Retention effects of oxidized polyphenols during analytical extraction of phenolic compounds of virgin olive oil

Abstract

The hydrophilic extract of virgin olive oil contains several phenolic compounds such as simple phenols, lignans, and secoiridoids that have been widely studied in recent years. Interest in the hydrophilic extract has also been extended to the fraction of oxidized phenols that form during storage as a consequence of oxidative stress. The present investigation compares the two most commonly used extraction methods, namely liquid-liquid extraction and SPE, on fresh virgin olive oil and that kept at different temperatures in the presence of oxygen to promote the formation of oxidative products. The selective retention of these natural and oxidized phenolic compounds in relation to the extraction method was assessed. Quantification of eight identified phenolic molecules and 11 unknown peaks was performed by HPLC-DAD/MSD.

Microwave heating of different commercial categories of olive oil: Part I. Effect on chemical oxidative stability indices and phenolic compounds

“…5. Partial identification was achieved by comparing their retention times with those of the oxidised phenols previously found after conventional oven treatment at 180°C (Carrasco-Pancorbo , 2007), as well as after storage at 50°C for several months (Armaforte et al, 2007). However, due to their low presence level, it was not possible to obtain neat mass spectra that confirmed their identification.…”

“…This is probably due to its high thermo-lability, as previously observed in oven heating at 180°C (Carrasco-Pancorbo et al, 2007). Armaforte et al, 2007). For peak identification see Fig.…”

Phenolic Molecules in Virgin Olive Oils: a Survey of Their Sensory Properties, Health Effects, Antioxidant Activity and Analytical Methods. An Overview of the Last Decade Alessandra

“…Five oxidation phenols were identified with gas-chromatography. Armaforte et al [125] showed that SPE procedure (usually used to extract the phenolic fraction from VOO) may be a not appropriate analytical step when VOO contains significant polar oxidation products (from phenols or lipids); in fact, these latter compounds could interfere with the retention mechanism of phenols during their extraction. These authors also proposed an index to establish the degree of freshness of VOO.…”

Rapid evaluation of oxidised fatty acid concentration in virgin olive oil using Fourier-transform infrared spectroscopy and multiple linear regression

“…Rovellini, Cortesi, and Fedeli (1998) have proposed a method to evaluate the oxidation status of VOOs using RP-HPLC analysis of OFAs. This method has been used in various areas of applied research for VOO (Armaforte et al, 2007;Bendini et al, 2006;Rovellini & Cortesi, 2004) as well as for the analysis of lipid extracts from other matrices (Verardo et al, 2009).…”