TRACING THE TRUE COFFEE BEANS: A CLOSER LOOK AT ADULTERATION AND AUTHENTICATION

Abstract

Coffee is among the most widely consumed beverages worldwide and represents a high-value commodity with a complex global supply chain, making it particularly vulnerable to adulteration and other forms of food fraud. This review summarizes the historical background of coffee adulteration and critically discusses the major authenticity challenges associated with species substitution, geographical origin mislabeling, and the addition of low-cost adulterants such as cereals, chicory, husks, silverskin, spent coffee grounds, and legumes. Emphasis is placed on the evolution of authentication strategies, from traditional chemical and microscopic approaches to modern analytical techniques, including chromatography, spectroscopy, DNA-based tools, and emerging omics platforms. Attention is given to metabolomics, volatomics, proteomics, and fingerprinting approaches coupled with chemometric and machine learning tools, which have significantly improved the detection of adulteration and the verification of coffee origin and species identity. Despite substantial progress, important limitations remain, including matrix complexity, the effects of roasting and processing, limited availability of representative reference materials, and insufficient harmonization of food fraud reporting. Overall, the review highlights the need for integrated, rapid, reliable, and cost-effective authentication systems to strengthen regulatory control, protect consumers, and preserve trust and transparency in the global coffee market.