Quantitative determination of ethoxyquin in apples by gas chromatography

Abstract

Ethoxyquin is extracted from an apple homogenate with hexane and distributed in an acidic aqueous phase. After treatment with sodium hydroxide solution, ethoxyquin is taken up in hexane and mixed with heptafluorobutyric anhydride. The heptafluorobutyryl derivative so formed is analysed by gas chromatography using an electron-capture detector with tetrahydroquinoline as an internal standard. The lower limit of detection for ethoxyquin is 0.02 ng.