6o 



THE PROTEINS OF THE WHEAT KERNEL. 



Thirty grams of preparation 77 were then dissolved in alcohol of 0.90 sp. gr. , 

 and the clear solution evaporated to small volume, cooled, and, as no protein 

 separated, strong alcohol was added until a considerable precipitate resulted, 

 equal to about one-half the dissolved protein. This precipitate, which, if 

 the extracted protein were a mixture, as stated by Ritthausen, would con- 

 tain the bulk of the substances insoluble in strong alcohol, weighed 12 grams. 

 This was marked preparation 78. 



The solution from which this substance had separated must have con- 

 tained the chief part of the protein called by Ritthausen gluten-fibrin. It 

 was then concentrated to small volume, cooled, water added until a con- 

 siderable precipitate resulted, the solution then heated until all dissolved, 

 and, after cooling, the mother-liquor was decanted from the separated 

 protein. This process was repeated four times, and the precipitate finally 

 obtained dehydrated with absolute alcohol and digested with ether. This 

 preparation, 79, weighed 1.6 grams. 



Preparations 77, 78, and 79. 



It is clear from these analyses that no separation into proteins of differing 

 composition had thus been effected. 



EXTRACTION OF "SHORTS" WITH DILUTE ALCOHOI,. 



Two kilograms of ' ' shorts ' ' from the spring- wheat flour were extracted 

 with alcohol of 0.90 sp. gr. and the extract squeezed out with a screw- press. 

 The extract, which was a deep red-brown in color, was filtered perfectly 

 clear, and then concentrated by distillation to about one-third. On cooling, 

 the protein separated, leaving the mother-liquor as a deep coffee-brown 

 liquid. This was decanted, the precipitate dissolved in alcohol of 0.90 

 sp. gr. , and again precipitated by concentration and cooling ; the strongly 



