Determination of Ca, Fe, K, Mg and Zn in pequi fruits (Caryocar brasiliense Camb.) using Inductively Coupled Plasma Optical Emission Spectrometry

摘要

In this work was determined the concentrations of Ca, Fe, K, Mg and Zn in pulp and almond of pequifruits (Caryocar brasiliense Camb.), collected in fairs in the municipalities of Caetité, Guanambi andJacaraci, Bahia by inductively coupled plasma optical emission spectrometry (ICP OES). Initiallystudies were performed to optimize the instrumental parameters of the ICP OES: RF Power (1000-1500W), nebulizer gas flow (0.5 to 1.0 L min-1) and auxiliary gas flow (0.5 and 1.0 L min-1). Optimumvalues were obtained at 1300 W, 0.70 L min-1 and 0.80 L min-1, respectively. Approximately 0,1000 gof samples were digested in microwave oven with the addition of 1.5 ml of concentrated nitric acid and0.5 ml of hydrogen peroxide 30% (v/v), completed to 25 ml final volume and analyzed by ICP OES.The concentrations ranges for the elements in this study were: 1709.1 to 2453.2 mg g-1 for Ca, from5.51 to 36.4 mg g-1 for Fe, from 684.3 to 1845.4 mg g-1 to K, 448.9 to 511.7 mg g-1 for Mg and 54.9 to133.7 mg g-1 for Zn.