22 



BULLETIN 330, U. S. DEPARTMENT OF AGRICULTURE. 



f?/C£ F/VOM /=I/C£ 

 &/GE M/&CS-///VE */ULt£ft5 



£?/C£ F7?0M f?'CE 



E'E/GrtL/NG E/90M 



COWS B£?L/SH 



f?/GE 



Ef?OM 



Tf?L/MBL£ 



the hulled rice is reduced more than three-fourths in the hullers, but 

 through the remainder of the process the reduction is gradual and 

 small. The total loss of fat in scouring is 85 per cent. 



The crude-fiber content of the rice is reduced 88 per cent when 

 the hulls are removed, and 73 per cent of the remainder is lost dur- 

 ing the process of scouring. 



The protein figure rises on the removal of the hulls, as was the case 

 with the fat content. It is especially worthy of notice that only 10 

 per cent of the protein present in the hulled grain is lost in scour <- 

 ing. This has already been explained by the fact that the protein- 

 bearing aleurone layer 

 is not removed during 

 scouring and that the 

 protoplasm which con- 

 tains protein is dis- 

 seminated throughout 

 the starchy portion of 

 the endosperm. 



Approximately 60 

 per cent of the pen- 

 tosan content is re- 

 moved with the hulls, 

 and 32 per cent of 

 the remainder is lost 

 during the process of 

 scouring. 



The loss of the va- 

 rious chemical ingre- 

 dients of rice of the 

 Japan type corre- 

 sponds closely to that 

 given for that of the 

 Honduras type. 



Figures 8 and 9 illustrate the data contained in the averages of 

 Table VII, calculated to.a moisture- free basis. 



Fig. 8. — Diagram showing the effect of modern rice milling 

 machines en the ash, ether-extract, crude-fiber, protein, 

 and pentosan content of rice of the Honduras type. 



MILLED RICE AND ITS BY-PRODUCTS. 



MECHANICAL ANALYSES AND MILL YIELDS. 



The grading devices employed in the modern rice mill permit the 

 milled rice to be separated according to the size of the particles into 

 almost any character of grades desired. Mill and trade practice, 

 however, has outlined roughly six grades of the Honduras type and 

 three grades of the Japan type, based entirely, or nearly so, on the 



