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22 BULLETIN 1463, U. S. DEPARTMENT OF AGRICULTURE 
In factors pertaining to the mixing and handling of the dough, 
the excessive grinding showed: some tendency to slow up the rate 
at which the flour absorbed water and to result in a sticky and weak 
dough. 5; 
The results shown here for this method of excessive grinding agree 
in kind with those obtained by Alsberg and Grifing in their use of 
the ball and flint mill, but the extent of the effect on baking quality 
was not nearly so marked. This leads to the conclusion that the 
amount of excessive grinding necessary to affect seriously the baking 
quality of flour material makes it unlkely that any very marked 
damage would occur in actual milling practice. 
The baking results of the material resulting from the excessive 
grinding done in accordance with method No. 2 previously described, 
are given in Table 12. In these tests, portions of three middlings 
stocks were ground to various degrees of fineness. The method used 
in grinding and sifting each of these portions limited only the maxi- 
mum size and not the minimum size of the particles of the resultant 
materials. | 
Water absorption showed a very marked tendency to increase with 
each increase in degree of fineness of grinding. In the case of the 
hard wheat middlings, the increase in absorption for the material 
ground to the greatest fineness over that of the original material 
was 7.9 per cent for the sponge-dough method of baking, and 9.8 
per cent for the straight-dough method. For the two soft red 
winter wheat middling stocks, which were baked only by the sponge- 
dough method, the increases were less, being 1.2 per cent for each. 
Shollenberger and his coworkers in a similar investigation on hard 
spring wheat middlings obtained the same consistent tendency for 
water absorption to increase as did Alsberg and Grifiing in connec- 
tion with their investigation on hard spring wheat patent flour. 
As might be expected, increases in the weight of loaf were shown 
corresponding to some extent to the increases in the percentage of 
water absorbed. : 
The volume of loaf was not materially affected by this form of 
excessive grinding. The differences shown are too small to be 
significant. 
The color of crumb varied only slightly and showed no consistent 
tendency either to improve or to become worse. Neither did the 
grain of crumb show any tendencies as to direction, although in the 
case of this factor the variations were slightly greater. A similar 
lack of tendency was also apparent in the shade of color of crumb 
and in the color and condition of the crust. 
The time required for proofing increased fairly consistently with 
the increase in fineness. 
In factors pertaining to the mixing and handling of the dough the 
unground hard wheat middlings produced a coarse, rough, lumpy 
dough. This condition, however, was not present in connection with 
the doughs of the ground portions of these middlings or with the 
doughs of the soft red winter wheat middlings. This indicates that 
the coarse particles of the hard wheat middlings were somewhat 
more impervious to water than were the particles of which the other 
samples were composed, notwithstanding the fact that no slowness 
