THE BY-PRODUCTS OF RICE MILLING. 5 



Two general plans were 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- 

 ure. 



Ash. 



Ash 

 insolu- 

 ble in 

 10 per 

 cent 

 HC1. 



Ratio of 

 insoluble 



ash to 

 total ash. 



Crude 

 fiber. 



Protein 



(N X 

 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 

 1.0S 

 1.07 

 1.06 

 1.04 

 1.04 

 1.04 

 1.03 

 1.04 

 1 : 1. 05 

 1 : 1. 03 

 1 : 1. 07 

 1 : 1.04 

 1 : 1. 03 

 1 : 1. 06 

 1 : 1. 06 

 1 :1.04 

 1 : 1. 05 

 1 : 1. 06 



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. 

 2.81 

 2.50 

 4.12 

 3.16 

 3.49 

 2.37 

 2.02 

 3.68 

 2.20 

 2.94 

 1.88 

 2.56 

 3.14 

 1.75 

 2.73 

 2.85 

 2.64 

 2.69 

 2.08 

 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 



1 Omitted from summary, as the mill was old and did not make separations properly. 



