The effect of sterols on the oxidation of edible oils

doi:10.1016/0308-8146(83)90030-4

Food Chemistry

Volume 10, Issue 2, February 1983, Pages 141-147

https://doi.org/10.1016/0308-8146(83)90030-4 Get rights and content

Abstract

The effect of sterols on the oxidation of a triglyceride mixture, similar in composition to olive oil, has been studied at 180°C. Δ⁵-Avenasterol and fucosterol are effective as antioxidants, whilst other sterols, including cholesterol and stigmasterol, are ineffective. The antioxidant effect of Δ⁵-avenasterol increases with concentration in the range 0·01% to 0·1%.

An hypothesis is presented to explain the effectiveness of the sterols as antioxidants. It is concluded that lipid free radicals react rapidly with sterols at unhindered allylic carbon atoms. Isomerisation leads to a relatively stable allylic tertiary free radical, which is slow to react further, and this interrupts the autoxidation chain.

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Citation Excerpt :
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^∗: Present address: Department of Food Science, University of Reading, London Road, Reading RG1 5AQ, Great Britain.

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Food Chemistry

Abstract

References (13)

Stereospecific analysis of triglycerides: An analysis of human depot fat

Archs. Biochem. Biophys.

The identification of 28-isofucosterol in the marine green algae Enteromorpha intestinalis and Ulva lactuca

Phytochemistry

Triterpenes and 4α-methylsterols in birch wood

Acta Chem. Scand.

Effect of olive oil hydrocarbons and triterpene alcohols on the stability of heated cotton seed oil

Acta Alimentaria

Changes in the sterol composition of olive oil on heating

J. Sci. Fd. Agric.

Effect of plant sterols on the rate of deterioration of heated oils

J. Sci. Fd. Agric.

Cited by (134)

Thermal oxidation stability of different multi-element oleogels via <sup>1</sup>H NMR spectroscopy

Recent progress in the thermal treatment of oilseeds and oil oxidative stability: A review

Tomato (Solanum lycopersicum L.) seed: A review on bioactives and biomedical activities

Antioxidant interaction of α-tocopherol, γ-oryzanol and phytosterol in rice bran oil

The effects of CO<inf>2</inf>-induced acidification on Tetraselmis biomass production, photophysiology and antioxidant activity: A comparison using batch and continuous culture

Cold pressed sunflower (Helianthus annuus L.) oil