A comparison of solid-phase microextraction (SPME) fibres for measurement of hexanal and pentanal in cooked turkey

Static headspace solid-phase microextraction (SPME) was evaluated for the quantitative measurement of hexanal in cooked turkey samples. Three fibre materials Carboxen/PDMS, PDMS/DVB and Carbowax/DVB with fibre thickness of 75, 65 and 65 μm, respectively, were compared for linearity, limit of detection, and repeatability of response to hexanal in cooked turkey samples. In terms of reproducibility and linearity of response the PDMS/DVB fibre was the most effective of the three fibres studied while Carboxen/PDMS was the most sensitive, with a limit of detection for hexanal of 2 ng/g. The use of 2-methyl pentanal as an internal standard facilitated the accurate measurement of hexanal and pentanal in oxidised turkey homogenates. In fresh and oxidised cooked turkey samples a high correlation between both hexanal and pentanal levels determined by SPME/GC and lipid oxidation measured as 2-thiobarbituric reactive substances (TBARS) was obtained.