Lipid oxidation of brown rice stored at different temperatures

Changes in lipid oxidation and quality of brown rice stored at different temperatures were investigated. Fatty acid value (FAV), peroxide value (POV) and carbonyl value (CV) of brown rice were determined every 45 day for 270 day. Volatile compounds in seven samples stored for 0, 135 and 270 day were also identified. Relationships between volatile compounds and oxidative indices were analysed. Results revealed that the FAV, POV and CV of brown rice significantly increased (P < 0.05) with prolonged storage. Samples stored at low temperatures showed lower FAV, POV and CV than those stored at high temperatures. Brown rice stored under different conditions produced similar volatiles. Based on the principal component analysis of the volatiles, the first two principal components explained 58.20% of the variance. Volatiles of PC1 were correlated with FAV, POV and CV and can be used as an index to assess the quality of stored brown rice.