Thermal oxidation stability of different multi-element oleogels via 1H NMR spectroscopy.

ABSTRACT

In this study, 1H nuclear magnetic resonance was used to track the evolution of oxidation products of different multi-element oleogels (DMEOs) during temperature-accelerated oxidative degradation. The nutritional properties of the DMEOs were also indirectly explored. Oleogels prepared using sitosterol/lecithin oleogelator showed higher nutritional properties than those prepared using carnauba wax or ethyl cellulose oleogelators. Only a small amount of primary oxidation product hydroxide, (Z,E)-conjugated dienic systems, and (E,E)-conjugated dienic systems were produced from all oleogels upon accelerated oxidation. Furthermore, no 1H signal peaks of secondary oxidation products, such as aldehydes or ketones, were detected. However, very small amounts of primary alcohols (-CH2OH-), secondary alcohols (-CHOH-), and epoxides were identified. Moreover, resveratrol loading and surfactant addition effectively stabilized the internal structure and unsaturated fatty acid acyl content of the oleogels.