STARCH. 



49 



°° /^ "o * 



-to 



27 



Starch is insoluble in cold water, but forms with boiling 

 water a paste in whicli all traces of structure are lost. If a 



specimen of starch be gently heated with water upon a glass 

 slide, the granules will be seen to swell at a temperature of 



Q^CX^ 



(S»% 



33 



40°-50° C, and the appearance of stratification will often be- 

 come plainer. The alkalies and mineral acids generally hasten the 



Fis. 26. Starcli-granulcsofwlieat. Fio. 29. Sfarcli-granules of oats. 



Fig. 27. Starcli-gramiles of Indian corn. Fig. 30. Starch-granules of rice. 

 Fig 28. Staroli-granules of barley. Fig. 31. Starch-granules of potato. 



Fig. 32 Starch-granules of Maranta (arrow-root) 

 Fig. 33. Starcb-grauules of Bomarla (Chili arrow-root). 



Fig. 34. Starch-granules of Vicia sativa, var. leucosperma. All the figures of 

 starch are from Berg and Schmidt. 



4 



