Characterization of Japanese Polished Rice by Stable Hydrogen Isotope Analysis of Total Fatty Acids for Tracing Regional Origin

We determined the delta D values of the total fatty acids of Japanese rice to test the hypothesis that there is a wide variation in the hydrogen isotopic composition (delta D) of the total fatty acids of Japanese rice sourced from different growth areas in Japan and to distinguish the minor differences among these growth areas. The delta D values showed a wide variation ranging from -216 parts per thousand (Hokkaido) to -183 parts per thousand (Okinawa), indicating a good correlation with the corresponding variations for ambient water (r = 0.63) and mean temperature (r = 0.84). These results suggest that the delta D values for the total fatty acids can be representative of the growth environments in Japan.