Oxidative Stability and Volatile Formations in Linoleic Acid-D₂O Models in the Presence of Deuteron or Electron Donors

Effects of deuteron (D⁺) and electron donors on the oxidative stability in linoleic acid–water model systems were evaluated by analyzing headspace oxygen content and headspace volatiles. Acetic acid-d and tetrakis(dimethylamino)ethylene (TDAE) were selected as a deuteron and an electron donor, respectively. Samples containing acetic acid-d had significantly lower headspace oxygen content than controls while those containing TDAE had significantly higher headspace oxygen content (p < 0.05). Combination of acetic acid-d and TDAE accelerated the consumption of headspace oxygen. Volatiles including t-2-heptenal, 2-octenal, or 2,4-octadienal had higher mass to charge ratio (m/z) of (molecular weight +1)/molecular weight in samples with deuterium oxide than in samples with deuterium free water. However, no significant difference was observed in the m/z ratio of (molecular weight +1)/molecular weight of those volatiles among samples with or without deuteron or electron donors. Also, lipid hydroperoxides with deuterium, were not found in samples containing deuterium oxide and acetic acid-d. Therefore, added acetic acid-d may not be involved on the formation of lipid hydroperoxides and volatiles directly.