Multiple headspace-solid-phase microextraction as a powerful tool for the quantitative determination of volatile radiolysis products in a multilayer food packaging material sterilized with γ-radiation

A method consisting of multiple headspace solid-phase microextraction followed by gas chromatography–mass spectrometry analysis was developed and used to determine the main volatile radiolysis products formed by γ-irradiation of flexible multilayer food packaging samples. The developed method allows the use of solid-phase microextraction in the quantification of compounds from plastic solid samples. A screening of volatiles in the γ-irradiated and non-irradiated films was performed and 29 compounds were identified in the irradiated packaging, 17 of which were absent in the non-irradiated samples. The main volatile radiolysis products identified were: 1,3-di-tert-butylbenzene; 2,6-di-tert-butyl-1,4-benzoquinone; 4-tert-butyl-phenol and the off-odor compounds butanoic acid and valeric acid. These volatile radiolysis compounds were determined with the proposed method and the results are shown and discussed. Solid–liquid extraction and headspace solid-phase microextraction methods were also studied for comparative purposes. The automated solvent-free multiple HSPME technique here presented can be used to quantify the radiolysis compounds in irradiated plastic solid samples in a simple way with the advantages of being free from matrix influence and environmentally friendly.

► We evaluate multiple-HS-SPME as a tool for quantitative determination of radiolites from multilayer packaging materials.
► We identified and quantify the main volatile radiolysis products.
► Problems derived from the use of SPME for analysis of volatiles in solid samples are overcome.