Coffee Adulteration: More than Two Decades of Research

Abstract

Coffee is a ubiquitous food product of considerable economic importance to the countries that produce and export it. The adulteration of roasted coffee is a strategy used to reduce costs. Conventional methods employed to identify adulteration in roasted and ground coffee involve optical and electron microscopy, which require pretreatment of samples and are time-consuming and subjective. Other analytical techniques have been studied that might be more reliable, reproducible, and widely applicable. The present review provides an overview of three analytical approaches (physical, chemical, and biological) to the identification of coffee adulteration. A total of 30 published articles are considered. It is concluded that despite the existence of a number of excellent studies in this area, there still remains a lack of a suitably sensitive and widely applicable methodology able to take into account the various different aspects of adulteration, considering coffee varieties, defective beans, and external agents.

Authentication of the Origin, Variety and Roasting Degree of Coffee Samples by Non-Targeted HPLC-UV Fingerprinting and Chemometrics. Application to the Detection and Quantitation of Adulterated Coffee Samples

“…[13][14][15][16][17] to coffee blends to obtain an economical profit by making the final product less expensive. An interesting review addressing more than two decades of coffee adulteration was published by Toci et al [18], revealing the need to control the authenticity and origin of coffee samples to prevent such bad practices. One of the most common coffee adulteration practices is that of Arabica with Robusta varieties blend [18][19][20][21].…”

Comparative evaluation of flavor compounds in fermented green and roasted coffee beans by solid phase microextraction‐gas chromatography/mass spectrometry

“…Coffee is one of the most traded agricultural products and consumed beverages in the world . Two major types of coffee with approximately 100 varieties, Coffea arabica L. (Arabica) and Coffea canephora Pierre ex A.Froehner (Robusta), represent approximately 70% and 30% of the global coffee market, respectively .…”

Modern analytical methods for the detection of food fraud and adulteration by food category

“…The adulteration of roasted coffee is both frequent and diversified. It can involve the quality of the beans (species, geographical origin and defective beans), as well as the addition of other substances (coffee husks and stems, maize, barley, chicory, wheat middlings, brown sugar, soybean, rye and triticale) to coffee blends with the aim of making them less expensive …”

“…well as the addition of other substances (coffee husks and stems, maize, barley, chicory, wheat middlings, brown sugar, soybean, rye and triticale) to coffee blends with the aim of making them less expensive. 109,110 The world's commercial coffee comes from only two species: Coffea arabica (arabica coffee) and Coffea canephora (robusta coffee). Arabica coffee is the most appreciated by consumers because of its intense aroma, low bitterness and low caffeine content.…”