Critical review of analytical and bioanalytical verification of the authenticity of coffee

Abstract

Background: The driving factors for the commercial adulteration of coffee are reviewed. Objective: Methods have been assessed for the identification of the most common materials used to adulterate coffee by dilution, to establish the geographic origins, the genotypes of beans, and to assess the authenticity of Kopi Luwak coffee. Method: The literature was surveyed manually and electronically from 1820 to 2018. Results: A flow diagram has been developed to summarize the best approaches to deal with the authentication of coffee. Conclusions: Encouragement is given to the interlaboratory validation of spectroscopic approaches, the exploration of civet cat deoxyribonucleic acid for the identification of Kopi Luwak, and the development of appropriately large and well-curated datasets of authenticity information across multiple techniques. Highlights: The current analytical difficulties in the authentication of coffee are highlighted and suggestions made to improve the situation.