Simultaneous Analysis of Epoxidized and Hydroperoxidized Triacylglycerols in Canola Oil and Margarine by LC-MS

Abstract

The progress of lipid oxidation in foods is evaluated by measuring the peroxides and their scission products. However, hydrogen abstraction-independent pathways are not considered by commonly applied methods despite the known reactivity of epoxides toward biomolecules. Herein, a novel liquid chromatography tandem-mass spectrometry method was developed to detect hydroperoxidized and epoxidized triacylglycerols (TAGs) without derivatization or hydrolyzation of food samples. Epoxidized TAGs could be detected in refined canola oil at concentrations of 96.8 ± 2.08 μM, while only 5.77 ± 0.04 μM hydroperoxidized TAGs could be determined. In contrast to canola oil, margarine was more resistant to lipid oxidation since generation of epoxidized TAGs could only be marginally enhanced from 21.7 ± 0.48 to 28.8 ± 0.64 μM in margarine after treatment at 180 °C for 60 min, as also reflected by a peroxide value of 0.80 ± 0.00 mequiv O2/kg, which remained unchanged. The new method allows the assessment of food safety by the simultaneous measurement of hydroperoxidized and epoxidized TAGs without hydrolysis and laborious sample preparation.

Radical Scavenging Activity of Olive Oil Phenolic Antioxidants in Oil or Water Phase during the Oxidation of O/W Emulsions: An Oxidomics Approach

“…It is noteworthy that considering the only hexanal, as usually appears in the literature, as a secondary oxidation marker, would have led to the misleading conclusion that OPAs in the water phase were more effective towards secondary oxidation. The adopted oxidomics approach, instead, allowed to depict a more complete view of the mechanisms of action of these molecules [ 5 , 8 , 11 , 12 ].…”

“…Recently, Decker et al [ 4 ] pointed out various hurdles in predicting the effectiveness of antioxidants in real emulsions: the involvement in non-free radical scavenging reactions, the presence of different types of interfaces, inherent obstacles in studying lipid droplets properties, and varying oxidation kinetics in different droplets. Moreover, several contributions have recently suggested the expansion of traditional analytical patterns to a wider range of oxidation products to better understand oxidative phenomena [ 5 , 6 , 7 ]. Three distinct viewpoints by Paradiso, Villeneuve, and Laguerre discussed the need for a new step to study lipid oxidation in emulsified systems by focusing on different aspects [ 8 , 9 , 10 ].…”

In Vitro Digestion of Grape Seed Oil Inhibits Phospholipid-Regulating Effects of Oxidized Lipids

“…Additionally, the grape seed oil was characterized regarding the single polyphenols via high-resolution LC-MS analysis, the amount of tocopherols via HPLC/UV detection [13], the determination of fatty acids via GC/FID analysis [14] and the peroxide value using titration [15] before and after in vitro digestion.…”

“…Amber glass vials were cleaned according to Grüneis et al [14] to remove all traces of lipids and lipid-oxidation-promoting agents.…”

<i>In vitro</i> toxicity studies of epoxyoleic acid and diepoxylinoleic acid

“…Monoepoxy and diepoxy fatty acids are detected in a wide variety of fat-or oil-containing processed foods, and their mean concentrations ranged from 13 ppm in cooked meat to 687 ppm in dry nuts (Mubiru et al, 2017;Fankhauser-Noti et al, 2006). It has been also reported that the concentrations of epoxides are higher than those of peroxides during the initial lipid oxidation in canola oil and margarine (Grüneis et al, 2019). Dietary epoxy fatty acids can be orally absorbed in healthy humans (Wilson et al, 2002).…”