A Facile Method for the Detection of Aldehydes in Oxidized Lipids Using Solid-Phase Microextraction Fiber and Gas Chromatograph Equipped with a Septum-Free Injector

A facile method is described for the detection of volatile odor components from oxidized lipids. The method is based on headspace selid-phase microextraction(HS-SPME)of the compounds in the vial head space and the subsequent analysis of the volatiles by gas chromatography(GC)using a septum-free sample injector. The extraction was done using a 85 μm carboxen-poly(dimethylsiloxane)SPME fiber and the volatiles were desorbed onto a GC instrument with the septum-free injection port. The septum free injector made it possible to analyze the samples without using a conventional silicone rubber septum, that is easily damaged by the repetitive stubs of a relatively thick blunt needle into the septum and a long desorption time after injection. The method was standardized with authentic C3-C10 aldehydes and was applied to the detection of aldehyde components from oxidized fish oil. Several volatiles, including propanal and hexanal, were clearly separated on a polar capillary column(60m)with reproducible retention times. The present study demonstrates that the method using the GC septum-free injector and the HS-SPME fiber would be useful for the determination of volatile components derived from edible oils.