EXPERIMENT STATION RECORD. 



Vol. 43. Abstract Number. No. C. 



RECENT V/ORK IN AGRICULTURAL SCIENCE. 



AGRICULTURAL CHEMISTRY— AGRCTECHNY. 



Effort of premature freezing on composition of wheat, I\I. J. Br.isii {Jour. 

 Ayr. h'cscarrh [U. .S'.], ID il'J20), Xo. J,, pp. iSi-iSS). —Tliis paper, from the 

 Montana Experiment Station, presents the results of an investif,''ation of tlie 

 effects of premature freezing on the more important chemical constituents of 

 the wheat kernel, particularly the nitrogen compounds from which the gluten 

 is formed. 



In order to obtain samples of sound and frozen wheat of the same varieties 

 and grown as iiearlj' as possible under the same conditions, plats were seeded 

 at intervals of a week for about two months, the wheat in all the plats being 

 cut shortly after maturity or innnedlately after the first killing frost. A 

 series of samples was obtained in 1917 and 1918. The wheat from the 1917 

 series was brought to the granary shortly after cutting, thrashed when dry 

 enough to permit, and stored in a room where the temperature was abnormally 

 high. The wheat from the 1918 series was allov>ed to remain in the field 

 through the winter, after being cut and shocked, the grain being thus subjected 

 to severe weathering. The chemical analyses of the grain from the two series 

 indicated a very appreciable effect on the biological properties aside from the 

 effects of freezing. This was noted principally in a higher a-amino and amid 

 nitrogen content in mature samples of the 1918 series than in corresponding 

 samples of the 1917 series. 



The frozen wheat in each series was found to contain larger amounts of 

 nonprotein nitrogen, reducing sugars, and acid-reacting constituents than the 

 sound wheat of tlie same series. The a-amino acid fraction of tlie nonprotein 

 nitrogen was also considerably higher in the frozen than in the sound wheat. 

 In the most severely frozen sample of the 1917 series nine times as much of 

 the total nitrogen of the wheat was in the a-amino form as in the sample which 

 matured earliest. 



The effect of these factors on the milling and bread-making value of wheat 

 is to be considered in a later publication. 



Influence of fermentation on the starch content of experimental sihige, 

 A. W. Dox and L. Yodkr (Jovr. Agr. Research [IJ. S.], 19 {1020), Xo. J/, pp. 

 nS-179). — This contril)ution from the Iowa Experiment Station supplements 

 previous studies on the chemical changes occuring during the fermentation of 

 corn silage (E. S. K., 29, p. 712) by an investigation of possible changes occur- 

 ^3 ring in the starch of the corn during fermentation. Normal experimental corn 

 • silage at various stages of fermentation was examined for total acidity, alcoliol, 

 total sugar, and starch. Qualitative tests were also made for soluble starch 

 and dextrius. The results obtained are summarized as follows: 



501 



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