Determination of trans-1,3-pentadiene in foods due to the presence of sorbic acid using SPME-GC-MS

Abstract

The concentrations of trans-1,3-pentadiene and sorbic acid in 22 packaged commercial food samples were investigated quantitatively by gas chromatography with mass spectrometry detection in the selective ion monitoring mode (GC-MS-SIM). Gas chromatography olfactometry (GC-O) was utilized to determine detection and odor activity values for trans-1,3-pentadiene and sorbic acid.

Concentration levels of trans-1,3-pentadiene ranged from 5 +/- 0.1 to 4798 +/- 14.6 mg/L on a DB5 column. Ranges for sorbic acid were from 80 +/- 0.1 to 5150 +/- 20.9 mg/L. GC-O results indicated perception of trans-1,3-pentadiene standard at 500 mg/L (gasoline, kerosene odor). Trans-1,3-pentadiene was often masked by other volatile compounds found in the various food matrixes, which eluted at the same time. GC-MS-SIM determined the quantitative analysis of trans-1,3-pentadiene. The compound was not detected in samples that lacked a sorbate preservative.

The presence of trans-1,3-pentadiene in commercial foods was found in samples due to the use of a sorbate preservative. The technique for the estimation of sorbic acid and trans-1,3-pentadiene levels in the examined food samples by external standard method was applied in this study and permitted an analysis useful for the food industry. Using head space SPME and GC-MS-SIM provided a selective and rapid analyses of sorbate and trans-1,3-pentadiene simultaneously in a small amount of sample, with acceptable linearity and repeatability.