Department of Analytical Chemistry, University of Valencia, 50 Dr. Moliner St., 46100 Burjassot, Valencia, Spain.
Department of Analytical Chemistry, University of Valencia, 50 Dr. Moliner St., 46100 Burjassot, Valencia, Spain.
Food Chem. 2019 Apr 25;278:373-379. doi: 10.1016/j.foodchem.2018.11.065. Epub 2018 Nov 13.
The present study has exploited the rapidity of the analysis and the multi-elemental capability of the energy dispersive X- ray fluorescence (ED-XRF) technique for the mineral profile determination in cocoa powder. A fast, cheap and environmental sustainable method without reagent consumption or toxic waste generation has been proposed. The samples can be prepared in the form of pellets of 13 mm in diameter and 2-3 mm thickness. The different internal calibrations used by ED-XRF equipment did not provide accurate results when comparing the mineral profile with the concentration obtained by Inductively Couple Plasma Optical Emission Spectroscopy (ICP-OES) after microwave assisted digestion of samples. For direct ED-XRF analysis of the cocoa samples, an external calibration using as standards the cocoa samples diluted with sugar was prepared. The analytical parameters of Relative Standard Deviation and Limit of Detection for the determined elements are adequate to the concentration levels found in the samples.
本研究利用能量色散 X 射线荧光（ED-XRF）技术的快速分析能力和多元素分析能力，对可可粉中的矿物分布进行了测定。提出了一种快速、廉价且环境可持续的方法，无需使用试剂或产生有毒废物。样品可以制成直径为 13mm、厚度为 2-3mm 的颗粒。ED-XRF 设备使用的不同内部校准方法在将矿物分布与通过微波辅助消解样品后电感耦合等离子体发射光谱法（ICP-OES）获得的浓度进行比较时，无法提供准确的结果。对于可可样品的直接 ED-XRF 分析，使用与糖稀释的可可样品作为标准品进行外部校准。对于所测定元素的相对标准偏差和检出限的分析参数足以满足样品中发现的浓度水平。
