RP-UHPLC–DAD-QTOF-MS As a Powerful Tool of Oleuropein and Ligstroside Characterization in Olive-Leaf Extract and Their Contribution to the Improved Performance of Refined Olive-Pomace Oil during Heating

Abstract

Since olive leaf is a potential source of phenolic fraction that is assumed to have good antioxidative effects, we purposed to add its extract to the refined olive-pomace oil during heating to increase its oxidative stability. RP-UHPLC-DAD-QTOF-MS was employed to characterize the phenolic fraction.The oil samples were evaluated by measuring the polymers and the polar compounds and thus detecting specific oxidized compounds. Using this approach, the results showed that incorporating olive leaf extract in refined oil significantly reduced the formation of polymers from 14.39% to 10.45% and the oxidation state by the variation of extinction ΔK from 3.02 to 2.29 during 20 h of heating compared to unenriched oil. This study has proven that the use of natural substances is an opportunity to extend the life of refined oils.

Characterization and Influence of Static In Vitro Digestion on Bioaccessibility of Bioactive Polyphenols from an Olive Leaf Extract

“…Secoiridoids derivates from the structure of tyrosol have also been identified in this extract. A peak ( 33 ) with m / z 523 in EIC was found whose molecular formula corresponds with ligstroside, as well as an ion in EIC m / z 361 with ligstroside aglycone ( 58 ) [ 14 , 19 , 26 , 27 , 28 , 29 , 30 ]. Additionally, an [M-H] − ion with m / z 389 ( 14 ) was assigned as oleoside or secologanoside, both of which have been previously identified in olive.…”

Performance of Olive-Pomace Oils in Discontinuous and Continuous Frying. Comparative Behavior with Sunflower Oils and High-Oleic Sunflower Oils

“…In the same work, they studied changes of volatile profiles of olive-pomace oil at 180 and 220 °C for the first time, as well as in extra virgin olive oil and palm oil. Other publications on the use of olive-pomace oils in frying have focused on improving their stability by adding coconut oil [ 19 , 20 ], squalene [ 21 ] or olive leaf extracts [ 22 ].…”

Antioxidant and Antibacterial Activities of a Purified Polysaccharide Extracted from Ceratonia siliqua L. and Its Involvement in the Enhancement Performance of Whipped Cream

“…Generally, polysaccharides have been increasingly utilized as a substitute for a lower fat content and to provide a greasy texture and a highly appealing sensory quality. The K232 and K270 values indicate the formation of conjugated dienes of polyunsaturated fatty acids and the presence of primary and secondary oxidation products, respectively [25]. Owing to the incorporation of KWSP, a sharp decrease in K232 and K270 was detected for the enriched extracted fat samples.…”

“…In order to infer the influence of KWSP on cream fats, we calculated the coefficients of specific extinction at 232 nm (K232) and 270 nm (K270) with a spectrophotometer (model 35, Beckman Instruments, Inc., Fullerton, CA, USA), adopting Ben Hamouda et al method [25]. A quantity of 0.05 g of fat was added to 25 mL of cyclohexane, so as to measure K232, and 0.25 g, to determine K270.…”