Effect of an olive phenolic extract on the quality of vegetable oils during frying

• Published in: Food chemistry Vol. 176; pp. 184 - 192
• Main Authors: Esposto, S., Taticchi, A., Di Maio, I., Urbani, S., Veneziani, G., Selvaggini, R., Sordini, B., Servili, M.
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.06.2015
• Subjects: Cooking; Frying; Hot Temperature; Low-molecular-weight aldehydes; Oil thermal degradation; Olive Oil; Olive phenolic extract; Olive vegetation waters; Oxidation-Reduction; Phenolic compounds; Phenols - analysis; Plant Oils - chemistry; Polyphenols - analysis; Tocopherols; Tocopherols - analysis; Oil thermal degradation; Frying; Tocopherols; Phenolic compounds; Olive phenolic extract; Low-molecular-weight aldehydes; Olive vegetation waters
• ISSN: 0308-8146; 1873-7072
• DOI: 10.1016/j.foodchem.2014.12.036

•A phenolic extract (PE) from an olive by-product was used to improve the performance of a frying oil.•PE in frying oil could preserve α-tocopherol against oxidation.•PE in frying oil allowed the reduction of negative volatiles emission.•Oxidative phenolic products might be used as markers of oil alteration.•PE in a refined oil induces the same performance as an expensive extra-virgin olive oil. The potential of a phenolic extract (PE) from olive vegetation water (OVW) to limit the negative effects of frying was tested after adding it at different concentrations to a refined olive oil (RO). Its efficacy was also compared to ROs containing butylated hydroxytoluene (BHT) and an extra virgin olive oil (EVOO) with a high polyphenol content. Analyses of the oils collected after 30min, 1, 2, 4, 6, 8, 10 and 12h of frying at 180°C, demonstrated that degradation of the polyphenols was proportional to the original content; at a concentration of at least 400mg/kg of polyphenols, PE was able to reduce oxidation of the tocopherols and the emission of low-molecular-weight aldehydes better than BHT and with similar results to the EVOO. In addition, secoiridoid oxidative compounds were examined by high-performance liquid chromatography/triple quadrupole tandem mass spectrometry with electrospray ionisation.