The purpose of this experiment was to determine the concentration of five elements (calcium, iron, magnesium, phosphorus, and potassium) in carob powder and unsweetened Hershey's cocoa powder. The goal was to compare the difference concentrations of trace elements in the carob and cocoa powders to see how they contribute to taste difference. The MDS 2000 microwave digestion 630 watt system was used to digest three samples of each powder. The samples were then diluted to various concentrations and run on the JY ICP atomic emission spectrometer. The samples were run after the standards had been profiled and calibrated. The results of the average of the three carob samples were as follows, in mg/g (±s): Ca=68(± 30), Fe=3.40(±0.1),  Mg=129(±2), P=1.54(±0.03), and K=1030(±65). The results of the one surviving cocoa sample were as follows, again in mg/g: Ca=0.661, Fe=0.059, Mg=1.36, P=7.54, and K=1010. Typical detection limits were (ng/mL) : Ca (4), Fe (1), Mg (1), P (309), and K (56.) Unfortunately many of these results are incompatible with the expected values of each of these powders. More samples would have to be prepared and tested in order for the results to be more significant. 

reviewer note.

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