title: Behavior of Malondialdehyde in Oil-in-Water Emulsions.
abstract: The impact of temperature, emulsifier, and protein type on the reactivity of malondialdehyde in oil-in-water emulsions was elucidated. Malondialdehyde recoveries in aqueous buffer, protein solutions, saturated oil, and fully hydrogenated coconut oil-in-water emulsions stabilized by whey proteins or Tween 20 at 4 or 40 °C were compared. At both temperatures, the reactivity of malondialdehyde in aqueous buffer was the same. In protein solutions, malondialdehyde concentrations were reduced further and its decrease was protein-dependent. Similar trends were found for emulsions. Surprisingly, malondialdehyde was very reactive in saturated oil because only 15% was recovered at 40 °C. However, the degradation in oil proved to be strongly temperature-dependent; at 4 °C, losses amounted to only 8%. This study revealed that malondialdehyde is a very reactive molecule, both in the presence and absence of proteins. Its use as a general oxidation marker should therefore be considered with care.
authors.affiliation: NutriFOODchem Unit, Department of Food Safety and Food Quality (Partner in Food2Know), Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, B-9000 Ghent, Belgium.
authors.forename: Angelique
authors.initials: A
authors.lastname: Vandemoortele
authors.affiliation: NutriFOODchem Unit, Department of Food Safety and Food Quality (Partner in Food2Know), Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, B-9000 Ghent, Belgium.
authors.forename: Bruno
authors.initials: B
authors.lastname: De Meulenaer
mesh_terms: D004655:Emulsions / Q000737:chemistry; D008315:Malondialdehyde / Q000737:chemistry*; D010938:Plant Oils / Q000737:chemistry*; D011506:Proteins / Q000737:chemistry; D014867:Water / Q000737:chemistry*
chemical_list: D004655:Emulsions; D010938:Plant Oils; D011506:Proteins; D014867:Water; D008315:Malondialdehyde
keywords: food proteins; malondialdehyde; oil-in-water emulsions; oxidation marker; reactivity