COMPOSITION OF CORN MEAL. 7 



to the trade. So far there has not been opportunity to compare the 

 results obtained by this apparatus with those by the gravimetric 

 method employed in these investigations. 



FULL SET OF PRODUCTS OF TWO ROLLER MILLS. 



In Table 1 are given analyses of samples representing all the prod- 

 ucts and by-products obtained in two corn mills, one, grinding white 

 corn, located in the Middle West, the other, grinding yellow corn, 

 on the Pacific slope. 



PROCESS OF MANUFACTURE. 



A description of the process used in the white-corn mill, as furnished 

 by the chemist, follows: 



Number three * white corn is carried from the elevator or bin through a magnetic 

 separator to remove nails, etc., then through a screen to remove large pieces of cobs 

 or other foreign matter and over a fine screen to remove sand and grit. It is then 

 aspirated with a strong air current to remove impurities of a light, fluffy nature. 



The cleaned corn now goes through the tempering device and to the degerminator. 

 In the latter machine the kernels are broken open, the germs are partly broken loose 

 from the starchy portion of the grain, and the bran is partially removed. This broken 

 corn is dried and allowed to flow through the hominy separator. In this machine the 

 stock is led through a revolving sheet-iron cylinder, through the metal of which are 

 numerous narrow slots. Within this cylinder are beaters revolving in the opposite 

 direction from the cylinder. This removes some bran and most of the rotten grains, 

 which latter are shattered into very fine particles as they pass through the degermi- 

 nators. 



From this cylinder the stock passes through a sizing reel which removes all the 

 material fine enough to pass a number seven screen (seven meshes to the linear inch). 

 At the same time it is aspirated to remove dust and bran. The coarse portion from this 

 machine, which is now quite well cleaned, is passed through the first, second, and third 

 break rolls, being screened after each break, separating flour, meal, fine grits, coarse 

 grits, and hominy. 



As the products attain the desired degree of fineness they are aspirated thoroughly 

 before bagging. 



In the yellow-corn mill both dent and flint corn, either separately 

 or mixed, are milled, the process, as described by the head miller, 

 being as follows: 



The corn first passes through a degerminator which removes the bran and germ. 

 It is then thoroughly dried and allowed to remain in the bin long enough to cool to 

 about its normal temperature. From thence it passes through a series of rolls, being 

 gradually reduced to the proper fineness. The chaffy material is removed by suction, 

 after which the meal is sterilized at a temperature of 218° F., the process requiring a 

 little over three minutes. When the meal has cooled off slightly it is packed in sacks 

 or other suitable containers. 



ANALYSES OF THE PRODUCTS. 



A study of the analyses in Table 1 shows that the percentages of 

 fat and ash in the white corn grits and in the coarse yellow corn meal 

 correspond very closely to the percentages of these constituents 



1 This is the old No. 3 grade used by the trade prior to the adoption of the Government corn grades 

 in July, 1914. Corn graded No. 4 on account of moisture is often used. No. 2 corn is found compara- 

 tively rarely and then only in summer and early fall. 



