Effect of Chlorophyll on Lipid Oxidation of Rapeseed Oil

The residues of chlorophyll induce oxidative rancidity and deterioration through photo‐oxidation. However, the effect of chlorophyll on the quality of rapeseed oil is still unknown. In this study, chlorophyll is added into rapeseed oil to reach the desired treatment levels of 2, 5, and 10 mg kg −1 , while no chlorophyll is added in the control sample. Dynamic changes of the peroxide value of rapeseed oils with different chlorophyll contents exposed to light and stored in the dark at different times (0, 1, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, and 60 days) are investigated. The results show that the peroxide value of rapeseed oil exposed to light increased significantly, especially for the oil with a high content of chlorophyll. In contrast, the peroxide value of rapeseed oil stored in the dark is nearly unchanged no matter whether extra chlorophyll is added. This study shows that chlorophyll in rapeseed oil can trigger oil oxidation, and therefore it is necessary to take measures to reduce the chlorophyll content in rapeseed oil or store rapeseed oil in the dark as soon as possible. Practical Applications : This study shows that chlorophyll in rapeseed oil can trigger oil oxidation, and therefore it is necessary to take measures to reduce the chlorophyll content in rapeseed oil. In this study, dynamic changes of peroxide values of rapeseed oils with different chlorophyll contents exposed to light and stored in the dark at different times are investigated. The results show that the peroxide value of rapeseed oil exposed to light increases significantly, especially for the rapeseed oil with a high content of chlorophyll. In conclusion, chlorophyll in rapeseed oil can trigger oil oxidation.Therefore, it is necessary to take measures to reduce the chlorophyll content in rapeseed oil or store rapeseed oil in the dark as soon as possible.