2 68 MAIZE 



CHAP. Shape of Grain A rather narrow, wedge-shaped grain 



V1, gives a larger percentage of embryo to endosperm than a very 

 broad shallow grain, and for some classes of trade the embryo is 

 of more value than the starchy endosperm. But wedge-shaped 

 grains should not have narrow tips. 



Thickness of Grain. — A thick grain contains more starch 

 in proportion to " hull " or " bran " than a thin one, and is there- 

 fore preferred for certain classes of manufacture. 



Uniformity in thickness, in shape, and in depth of grain, 

 improve the quality ; these can be secured by good breeding. 



Purity of Colour. — White grain must be at least 98 per 

 cent white, and yellow grain 95 per cent yellow ; all else is 

 classed as "mixed". This applies to bulk shelled grain only. 



Shade. — White grain should be pure white, free from 

 black tips and brown blotches ; cut for brownish tinge ac- 

 quired in sun-drying. Yellow grain should be clear, deep 

 yellow, and uniform in colour. 



Colour of Cob. — White grain should not have red tips, 

 which spoil the colour for certain manufacturing purposes ; 

 yellow grain should have white tips in Golden King, Austin 

 Colossal, German Yellow, Yellow Horsetooth, and the standard 

 yellow flint breeds. 



Weight per Unit Measure — This is usually given in 

 standard bushels. The American Standard in all but two 

 States is 56 lbs. of shelled grain. Although in South Africa 

 grain is not sold by measure, it is desirable to take the weights 

 per unit of measure, as samples vary greatly, and the weight 

 gives some indication of quality and chemical composition, 

 for the richer the grain in protein the heavier it usually is. 



Chemical Composition — The character of the endosperm 

 can be determined to some extent by holding the grain to the 

 light and by cutting it longitudinally parallel with the broad 

 axis ; the larger the amount of translucent horny starch the 

 richer in protein. Inasmuch as most of the oil-content of the 

 maize-grain occurs in the embryo a large embryo usually in- 

 dicates a high oil-content. 



Dryness — Dry grain should not (on the High-veld) con- 

 tain more than 12 per cent moisture. A parcel containing 

 not more than 12 per cent will travel safely from South 

 Africa to Europe. 



