Analytical advances for detecting illicit dyes in foods: Spectroscopy, chromatography, mass spectrometry, and...

Although certified food dyes are strictly regulated by the United States Food and Drug Administration (FDA) and the European Commission (EC) and are considered safe at permitted levels, the fraudulent use of unauthorized dyes or contamination of approved colorants with harmful substances continues to pose risks to public health. Although trace amounts of colorants are typically used in food products, minimal adulteration might compromise safety, highlighting the need for highly sensitive detection methods. This review provides a critical and comprehensive overview of recent advances in analytical strategies for detecting dye adulteration in food. Conventional approaches, including spectrophotometry, chromatography, and mass spectrometry, are highlighted for their precision and sensitivity, while emerging techniques such as electrochemical sensors and smartphone-based colorimetric assays are recognized for their portability, cost-effectiveness, and potential for on-site applications. Regional case studies are also discussed to illustrate the real-world impact of dye adulteration and the ongoing challenges in regulatory enforcement. By emphasizing both established and innovative approaches, this review underscores the importance of scalable, eco-friendly technologies capable of detecting trace levels of adulteration. Ultimately, it calls for global harmonization of food safety regulations to strengthen consumer protection and enhance food quality standards worldwide.