SIMULTANEOUS DETERMINATION OF QUINOLINE YELLOW AND SUNSET YELLOW BY DERIVATIVE SPECTROPHOTOMETRY AND RATIO SPECTRA DERIVATIVE

Three methods for determining Quinoline Yellow (E-104) and Sunset Yell ow (E-110) in mixtures by first and second derivative spectrophotometr y and by first derivative of the ratio spectra are described. The proc edures do not require any separation step. By the first and second met hods, the measurements are obtained in the zero-crossing wavelengths a nd the calibration graphs are linear up to 24 mug/mL of Quinoline Yell ow and 40 mug/mL of Sunset Yellow. The determination of Quinoline Yell ow is also done by the first derivative of the ratio spectra. The meth ods are applied for determining both compounds in four food commercial products.