Statistical comparison of extraction methods to determine cadmium in cocoa beans

Abstract

Monitoring the concentration of cadmium in cocoa beans is essential due to the potential effect on the health of consumers. This research aims to develop a suitable extraction method for the determination of cadmium in cocoa beans by using three extraction techniques with acidic digestion of the samples: I) Concentrated HNO₃, II) HNO₃-HClO₄ and III) HNO₃- HCl and subsequent cadmium quantification by flame atomic absorption spectroscopy. The analysis of variance of the cadmium concentrations obtained showed that there is a significant difference between the extraction methods applied and that III one is the most efficient to extract cadmium from cocoa beans. Likewise, several performance parameters of the developed method were evaluated, such as precision (repeatability and intermediate precision), linearity, quantification limit, confidence limit, working range, which allowed to show that the cadmium results obtained by the developed method are reliable and fit for the purpose.