Elemental Analysis of Brown Rice by Inductively Coupled Plasma Atomic Emission Spectrometry and Instrumental Neutron Activation Analysis

Thai jasmine rice samples were collected from the paddy field in the north and northeast of Thailand. After dehulling, the brown rice samples were determined for the elemental concentrations by inductively coupled plasma atomic emission spectrometry (ICP-AES) and instrumental neutron activation analysis (INAA). The concentrations of Ca, K, Mg, and P were determined by ICP-AES and the concentrations of Fe, Mn, and Zn were analyzed by INAA. The ICP-AES and INAA methods were validated by certified reference materials. The results showed that the methods are reliable to analyze the elemental concentrations in rice samples. The order of the mean concentration of elements was P > K > Mg > Ca >Mn > Zn > Fe. The concentrations of elements ranged from 3,024-3,830 mg kg-1 P, 1,404-1,927 mg kg-1 K, 980-1,284 mg kg-1 Mg, 72-128 mg kg-1 Ca, 21.9-43.8 mg kg-1 Mn, 22.5-32.7 mg kg-1 Zn, and 5.10-9.75 mg kg-1 Fe.