Impact of phosphatidylcholine and phosphatidylethanolamine on the oxidative stability of stripped peanut oil and bulk peanut oil.

Effect of phosphatidylcholine (PC) and phosphatidylethanolamine (PE) on oxidation stability of stripped peanut oil (SPO) and bulk peanut oil (BPO) was investigated by EPR. Impact of commercial lecithin and cephalin on BPO oxidation was also studied. PC < 1000 ppm could not affect SPO oxidation but obviously accelerated oxidation above 1000 ppm. PE acted as antioxidant below 250 ppm, had no effect at 500 and 1000 ppm but behaved prooxidative properties above 2500 ppm. It suggested that there was a threshold value for PC and PE to act as prooxidant in SPO, which above the CMC yet not just at the CMC. PC (500 ppm) and PE (100-500 ppm) decreased BPO oxidation rate through reducing the formation of peroxyl and carbon-centered radicals. 250, 500 ppm PC from lecithin and 100, 250 ppm PE from cephalin possessed antioxidant abilities in BPO during Schaal oven test, demonstrating the results obtained with EPR.