12 THE PROTEINS OF THE WHEAT KERNEL. 



75 per cent alcohol a specific rotation of 92 . This rotation was so con- 

 stant, not only for the protein from different sorts of wheat from different 

 regions, but also for those from crops of four different years, that it seemed 

 to Kjeldahl that wheat flour contained only one single protein substance 

 soluble in alcohol. 



Fleurent 1 held the view that only one protein substance soluble in alcohol 

 was present in wheat flour, and proposed a method for determining the 

 amount of gliadin and glutenin. By this method he found that gluten con- 

 tained from 60 to 80 per cent of gliadin and 18 to 25 per cent of glutenin, 

 according to the variety of the wheat from which it was obtained. 



Guthrie 2 concluded that the water-absorbing power of wheat flour was 

 greater when the proportion of glutenin to gliadin was greater, strong flours 

 being those relatively rich in glutenin. 



Teller 3 devised methods for determining the relative quantities of the 

 different proteins in wheat flour and applied them to flours of different 

 origin and to various mill products. 



Teller* also concluded that the proteose found by Osborne & Voorhees 

 was gliadin that had been dissolved in small quantity in the aqueous extract. 

 Osborne 5 showed that this was erroneous and gave the reasons why he had 

 not mistaken gliadin for proteose. 



Morishima's 6 investigations led him to believe that wheat gluten contained 

 but a single protein, and that glutenin and gliadin were derivatives of one 

 and the same substance, which he named artolin. 



Teller 7 determined the proportion of the several proteins present in the 

 wheat kernel on many consecutive days during the ripening of the grain 

 and found a large increase of gliadin nitrogen during this period, together 

 with a smaller though marked decrease of the glutenin nitrogen when consid- 

 ered in proportion to the whole amount of nitrogen present. The changes 

 in the proportion of leucosin and globulin nitrogen were less marked and 

 more irregular. 



Ritthausen 8 again asserted his belief in the existence of three distinct 

 proteins in wheat that were soluble in alcohol, but offered no new evidence 

 of their existence. 



1 Fleurent, Comptes rendus de l'Academie des Sciences, 1S96, cxxni, p. 755. 

 7 Guthrie, Agricultural Gazette of New South Wales, September, 1896. 



3 Teller, Arkansas Agr. Exp. Sta. Bull. 42, part 2, p. 81. 1896. 



4 Teller, American Chemical Journal, 1S97, xix, p. 65. 

 6 Osborne, ibid., 1S97, xix, p. 263. 



6 Morishima, Archiv fur experim. Pathologie und Pharmakologie, 1898, xu, p. 34S. 



7 Teller, Arkansas Agr. Exp. Sta. , Bull. 53, p. 53. 1898. 



8 Ritthausen, Journal fur praktische Chemie, 1899, Lix, p. 474. 



