of oil which is refined for food purposes. According 

 to Bailey and Reuter, 2 111,000,000 pounds of corn oil were produced 

 in 1918, of which approximately 76,000,000 pounds, or about 70 per 

 cent, were refined for edible purposes. 



It is the practice of a few of the large operators to refine not only 

 the oil which is produced in their own plants, but also to buy large 

 quantities of crude oil from other producers for refining. Companies 



1 Since this paper deals mainly with the production of crude corn oil as a by-product in the corn-milling 

 industry, the refining of such an oil for edible purposes, which is an industry in itself is here discussed only 

 in a general way. A technical paper embodying the results of a detailed study of the preparation of edible 

 corn oil may be issued later. 



2 Bailey, Herbert S., and Reuter, B. E. The production and conservation of fats and oils in the United 

 States. U. S. Dept. of Agr. Bui. 769, sup., p. 4. 1919. 



