SIMULTANEOUS DETERMINATION OF QUINOLINE YELLOW AND TARTRAZINE BY DERIVATIVE SPECTROMETRY AND RATIO SPECTRA DERIVATIVE

Two methods for determining quinoline yellow (E-104) and tartrazine (E-102) in their mixtures by first derivative spectrometry and by first derivative of the ratio spectra are described. The procedures do not require any separation step. By the first method, the measurements are obtained in the zero-crossing wavelengths. The determinations of quinoline yellow and tartrazine are also done by the first derivative of the ratio spectra. The calibration graphs are linear up to 17.6 mug/ml for both compounds and by both methods. The methods are applied for determining both compounds in four commercial food products.