THE BY-PRODUCTS OF RICE MILLING. 15 
In the calculated analyses given in Tables 8, 10, 12, and 14, for the 
mixed brans as they would ordinarily appear on the market, the ash 
in all cases was 10 per cent or less, the insoluble ash in all cases was 
below 5 per cent, and the fat plus protein ranged from 26.7 per cent 
to nearly 30 per cent. The crude fiber was always above 10 per cent, 
a figure considered by many chemists to be the limit for a pure rice 
bran. The nitrogen -free extract approximated 40 per cent. This 
figure, however, seems to be of little use in determining the char- 
acter of the product, except that in some cases a high figure may 
confirm the presence of a large amount of broken rice. 
The results show that rice polish is characterized by very low acid- 
insoluble ash, by low crude-fiber value, and by high nitrogen-free 
extract. It should have a fat plus protein content above 20 per cent. 
The rice polish in lot D was somewhat abnormal for the reason 
that, on account of the light milling to which the rice had been sub- 
jected, the portion taken off in the brush machine consisted in part of 
the material which usually would be taken off in the second-break 
hullers. 
ALL SAMPLES. 
A consideration of the chemical results on all samples taken shows 
that all the rice hulls examined were very high in both ash and fiber 
and were of such low protein and fat content as to have practically no 
feeding value. In addition, their physical structure renders them 
harmful to animals if fed in too large amounts. 
The stone-reel bran was uniformly much higher in total ash, acid- 
insoluble ash, and crude fiber, and was lower in protein and fat than 
were the huller brans. This was due to the presence of the hulls 
which entered the stone-reel bran after they had been broken up by 
the stones. The analysis of this by-product would indicate that 
usually it contains from 25 to 50 per cent of hulls. The huller brans 
were nearly all very low in fiber and acid-insoluble ash, showing then- 
comparative freedom from hulls, and were high in protein and fat. 
Their composition would make them a very rich feeding stuff if used 
alone. At present, however, huller brans are not used for feeding 
purposes, partly for the reason that they do not keep well and partly 
because millers always have made a practice of including the product 
of the stone reel in their bran. This mixture is the bran as com- 
monly found on the market and contains an amount of hulls from the 
stone-reel bran which would seem to add materially to the keeping 
qualities of the product, and at the same time to give a feed acceptable 
to the consumer. This product, when produced under known condi- 
tions that preclude the addition of ground hulls, should contain over 
26 per cent fat plus protein. It should not exceed 13 per cent of 
crude fiber or 5 per cent of ash insoluble in hydrochloric acid. 
