An HPLC method developed for chromatographic separation of food colorants enables the separation and quantitative determination of 14 colorants within 50 min.The method provides stable retention times, and detection limits ranging from 0.01 to 1.23 ng. The 14 colorants furnished
18 peaks because E 104 gave four peaks (two monosulfonated and two bissulfonated
forms of quinoline yellow) and E 142 gave two peaks. For determination of the colorants DAD was employed at the wavelengths 430 nm (yellow colorants), 486 nm (E 110), 520 nm (red colorants),
and 608 nm (blue, black and green colorants). Thus, for an unambiguous identification of the colorants the retention times and the absorption spectra can be compared with those of standards, thus enabling reliable colorant analysis.