THE BY-PRODUCTS OF RICE MILLING. 5 
Two general plans won 4 followed in conducting the study of rice 
by-products discussed in this bulletin. A large number of mills were 
visited and samples of the various by-products were taken both 
before mixing and when ready for market. After the examination 
of these samples had been completed it seemed desirable to obtain 
more detailed information relative to the yield and character of the 
various products under carefully controlled and known conditions, 
and for this purpose special runs were made, during which each part 
of the reduction products was kept separate and was carefully 
weighed and mixed before sampling. 
CHEMICAL COMPOSITION OF BY-PRODUCTS FROM DIFFERENT MILLS. 
In reporting the chemical results on the first part of this investi- 
gation the analyses of similar products from all the mills have been 
grouped together in Tables 1 to 6, as follows: Rice hulls, stone-reel 
brans, huller brans and pearling-cone meals, mixed brans as sold by 
the mill, rice polishes, and miscellaneous samples of interest. In these 
tables each mill has been designated by a letter, so that the various 
products of any one mill may be followed, if desired. 
Table 1. — Analyses of rice hulls. 
Mill. 
Sample No. 
Moist- 
lire. 
Ash. 
Ash 
insolu- 
ble in 
10 per 
cent 
HC1. 
Ratio of 
insoluble 
ash to 
total ash. 
Crude 
fiber. 
Protein 
(NX 
6.25). 
Ether 
extract 
A.. 
25062— L 
B 
25067— L 
c 
25078— L 
D 
25090— L 
E 
25160— L 
F 
25165— L 
G 
25192— L 
I 
i 11976— L 
J 
17059— L 
K 
15311— K 
L 
12655— L 
M 
12643— L 
N... 
12613— L 

12622— L 
P 
11978— K 
Q 
15435— K 
R 
12604— L 
S 
12632— L 
T 
15451— K 
U 
17086— L 
Average 
Per ct. 
5.47. 
6.91 
5.00 
7.19 
8.20 
7.76 
6.44 
7.66 
8.85 
9.25 
9.37 
7.88 
8.28 
6.31 
8.45 
7.97 
9.69 
9.43 
9.38 
8.93 
9.69 
5.00 
7.93 
Per ct. 
18.80 
19.12 
18.04 
17.31 
20.01 
21.43 
21.48 
21. 13 
17.40 
20.59 
22.03 
20.63 
16.40 
20.79 
20.06 
18.14 
17.24 
19.69 
20.81 
21. 35 
22. 03 
16.40 
19.54 
Per ct. 
17.72 
18.22 
16.78 
16.11 
18.84 
20.67 
20.66 
20.24 
16.70 
19.67 
20.98 
19.88 
15.27 
19.97 
19.35 
17.17 
16. 14 
18.90 
19.90 
20.10 
20.98 
15.27 
18.58 
:1.07 
:1.05 
:1.08 
:1.07 
:1.06 
:1.04 
:1.04 
:1.04 
:1.03 
:1.04 
:1.05 
:1.03 
:1.07 
:1.04 
:1.03 
:1.06 
:1.06 
:1.04 
:1.05 
:1.06 
1 : 1. 05 
Per ct. 
46.82 
44.70 
36.57 
46.48 
40.95 
40.96 
41.16 
40.46 
42.50 
39.23 
38. 95 
43.01 
44.29 
39.84 
42.94 
38.62 
41.65 
39.90 
39.39 
36. 57 
46.82 
36.57 
41.29 
Per ct. 
2.02 
3.68 
2.20 
2.94 
1.88 
2.56 
3.14 
1.75 
2.73 
2.85 
2.64 
Z08 
2.52 
4.12 
1.75 
2.66 
Per ct. 
0.64 
1.15 
.68 
1.10 
1.22 
.31 
.36 
4.77 
.77 
.83 
.73 
.67 
1.31 
.53 
.53 
.82 
1.04 
1.17 
.51 
.86 
1.31 
.51 
Omitted from summary, as the mill was old and did not make separations properly. 
