AGRICULTURAL CHEMISTRY 



composition. As the result of a large number of analyses 

 made by the Department of Agriculture, the following 

 conclusion is drawn : "A study of all the analyses which 

 have been made reveals the fact that maize is one of the 

 most un variable of the cereals, maintaining under the 

 most different climatic conditions, a most remarkable uni- 

 formity of composition, varying chiefly in the size, color, 

 and general physical characteristics of its kernels rather 

 than in their composition." 



From the figures given at the close of the next chapter 

 it will be observed that corn contains a much larger 

 amount of fat than wheat, also a somewhat smaller 

 amount of protein ; the nitrogen- free extract, which is 

 mainly starch, is about the same in amount in both. In- 

 vestigations at the Illinois Experiment Station show that 

 all of the kernels upon the same ear are fairly constant 

 in composition, although the kernels on the tip of the ear 

 have a tendency to contain slightly less protein than those 

 either in the middle or at the base; the differences in both 

 protein and carbohydrates in a few extreme cases was about 

 i per cent. The composition of the kernel is slightly in- 

 fluenced also by the stage of maturity. If, for any rea- 

 son, corn fails to reach full maturity, there is usually a 

 somewhat larger amount of protein and smaller amount 

 of carbohydrates in the dry matter. 



393. Proteids of Corn. The proteids of corn are quite 

 different in character from those of wheat. Small 

 amounts of albumin and globulin are present but the 

 larger portion of the corn proteids is in insoluble forms 

 called zeins, one of which is soluble and the other insol- 



