MOISTURE IN WHEAT AND MILL PRODUCTS. fi 
DISTRIBUTION OF MOISTURE IN THE TEMPERED WHEAT KERNEL. 
An examination of the data of part 2 of Table II shows that as the 
process of milling progressed from the breaks to the sizings and 
middlings reductions, and then to the tailings and low grade reduc- 
tions, the moisture content of the streams of stock on the various 
rolls became less and less. Figure 1, which gives a graphic representa- 
tion of the relative amounts of moisture present at the successive 
steps in the millmg process indicated in this part of the table, 
illustrates this fact more clearly. The curves shown in this figure 
represent, for each mill, the differences in the moisture content of 
the various streams of roll stock before grinding. 
An interesting point to note in this connection is that the moisture 
content of the second, third, and fourth break streams in the instance 
of mills Nos. 2 and 3 was higher than that of the wheat on the first 
break roll. In the part of the milling process known as the break 
reductions, there is a gradual reduction of the wheat kernel resulting 
in a more or less complete separation of the middlings or endosperm 
particles from the bran. This fact, considered in connection with the 
point mentioned above, leads to the conclusion that for the cases 
examined, very little of the water added in tempering penetrated 
farther than the outer coatings of the kernel. 
It is a well-known fact that fifth and sixth break streams are 
composed of a greater percentage of bran than the preceding breaks, 
and in accordance with the conclusion just stated, should contain a 
correspondingly higher percentage of moisture. The results shown 
here, however, are of a contradictory nature. ‘The probable explana- 
tion of this apparent inconsistency is that the loss of moisture through 
evaporation at the time of grinding and bolting exceeded any increase 
in the moisture content of such streams caused by the elimination of 
drier particles. * 
It is observed also that the roll streams containing the lesser 
amounts of moisture were those known as the low grades, which 
streams occur at the extreme end of the milling process. This low- 
grade stock is composed of very small bran and germ particles 
together with such endosperm particles as are unavoidably removed 
with them when the former are separated from the various streams of 
reduced middlings. The probable reason for their lesser moisture 
content is the fact that the parts of the kernel composing these 
streams are subjected to the grinding action of the rolls a greater 
number of times and, consequently, are exposed to the drying effect 
of the atmosphere much more than those composing the other streams. 
An interesting observation in connection with the data given in 
parts 1 and 2 of Table II is that, in spite of the relatively great differ- 
ence among the mills in the moisture content of the wheat at the 
