654 MAIZE 



CHAP. A. The Pericarp. 



XIIL (i) The Tip Cap. 



(ii) The Hull. 



B. The Embryo ("Germ "). 



C. The Endosperm. 



(iv) The Horny Gluten, 

 (v) The Horny Starch. 



a. Crown Starch. 



b. Tip Starch. 

 (vi) The White Starch. 



609. Mechanical Separation of the Different Parts for 

 Analysis. — Comparatively pure samples of these six principal 

 parts may be made by the use of a small, sharp knife. Waste 

 will be obtained in the process, consisting of horny gluten, 

 horny starch, and white starch. 



To make the separation, the grains should be first soaked 

 for 15 or 20 minutes in hot water. The tip cap is then easily 

 and completely separated by simply cutting under one edge 

 and then pulling it off. 



The hull is separated without difficulty by peeling it off in 

 strips, using the knife to start the peeling at the tip end where 

 the hull has been broken by removing the tip cap. By taking 

 care, the complete hull can be peeled out of the detit in the 

 grain of dent maize. 



The horny gluten is then more easily distinguished. It 

 will be plainly seen that it covers the whole grain, except, 

 possibly, the exposed part of the embryo. The horny gluten 

 is removed by carefully shaving it off with the knife ; if the 

 pieces have been allowed to dry for some time, the adhering 

 particles of starch can be more easily separated ; in scraping 

 them off, more or less horny gluten will also be scraped off, so 

 that while it is possible thus to obtain a pure, clean sample of 

 the horny gluten, some waste material is also obtained, which 

 consists of the three endosperm substances — horny gluten, 

 horny starch, and white starch. 



With care the embryo can be removed completely ; if any 

 particles of starch adhere to it. they can be easily and com- 

 pletely scraped off. The remaining part of the grain consists 

 only of the horny starch and the white starch ; this is allowed 

 to dry, and is then broken in two, lengthwise. 



