INFLUENCE OF GRANULATION ON QUALITY OF FLOUR 1] 
injury to the gluten proteins from excessive grinding, and in that 
the viscosity tests showed for the soft red winter wheat middlings a 
slightly progressive impairment of gluten quality and for the hard 
wheat middlings a slightly progressive improvement. As before, no 
loss of glutenin owing to excessive grinding was experienced, neither 
was the water-soluble nitrogen nor the percentage of total protein 
in the washed gluten greatly modified by the treatment the flour 
received. 
The making of washed gluten tests on the excessively ground flours 
presented some difficulties. The most excessively ground samples 
required more water to wet the dough into a homogenous condition. 
Washing the gluten from these samples was exceedingly trying, 
inasmuch as the gluten particles were crumbly, lacked elasticity, 
and were difficult to assemble in one mass. 
QUANTITY AND QUALITY OF THE GLUTEN PROTEIN IN THE 
DIFFERENT-SIZED PARTICLES OF WHICH FLOUR IS NORMALLY 
COMPOSED 
In Table 6 are shown results of the study relative to the quantity 
and quality of the gluten in flour particles of different sizes sifted 
from commercial! flours and from normally reduced middlings stocks. 
The percentage of wet and dry gluten in the various separates 
paralleled the percentage of crude protein very closely, inasmuch 
as the finest particles contained the smallest percentage of both wet 
and dry gluten. If the quality of the gluten is judged from the 
standpoint of water absorbed per gram of dry gluten, the quality 
factor seems to have been fairly constant for all sizes of particles. 
When the viscosity test is applied to equal concentrations of the 
fiour protein, however, the results show fairly conclusively that the 
smaller sized particles contained protein of inferior quality. There 
was some variation, depending upon the nature of the original 
material and the class of wheat from which it was obtained, as to 
which sized particle had the lowest gluten quality; but it is fairly 
safe to state that the particles passing through the 20xx and 25xx 
sieves as a rule contained protein of a quality inferior to that found 
in particles passing through the 12xx and 16xx sieves. The material 
which passed through the 8xx sieve also contained protein of an 
inferior quality. 
Some interesting figures present themselves when the glutenin 
determinations on the various sized particles are considered. With 
the material sieved from the soft red winter wheat middlings stock, 
sample No. 12551, and from the straight grade of soft red winter 
wheat flour, sample No. 12552, there seemed to be a fairly consistent 
reduction in the quantity of glutenin as the size of the flour particle 
decreased. This also was definitely the case with the smaller-sized 
particles sieved from the material represented by samples Nos. 
12550, 12621, and 12620. With the hard wheat first clear flour. 
the glutenin content was found to increase as the size of the flour 
particles decreased. 
The viscosity measurements, with the exception of those made on 
the separates obtained from sample No. 12.618, to a large extent 
paralleled the glutenin determinations. : 
