394 



Chemical Constitution of Starch [June-September 



to choose from, a molecule consisting of two, four, eight or twenty 

 amylogen groups. 



Synkiewski points out that in forming amylodextrin only the 

 maitose carbinol bonds were dissolved, the dextrin-carbinol bonds 

 remaining intact. These dextrin-carbinol bonds were also not 

 attacked by malt at 78° C. By a /^-hydrolysis, protodextrin II is 

 formed, in which these linkings persist. By Solution of the a- 

 bonds, maitose is split off and dextrinose is left, in which the dex- 

 trin-carbinol bond remains. Dextrinose is also obtained from pro- 

 todextrin I, which shows that this substance has the bond intact; 

 and, since it comes from amylodextrin, it must have just as many 

 dextrin groups as amylodextrin and therefore just as many as 

 amylogen. From the molecular weight of protodextrin I it follows 

 that it consists of four protodextrin I residues; therefore, the 

 starch molecule is composed of four amylogen residues and its 

 empirical formula must be CsieHgßoOiso- 



For the sake of simplicity, the amylogen residues are repre- 

 sented in triangulär form : 



(C,s) 



/\ 



(Cx8)-(Ci8) 



and the starch molecule may then be represented on a plane surface 

 as follows : 



JCisl 



Fig. 4, 



