Abstract
In this study, we aimed to investigate changes in the lipid content of brown rice and its composition of fatty acids during long-term storage, both being factors contributing to the characteristic undesirable odor of stored rice. The effect of subsequently polishing the brown rice on these undesirable odor components was also investigated. The lipid content in the brown rice following long-term storage decreased by up to 24.6%, and the quantity of unsaturated fatty acids extracted from the rice bran flour, derived from the outer layer of the rice grains, decreased by up to 11.2%. After a storage period of more than 3 years, the concentrations of ten volatile components in the brown rice increased significantly. However, when the rice was polished to remove the bran layer, leaving 90% of the original grain, the concentration of these undesirable volatile components fell to less than half that in the brown rice.
