Quantitative analysis of residual solvents in food packaging printed films by capillary gas chromatography with multiple headspace extraction

Abstract

A procedure for stepwise gas extraction at equal time intervals has been developed, which is called “multiple headspace extraction” (MHE), because it uses the same equipment as for a standard headspace analysis. The method is suitable as a calibration method for the headspace analysis of volatile trace compounds in solid samples which otherwise cannot be analysed quantitatively. A BASIC program has been used to perform the necessary calculations for quantitative determinations. The application of the MHE procedure is demonstrated on the example of the analysis of residual solvents in printed films which are used as food packaging material, and for the determination of vinyl chloride monomer in a PVC resin. Particularly for the solveny analysis a good glass capillary column is required to separate the complex mixtures which are used for printing the films.