VARIOUS FACTORY BY-PRODUCTS 187 



In addition to the preceding by-products, a feed called " com- 

 mercial rice bran" is obtained and sold in the South. This is a 

 mixture of the pure bran with varying amounts of hulls, the quantity 

 of the latter being sometimes as high as 50 per cent. According 

 to the Texas station, 7 commercial rice bran may contain as low as 

 4 per cent of protein and 2 per cent of fat, and as high as 50 per 

 cent of fiber. An addition of rice hulls decreases the feeding value 

 of bran in proportion to the amount of hulls added. Adulteration 

 of rice bran with hulls has been largely practised by southern 

 mills, and has brought the feed into disrepute. In view of the 

 danger of such adulteration, rice bran should be purchased only of 

 reputable dealers and on guarantees of valuable components and 

 maximum fiber content. It should contain not less than 10 per 

 cent protein and 6 per cent fat, and not more than 20 per cent fiber. 



Pure rice bran and rice polish are both valuable feeds which 

 compare favorably with corn meal in feeding value and may be 

 fed under similar conditions. At the Louisiana station rice bran 

 was used successfully for one-half of the concentrates in rations for 

 horses and mules, and it is also a good cow feed, if fed with high- 

 protein concentrates and before turning rancid. 8 



Rice polish is a highly digestible starchy feed which is used as 

 a feed for dairy cows, fattening steers, horses, and mules; its high 

 price often makes it more expensive under southern conditions than, 

 e.g., cane molasses (p. 192). 



The rice feeds will not keep long before they turn rancid, on 

 account of the unstable character of the oil and the high oil con- 

 tent of these feeds. Rancid rice feeds are not palatable to livestock. 



Test for Rice Hulls. Pure rice bran and rice meal contain considerable 

 fat and are not moistened if placed on the surface of water. When the test 

 is made with rice bran or meal adulterated with hulls, these will soon sink, 

 into the water. 



QUESTIONS 



1. Describe the method of manufacture by which flour-mill feeds are obtained 



as by-products. 



2. What are the differences in composition and relative feeding value of 



wheat, wheat bran, wheat middlings, and red-dog flour ? 



3. What are the common adulterations of wheat feeds, if any? 



4. Describe the by-products obtained in the manufacture of cereal feeds, 



barley, rye and buckwheat flour. 



5. Describe (a) the corn by-products; (&) the rice by-products. 



C. Why are rice hulls a dangerous material to be used for feeding farm 

 animals ? 



7 Bulletin 73. 8 Wisconsin Bulletin 169. 



