title: Multielemental determinations in chocolate drink powder using multivariate optimization and ICP OES.
abstract: In this work multivariate experiments were conducted to optimize the operating conditions for inductively coupled plasma optical emission spectrometry (ICP OES) for multielemental determinations in chocolate drink powder. The operating conditions were investigated using a 2(3) central composite design, where the variables studied were radio frequency power, nebulization flow rate, and auxiliary argon flow rate. The effects of these parameters on plasma robustness and on signal to background ratio (SBR) were considered in parallel, allowing the evaluation of robustness and detectability using few and fast experiments to select the best conditions for the determination of the analytes. In this case, the proposed experiments were applied to the optimization of a method aimed at the determination of Al, Ba, Cd, Co, Cr, Cu, Fe, Mg, Mn, Mo, Ni, P, Pb, V, and Zn in chocolate drink powder. The compromise conditions that allowed obtaining a robust and sensitive analytical method were radio frequency power of 1200 W, nebulization flow rate of 0.6 L/min, and auxiliary argon flow rate of 0.3 L/min. Using these conditions, recoveries between 95 and 105% and relative standard deviations lower than 5% were obtained for the majority of the analytes. The proposed method was successfully applied to the analysis of 15 samples of chocolate drink powder. The highest concentrations of metallic species were found in diet and light products.
authors: Institute of Chemistry, University of Campinas, P.O. Box 6154, 13083-970 Campinas, SP, Brazil.
authors: Rafaella Regina Alves
authors: RR
authors: Peixoto
authors: Andrea
authors: A
authors: Oliveira
authors: Solange
authors: S
authors: Cadore
mesh_terms: D001628:Beverages / Q000032:analysis*; D002099:Cacao / Q000737:chemistry*; D005504:Food Analysis / Q000379:methods*; D005511:Food Handling; D015999:Multivariate Analysis; D011208:Powders / Q000032:analysis / Q000737:chemistry; D013053:Spectrophotometry / Q000379:methods*; D014131:Trace Elements / Q000032:analysis*
chemical_list: D011208:Powders; D014131:Trace Elements