Studies on Fluorine and Other Related Material in the Rice : PartII. The fluorine contents of upland unpolished rice, lowland glutinous unpolished rice, unpolished rice for sake brewing and polished rice,

Abstract

(1) The fluorine contents of 171 samples of lowland glutinous unpolished rice varied from 9.00-69.00_ppm and averaged 22.947_ppm. (2) Analysis of upland nonglutinous unpolished rice showed fluorine in 3.00-25.55_ppm and upland glutinous unpolished rice contained from 10.00-42.33_ppm. On the other hand 9.673_ppm of fluorine were found in polished rice samples. (3) From these figures now obtained it was found that lowland rice had more fluorine than upland rice and that glutinous rice contained more fluorine than nonglutinous. (4) With the deterioration of quality the fluorine contents of rice samples varied to the smaller ones. (5) Nineteen samples of imported polished rice had the fluorine contents of 14.11_ppm (non-glutinous short-grain rice produced in Australia)-115.84_ppm (non-glutinous short-grain rice produced in Formosa).