Stability to oxidation and interfacial behavior at the air/water interface of minimally-processed versus processed walnut oil-bodies

Jeanne Kergomard (1, 2, 3) , Gilles Paboeuf (1, 4) , Nathalie Barouh (3) , Pierre Villeneuve (3) , Olivier Schafer (5) , Tim Wooster (5) , Claire Bourlieu-Lacanal (2) , V. Vié (1, 4)

1 IPR - Institut de Physique de Rennes
2 UMR IATE - Ingénierie des Agro-polymères et Technologies Émergentes
3 UMR QualiSud - Démarche intégrée pour l'obtention d'aliments de qualité
4 ScanMAT - Synthèse Caractérisation Analyse de la Matière
5 Nestlé Institute of Health Sciences SA [Lausanne, Switzerland]

Oil bodies (OB), the form of triacylglycerol storage in seeds, are interesting natural assemblies for nutritional applications. In walnuts, OB contain an important amount of polyunsaturated fatty acids that could be interesting food ingredients but may be prone to oxidation. The oxidative and interfacial behavior of walnut OB, either minimally-processed or after processing, were compared with processed complex walnut juice. The good oxidative stability of minimally-processed OB over 10 days (PV ≤ 8.4 meq O2/kg, TBARS = 1.4 mmol eq MDA/kg) and of processed walnut complex matrixes over 20 days (PV ≤ 4.8 meq O2/kg, TBARS = 1.4 mmol eq MDA/kg) was evidenced. In comparison, processing of OB promoted their oxidation. The interfacial studies led to the proposition of a new model of adsorption for minimally-processed OB that will be useful to design functional emulsion or foam in which OB act as emulsifiers.

Mots clés: Walnut beverage emulsion; Oil bodies; Oxidative stability; Ellipsometry; Minimalist processes

Domaines: Physique [physics]; Matière Condensée [cond-mat]; Biochimie, Biologie Moléculaire; Alimentation et Nutrition; Biophysique [physics.bio-ph]

Jeanne Kergomard, Gilles Paboeuf, Nathalie Barouh, Pierre Villeneuve, Olivier Schafer, et al.. Stability to oxidation and interfacial behavior at the air/water interface of minimally-processed versus processed walnut oil-bodies. Food Chemistry, 2021, 360, pp.129880. ⟨10.1016/j.foodchem.2021.129880⟩. ⟨hal-03224107⟩