Mass Spectrometry Laboratory, MolSys Research Unit, University of Liege, Allée de la Chimie 3, B-6c Sart-Tilman, B-4000 Liege, Belgium.
J AOAC Int. 2021 May 21;104(2):253-259. doi: 10.1093/jaoacint/qsaa102.
Furan and its alkyl substituted (2-methylfuran, 3-methylfuran, 2,3-dimethylfuran, 2,5-dimethylfuran) are found in a range between ppm to sub-ppb levels in many foodstuffs undergoing heat treatments like coffee, chicory, or even chocolate.
Two major objectives are presented. First, we aim at optimizing and validating a HS-SPME-GC-MS method for the quantification of five alkylfurans in chocolate. Second, we focus our study on measuring the quantitative impact of engraving technique on the formation of furan and its derivatives in chocolate, from the raw callets to processed end-products.
HS-SPME-GC-MS method operating in SIM mode and using isotope dilution technique with deuterated homologue internal standards was used to quantify alkylfurans in chocolate.
Good repeatability (RSD% = 0.1-8%, in duplicate) and intermediate precision (RSD% = 1.7-7%, n = 6) were obtained for these five process contaminants at 10, 25, and 50 µg/kg. Trueness was varying between 81 and 109%. LoQ ranged from 0.48 to 2.50 µg/kg. Relative expanded measurement uncertainties ranged from 6 to 30%. Finally, tempering is responsible for a 24% increase in furan contamination, while the laser engraving technique results in an additional 31% increase in furan. A similar trend was also observed for 2-methylfuran and 3-methylfuran, whereas no significant increases were observed for 2,3-dimethylfuran and 2,5-dimethylfuran.
A reliable and sensitive method of HS-SPME-GC-MS was reported for the first time for the analysis of furan and four alkylfurans in chocolate. This paper demonstrated that engraving using laser-based techniques can increase the levels of these compounds by up to 30%.
呋喃及其烷基取代物（2-甲基呋喃、3-甲基呋喃、2,3-二甲基呋喃、2,5-二甲基呋喃）在经过热加工的多种食品中以 ppm 至亚 ppb 水平存在，如咖啡、菊苣，甚至巧克力。
本研究提出了两个主要目标。首先，我们旨在优化和验证 HS-SPME-GC-MS 方法，用于定量分析巧克力中的五种烷基呋喃。其次，我们专注于研究刻蚀技术对巧克力中呋喃及其衍生物形成的定量影响，从原料巧克力到加工后的成品。
采用 HS-SPME-GC-MS 方法，在 SIM 模式下操作，并使用氘代同系物内标进行同位素稀释技术，定量分析巧克力中的烷基呋喃。
在 10、25 和 50μg/kg 时，这五种工艺污染物的重复性（RSD%=0.1-8%，重复两次）和中间精密度（RSD%=1.7-7%，n=6）良好。准确度在 81%至 109%之间变化。LOQ 范围为 0.48 至 2.50μg/kg。相对扩展测量不确定度范围为 6%至 30%。最后，调温使呋喃污染增加 24%，而激光刻蚀技术使呋喃增加 31%。对于 2-甲基呋喃和 3-甲基呋喃也观察到类似的趋势，而 2,3-二甲基呋喃和 2,5-二甲基呋喃则没有明显增加。
本文首次报道了一种可靠、灵敏的 HS-SPME-GC-MS 方法，用于分析巧克力中的呋喃和四种烷基呋喃。本文表明，使用基于激光的技术进行刻蚀可以将这些化合物的水平提高多达 30%。
