Evaluation of the Mechanisms of Mayonnaise Phospholipid Oxidation.

Mayonnaise, which is widely used in foods, is rich in lipids and therefore susceptible to oxidation during the manufacturing process, which can result in loss of quality. Herein, we detected and analyzed phosphatidylcholine hydroperoxide (PCOOH) isomers present in fresh mayonnaise using LC-MS/MS. The PCOOH isomer composition suggests that mayonnaise phospholipid peroxidation is predominantly initiated by radical-oxidation (i.e. upon autoxidation), rather than singlet oxygen-oxidation (e.g. upon light exposure), during manufacturing, packaging and/or storage. This LC-MS/MS method will be useful for elucidating the cause of lipid peroxidation in mayonnaise and related foods. Such information will be valuable to ensure maintenance of product quality.