Document Type

Article

Publication Date

12-10-2008

Journal or Book Title

Journal of Agricultural and Food Chemistry

Volume

56

Issue

23

First Page

11424

Last Page

11431

DOI

10.1021/jf8022832

Abstract

Oxidative stability of egg and soy lecithin in emulsion was evaluated with two transition metal ions, cupric and ferric ion, at two concentration levels (50 and 500 μM). The effect of pH on lipid oxidation was also examined under these two concentrations for each ion. Egg lecithin (EL) had similar peroxide value (PV) development pattern as soy lecithin (SL) when treated with cupric ion under both acidic and neutral pH. Acidic pH of 3 accelerated oxidation of both EL and SL, especially under high concentration of copper. When treated with ferric ion, EL oxidized much faster than SL did. EL had higher value of thiobarbituric acid-reactive substances (TBARS) than SL, possibly because of its higher content of long-chain polyunsaturated fatty acids (PUFA). Acidic pH accelerated TBARS development for both EL and SL, but EL had more significantly increased values. Cupric ion was more powerful than ferric in catalyzing oxidation of both EL and SL under both acidic and neutral pH conditions as measured by PV and TBARS. Linoleic acid may contribute to higher PV production, however, arachidonic acid and docosahexaenoic acid may have contributed more to TBARS production. Overall, SL showed better oxidative stability than EL under the experimental conditions. This study also suggests that using multiple methods is necessary in properly evaluating lipid oxidative stability.

Comments

Posted with permission from Journal of Agricultural and Food Chemistry, 56, no. 23 (2008): 11424–11431, doi: 10.1021/jf8022832. Copyright 2008 American Chemical Society.

Copyright Owner

American Chemical Society

Language

en

File Format

application/pdf

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