Application of chemometrics based on digital image analysis for simultaneous determination of tartrazine and sunset yellow in food samples

Azo dyes, such as tartrazine and sunset yellow, are widely used as affordable and stable food colorants. Accurate quantification is crucial in foods for regulatory monitoring to ensure compliance with safety standards and minimize health risks. This study developed a low-cost and eco-friendly method using digital images and chemometrics for the simultaneous determination of these dyes in food samples. The best prediction results were achieved by applying partial least squares regression to RGB + Grayscale+HSI color histograms, with R² of 0.9977, 0.9989, RMSEP of 0.21, 0.10 mg/L and REP of 1.6, 1.0 % for tartrazine and sunset yellow, respectively. The method was successfully applied for determination of tartrazine and sunset yellow in soft drink samples, producing results comparable to those obtained from the HPLC method. This innovative approach provides a practical and reliable alternative for monitoring the dye concentrations, supporting both food manufacturers and health authorities in ensuring compliance with safety standards.