Changes in Total Polar Compounds, Peroxide Value, Total Phenols and Antioxidant Activity of Various Oils Used in Deep Fat Frying

Abstract

In this study, the effect of deep fat frying on oil degradation, total phenols (TP) and total antioxidant activity (TAA) of hazelnut, corn, soybean and olive oils were investigated. Oil degradation and oxidation were monitored by measuring the total polar compounds (TPC) and the peroxide value (PV). The amount of TPC in corn, soybean and olive oils increased significantly with the time increment (p \ 0.05). The PV of the oils did not exceed the maximum acceptable limit of 10 mequiv O 2 /kg after 125 min frying except for hazelnut oil (10.64 mequiv O 2 / kg). Deep-fat frying did not cause any significant change in the TP of corn oil, soybean oil and olive oil (p \ 0.05). A significant decrease in the antioxidant activity was observed after 50 min frying using hazelnut oil and corn oil (p \ 0.05). However, the antioxidant activity of soybean oil and olive oil significantly decreased after 75 and 25 min frying, respectively.

Bioactive compounds of the lipid fractions of agro-industrial waste

“…Different solvents, such as toluene, methanol, ethanol, n-hexane, chloroform, acetone, petroleum ether, and ethyl acetate, may be involved in the reaction. Besides that, the results can be expressed in several different forms: percentage of oxidation inhibition, antiradical efficiency, efficient concentration, Trolox equivalents, tocopherol equivalent, and percentage (Karakaya & Simsek, 2011;Passos, Silva, Da Silva, Coimbra, & Silva, 2010;Pérez-Jiménez & Saura-Calixto, 2006). Therefore, the lack of standardization for the tests causes differences in analytical protocols, which limit comparison possibilities among samples, due to different values of antioxidant capacity.…”

Effects of frying on polar material and free fatty acids in soybean oils

“…Polar material (PM), acid value (AV) and trans fatty acids also form during the frying process (Manral et al, 2008). However, the total PM content of olive oil, corn oil, soybean oil and sunflower oil tends to significantly increase after frying (P < 0.05; Romero et al, 2006;Librelotto et al, 2008;Karakaya & Simsek, 2010). However, the total PM content of olive oil, corn oil, soybean oil and sunflower oil tends to significantly increase after frying (P < 0.05; Romero et al, 2006;Librelotto et al, 2008;Karakaya & Simsek, 2010).…”

Effect of Polar and Non‐Polar Compounds from Oxidized Oils on Oxidative Stability in Corn Oil

“…By comparing the contents of FRSs and oxidized lipids or RSOLs, the degree of oxidation or quality of frying oils can be predicted. [20][21][22] However, the APB value can predict the balance of FRSs and the contents of oxidized products simultaneously, which is a unique capability of this parameter. Values of APB higher than 1.0 imply that the content of FRSs is predominant, whereas those lower than 0.5 suggest that the content of FRSs is much lower than the content of RSOLs such as TPMs.…”