Application of nuclear magnetic resonance spectroscopy in food adulteration determination: the example of Sudan dye I in paprika powder

• Published in: Scientific reports 2017-06, Vol.7 (1), p.2637-9, Article 2637
• Main Authors: Hu, Yaxi, Wang, Shuo, Wang, Shenlin, Lu, Xiaonan
• Format: Article
• Language: English
• Subjects: 140/131; 639/638/11/878; 639/638/440/94; Acetonitrile; Capsicum - chemistry; Carcinogens - analysis; Carcinogens - chemistry; Coloring Agents - analysis; Food Contamination; Humanities and Social Sciences; Magnetic Resonance Spectroscopy; multidisciplinary; Naphthols - analysis; Naphthols - chemistry; NMR; Nuclear magnetic resonance; Powder; Regression analysis; Science; Science (multidisciplinary); Spectrometers; Spectroscopy; Spices
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-017-02921-8

Carcinogenic Sudan I has been added illegally into spices for an apparent freshness. 1 H solution and solid-state (SS) nuclear magnetic resonance (NMR) spectroscopies were applied and compared for determination of Sudan I in paprika powders (PPs). For solution NMR, PPs spiked with Sudan I were extracted with acetonitrile, centrifuged, rotor-evaporated, and re-dissolved in DMSO-d6 for spectral collection. For SSNMR, Sudan I contaminated PPs were mixed with DMSO-d6 solution and used for spectral collection. Linear regression models constructed for quantitative analyses resulted in the average accuracies for unknown samples as 98% and 105%, respectively. Limits of detection for the solution NMR and SSNMR spectrometers were 6.7 and 128.6 mg kg −1 , while the limits of quantification were 22.5 and 313.7 mg kg −1 . The overall analysis time required by both methods was similar (35 and 32 min). Both NMR techniques are feasible for rapid and accurate determination of Sudan I adulteration in PPs.