Extraction and determination of morphine present on the surface of Australian food grade poppy seeds using acidic potassium permanganate chemiluminescence detection

In 2018, the European Food Safety Authority reiterated the need for continued monitoring and reduction of opium alkaloid contamination on culinary poppy seeds. In this study, we propose acidic potassium permanganate chemiluminescence as an alternative detection strategy for the selective determination of morphine on poppy seeds. Six different brands of poppy seed purchased in Australia were found to contain, on average, between 21 and 210 μg/g of morphine. Seeds removed from poppy capsules within the laboratory contained significantly less morphine than those which underwent traditional industrial processing. A high-throughput sensitive flow injection analysis (FIA) method was also developed which provided results in reasonable agreement with a high-performance liquid chromatography – chemiluminescence method and a limit of quantification of 7.1 × 10−4 μg/g. Complex samples encountered in food analyses typically require separation and selectivity in one or more steps of the analytical workflow (such as sample preparation, column separation and/or detection) to improve the confidence in the determination of the target analyte. To this end, the FIA method developed here offers a simple way for industry to rapidly monitor the morphine content of poppy seeds prior to entry into the consumer market.