Effects of glutelin and lipid oxidation on the physicochemical properties of rice starch

Abstract Background and objectives Starch properties are closely related to the rice quality as starch interacts with other components during rice storage. However, several studies have neglected that the changes in proteins and lipids influence the properties of starch in rice. Herein, we used an artificial climate chest to characterize the effect of glutelin and lipid oxidation on the physicochemical properties of starch during rice storage. Findings Oxidation occurs in glutelin and lipids during the rice storage stage ( p < .01). The oxidation indexes of glutelin and lipids showed the same significant negative correlation in peak viscosity (PV), breakdown (BD), and setback (SB). In contrast, concerning amylose content, final viscosity (FV), and SB, the oxidation of glutelin rather than lipids was more closely related to the changes observed in starch properties ( p < .01). Lipid oxidation significantly correlated with trough viscosity (TV) and amylopectin content than glutelin oxidation ( p < .01). Conclusions All the oxidation indicators of glutelin and lipids were inversely correlated with BD and SB ( p < .01). Carbonyl compound content and fatty acid oxidation were significantly correlated with the physicochemical properties of rice starch. Significance and novelty The physicochemical changes in starch are closely related to the oxidation of glutelin and lipids, which can be used as indicators for assessing rice quality.