In-air particle induced X-ray emission elemental and physical trait data of organically produced roasted coffee beans from Ethiopia, Colombia, Honduras, and Mexico

Assessing the physico-elemental traits of coffee beans may assist in determining its nutritional and commercial value as well as geographical origin. Although a number of studies exist describing the physico-chemical traits of coffee, there are no studies describing the physico-elemental profile of organically produced roasted coffee beans. In this study, the levels of trace and toxic metals in organically produced roasted coffee beans from four top coffee production regions (Ethiopia, Colombia, Honduras, and Mexico) that are commercially available in South Africa were compared using in-air particle induced X-ray emission (PIXE). In addition, physical traits of the roasted coffee beans from the selected regions were compared using microscopy. In-air PIXE analysis revealed the presence of P, S, Cl, K, Ca, Ti, Mn, Fe, Cu, Zn, Br, Rb, and Sr in samples. Physical trait data showed that coffee beans from Mexico weighed more than beans from other regions, whilst coffee beans from Honduras had the highest width. In conclusion, physico-elemental analysis using in-air PIXE and microscopy may be promising tools in guiding the nutritional and commercial value as well as geographical origin of coffee.