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Solid phase microextraction-gas chromatography for quantifying headspace hexanal above freeze-dried chicken myofibrils.

Carolyn F Goodridge·Randolph M Beaudry·James J Pestka·Denise M Smith
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Abstract

A method using solid phase microextraction (SPME) combined with gas chromatography/mass spectrometry (GC/MS) was developed and used to determine the oxidation of freeze-dried chicken myofibrils spiked with methyl linoleate. Freeze-dried chicken myofibrils were found to act as a significant reservoir for hexanal. Recovery of hexanal emissions from the headspace above spiked myofibrils was 95% using a 5 min sampling time, with a total analysis time of approximately 12 min/sample. The SPME-GC/MS working linear response was from 0.01 to 10 mg hexanal/L (r( 2) = 0.995). Freeze-dried chicken myofibrils with added methyl linoleate (0.6 mmol/g of protein) were stored at 50 degrees C at water activities of 0.30 and 0.75 for 0, 12, 27, and 50 h. Lipid oxidation was determined using SPME-GC/MS to measure headspace hexanal concentration, the thiobarbituric acid reactive substances assay (TBARS) to quantify malonaldehyde, and a conjugated diene assay. Lipid oxidation was influenced by storage time and water activity. A strong correlation (r = 0.938) existed between SPME-GC/MS and TBARS. The use of SPME-GC/MS was a sensitive and rapid method for detecting hexanal as an indicator of lipid oxidation in chicken myofibrils.

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AldehydesAnimalsChickensChromatography, GasFreeze DryingGas Chromatography-Mass SpectrometryLinoleic AcidsLipid PeroxidationMyofibrilsThiobarbituric Acid Reactive SubstancesJournal ArticleResearch Support, Non-U.S. Gov't

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Carolyn F Goodridge, Randolph M Beaudry, James J Pestka, Denise M Smith. 2003-07-16. Solid phase microextraction-gas chromatography for quantifying headspace hexanal above freeze-dried chicken myofibrils.. https://doi.org/10.1021/jf0260646

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