Department of Analytical Chemistry, Faculty of Sciences/I.U. CINQUIMA, Campus Miguel Delibes, University of Valladolid, Paseo de Belén 7, 47011 Valladolid, Spain.
Food Chem. 2014;152:81-7. doi: 10.1016/j.foodchem.2013.11.134. Epub 2013 Nov 28.
An original method to determine the food additive calcium disodium ethylenediaminetetraacetate in bottled food is proposed. The method involves the solid-liquid extraction of a portion of the whole content of legume or artichoke bottles, or the dilution of sauce samples, with water followed by an evaporation step by heating. Finally, ethylenediaminetetraacetic acid is methylated and determined by GC. Recoveries obtained on spiked samples were acceptable (96-108%) with RSDs comprised from 4.3% to 10%. Results suggest that the determination of additive only in the liquid phase of legume or artichoke bottles is not suitable to know its total amount because the additive is distributed between the liquid and solid phases. The contribution of each step of the analytical method to the uncertainty of the measured concentration has been assessed by a "bottom-up" approach, including the heterogeneity of the sample which resulted to be very variable after studying twenty samples.
提出了一种测定瓶装食品中添加剂乙二胺四乙酸二钠钙的新方法。该方法包括对豆类或朝鲜蓟瓶的全部内容物的一部分进行固液提取，或对酱汁样品进行稀释，然后用水加热蒸发。最后，乙二胺四乙酸进行甲基化，并用 GC 测定。加标样品的回收率（96-108%）可接受，相对标准偏差（RSD）为 4.3%至 10%。结果表明，仅在豆类或朝鲜蓟瓶的液相中测定添加剂并不适合了解其总量，因为添加剂分布在液相和固相之间。通过“自下而上”的方法评估了分析方法的每个步骤对测量浓度的不确定度的贡献，包括样品的不均匀性，在研究了二十个样品后，发现其非常多变。
