Low-level detections of Sudan I, II, III and IV in spices and Chili-containing foodstuffs using UPLC-ESI-MS/MS.

Sudan dyes are red, synthetic azo dyes that are not allowed in foodstuffs in the European Union (Council Directive 94/36/EC). However, subppm levels of Sudan dye in spices are regularly reported, and it is assumed that these appearances are due to cross-contamination. In this paper, we present a newly developed fast and sensitive method for the quantification of Sudan I, II, III, and IV, using liquid-liquid extraction and UPLC-MS/MS analysis, and giving quantification limits ranging from 2.