Lipid oxidation product nonenal and myoglobin oxidation

Summary Provocative studies have proposed that the common 9 carbon lipid oxidation product, 4‐hydroxy‐2‐nonenal (HNE), increases myoglobin (Mb) autoxidation. Oxidised Mb (Fe 3+ Mb or metMb) formation leads to an unappealing meat discoloration. Since Mb also facilitates lipid oxidation, an HNE induced increase in Mb autoxidation would constitute a positive feedback loop. However, NMR studies have noted that only fatty acids with carbon chain length exceeding 10 can significantly bind to Mb. They predict that HNE should not interact with Mb. The present study has used optical and NMR spectroscopy methods to determine if HNE interacts with Mb and if that interaction leads to an increased oxidation of Mb. The study finds no convincing evidence that HNE interacts with Mb and accelerates Mb autoxidation or oxidation by electron transfer. However, the presence of ethanol in the solution will increase Mb oxidation.