Semi-Centennial Volume. 



191 



endosperm often shows distinct parts, one of which is of a clear horny 

 texture, while the other is white and starchy in appearance. The physical 

 characteristics, and to a considerable extent the chemical characteris- 

 tics, of the corn kernel vary with differences in the relative amounts of 

 the horny and the starchy portions of the endosperm. Other parts of the 

 kernel which may be considered separately are the tip, by which it is 

 attached to the cob, and the starch which is associated with the tip. 

 Table III shows the percentage composition of corn and the distribution 

 of its constituents among the several parts. The figures are reduced to 

 a water-free basis and are given by Burtt-Davy,* who put them in this 

 form from the results published by Hopkins. t 



Table III. — Percentage Composition of Corn and Distribution of the Con- 

 stituents Among the Parts. Dry Basis. 



Com kernel . . 



Tip cap 



Hull 



Horny gluten 

 Horny starch . 

 Crown starch 

 Tip starch . . . 

 Embrvo 



Ash. 



1.52 

 .02 

 .05 

 .16 

 .09 

 .05 

 .04 



1.11 



Protein. 



11.28 



.10 



.24 



2 46 



4 25 



1.36 



.70 



2.17 



Carbo- 

 hydrates. 



82.49 

 1.28 

 5.48 

 7.96 

 38.61 

 15.92 

 9.36 

 3.88 



Fat. 



4.67 

 .02 

 .05 

 .55 

 .09 

 .05 

 .06 



3.85 



Table IV. — Percentage Composition of Feeds Obtained From Corn Grain. 



Com meal, feed. 



Corn germ 



Com germ meal . 



Corn bran 



Gluten feed 



Gluten meal.. 

 Hominy feed. . . . 



Fat. 



3.8 

 7.4 

 11.2 

 6.2 

 3.5 

 6.3 

 8.0 



Study of Table III gives one an excellent idea of the characteristics of 

 the different parts of the corn kernel and shows the basis for various 

 chemical food products. The richness of the embryo in ash and fat is 

 quite marked. In the manufacture of corn starch the embryo is sepa- 

 rated, and with it the ash and fat are carried to a large extent. The 

 embryo is also rich in protein. It may also be seen that the horny gluten 

 carries much less carbohydrates in proportion than does the horny starch, 

 while it is materially richer in ash. The figures are precentages based 

 on the whole grain. 



There are numerous food substances which consist of one or more 

 parts of the corn grain that have been separated by mechanical proc- 

 esses. Corn meal is made by removal of the hulls and most of the germs, 

 and finer grinding. Samp, hominy and grits are products in which the 

 body of the corn kernel is much coarser than is corn meal, but from which 



*Maize: Its History, Cultivation, Handling and Uses. 



t Bull. 5.^. III. .\e\. Kxpf. Stiilion. The Chemistry of the Corn Kernel. 



