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In this study, oxidation kinetics of linseed oil were investigated after its blending with corn, canola, sesame, and bitter almond oils at different ratios. As determined by the Rancimat method at 353, 373, and 393 K, the oxidative stability index of each type of blended linseed oil was significantly higher than that of pure linseed oil. In addition, a higher oxidative stability was observed in each of the linseed oil samples when blended with 66% corn, canola, sesame, or bitter almond oils, as compared to those blended with 33%. The highest oxidative stability index was obtained in the 66% corn oil blend. In comparison with pure linseed oil, the 66% corn oil blend decreased in its Q10 value from 2.53 to 1.80 and also in its frequency factor from 29,308,932.45 × 107 to 28.64 × 107 h−1. The highest increase in the Gibbs free energy was observed in the 66% corn oil blend. Practical applications: Linseed oil is a rich source of essential polyunsaturated fatty acids and has poor stability against oxidation. The blending of vegetable oils can be regarded as an effective approach for improving their oxidative stability. Blending can enhance the nutritional value of vegetable oils and improve industrial applications in production of shortening and cocoa butter substitute, characterized by lower calories, low or zero‐trans margarines, and cocoa butter equivalents. This study focuses on blending linseed oil with corn, canola, sesame, and bitter almond oils, while highlighting the effects of this blending on the thermal kinetic parameters of linseed oil. The results of this study can help to design functional lipid blends rich in PUFAs with high oxidative stability and, ultimately, assist their utilization in functional food formulations. [ABSTRACT FROM AUTHOR]

The objective of this research is to analyze the kinetic parameters of linseed oil by treating it with pomegranate peel and seeds at 353, 368, and 383 K using Rancimat. There are no significant differences (p < 0.05) between the oxidative stability indices of samples containing pomegranate peel and pomegranate seeds. In addition, the indices pertaining to the oxidative stability of linseed oil increase in value as the concentrations of pomegranate peel and seeds increase. Apart from the pomegranate peel at 0.1% and the quercetin, all other antioxidants are able to reduce the severity of temperature‐related parameters (i.e., temperature coefficient and Q10 values). In addition, these antioxidants are able to form an activated complex with lower levels of thermal energy (by reducing activation energy and enthalpy) but of more structured configuration (by reducing the frequency factor and entropy). A high correlation is found between the Gibbs free‐energy of activation and the oxidative stability index of samples. The most substantial increase in the Gibbs free‐energy of activation occurs by TBHQ, followed by gallic acid, quercetin, and pomegranate peel at 1%. Practical Applications: Linseed oil is characterized by its high amounts of essential polyunsaturated fatty acids (PUFAs). The high PUFA content of linseed oil contributes to its rapid oxidation. Pomegranate peel and seeds are valuable sources of natural antioxidants. Investigating the effect of pomegranate peel and seeds in reducing the dependence of linseed oil oxidation on temperature provides a range of valuable kinetic parameters. Nevertheless, this subject has received little attention so far. There are few published data regarding the effect of natural antioxidants on lipid oxidation by this approach. Accordingly, this study is designed to investigate the oxidation kinetics and mechanisms of linseed oil as manipulated by fruit peel and seeds of pomegranate. The results show that the fruit peel and seeds of pomegranate can improve the oxidative stability of linseed oil and reduce the severity of effects caused by undesirable temperatures that may increase the oxidation rate of linseed oil. [ABSTRACT FROM AUTHOR]