STARCHES. 



71 



WHEAT starch is obtained from several species of Triticum. 



t consists of large rounded grains and numerous small ones.* 



Hilum and striations are seldom visible. The grains are oval 



or concavo-convex in shape. Wheat starch is also used as 



adulterant. 



RICE starch comes from Oryza sativa, and may be examined 

 after soaking for three hours or more in water. The grains are 



Fig. 43. Starches. 



I, Wheat; II, Potato ; III, Arrow-root ; IV, Corn ; V, Oat ; VI, Rice ; VII, Bean; 

 VIII, Curcuma ; IX, Tapioca ; X, Sago ; XI, Sarsaparilla ; XII, Euphorbia. 



very small and angular, with no hilum. The small grains 

 result from the breaking apart of larger compound oval grains, 

 some of which may be present in the mount. 



OAT starch from Avena sativa resembles rice starch very 

 much. Some of the granules are rounded, semi-circular or 

 lemon-shaped, which helps to distinguish it from rice starch 

 (Fig. 43, V and VI). 



